From: Xiao Jin <jin.xiao@samsung.com>
Date: Thu, 25 Oct 2018 07:14:00 +0000 (+0800)
Subject: fix bug of loop device num is not alwasy 0
X-Git-Tag: submit/devel/20190730.074558~5
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d70562693b3105cbb619e29bfa34bcba488b9129;p=tools%2Fitest-cases-mic.git

fix bug of loop device num is not alwasy 0

Change-Id: If9c634af04f889cfc0744d47948c17d52b7e95be
---

diff --git a/cases/create/func_cases/mic_cr_auto_fs.case b/cases/create/func_cases/mic_cr_auto_fs.case
old mode 100644
new mode 100755
index 6d6a413..6e74f4d
--- a/cases/create/func_cases/mic_cr_auto_fs.case
+++ b/cases/create/func_cases/mic_cr_auto_fs.case
@@ -22,11 +22,15 @@ assert img_file in manifest['fs']['image_files']
     <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto handset_blackbay_fs.ks --logfile=log.file
 grep "Finished" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 fs_dir=$(ls mic-output/ | grep 'handset_blackbay_fs-.*-rs.tar.gz')
 mic_version=$(mic --version  2>&1 | awk -F ' ' '{print $2}')
 python parse_manifest.py $fs_dir $mic_version
diff --git a/cases/create/func_cases/mic_cr_auto_fs_d_v_i.case b/cases/create/func_cases/mic_cr_auto_fs_d_v_i.case
old mode 100644
new mode 100755
index f251626..746f75a
--- a/cases/create/func_cases/mic_cr_auto_fs_d_v_i.case
+++ b/cases/create/func_cases/mic_cr_auto_fs_d_v_i.case
@@ -22,11 +22,15 @@ assert img_file in manifest['fs']['image_files']
     <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic cr auto handset_blackbay_fs_d_v_i.ks --logfile=log.file
 grep "Finished" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 fs_dir=$(ls mic-output/ | grep 'handset_blackbay_fs_d_v_i-.*-rs.tar.gz')
 mic_version=$(mic --version | awk '{print $2}')
 python parse_manifest.py $fs_dir $mic_version
diff --git a/cases/create/func_cases/mic_cr_auto_fs_parameter_run_script.case b/cases/create/func_cases/mic_cr_auto_fs_parameter_run_script.case
old mode 100644
new mode 100755
index c71f248..2335482
--- a/cases/create/func_cases/mic_cr_auto_fs_parameter_run_script.case
+++ b/cases/create/func_cases/mic_cr_auto_fs_parameter_run_script.case
@@ -20,12 +20,16 @@ assert img_file in manifest['fs']['image_files']
     <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto handset_blackbay_fs.ks --logfile=log.file --run_script="cd ./mic-output; cp manifest.json run_script.json"
 grep "Finished" log.file
 test -f ./mic-output/run_script.json
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 fs_dir=$(ls mic-output/ | grep 'handset_blackbay_fs-.*-rs.tar.gz')
 mic_version=$(mic --version  2>&1 | awk -F ' ' '{print $2}')
 python parse_manifest.py $fs_dir $mic_version
diff --git a/cases/create/func_cases/mic_cr_auto_loop.case b/cases/create/func_cases/mic_cr_auto_loop.case
old mode 100644
new mode 100755
index d71ad46..3a69ef8
--- a/cases/create/func_cases/mic_cr_auto_loop.case
+++ b/cases/create/func_cases/mic_cr_auto_loop.case
@@ -10,11 +10,15 @@ which called magic line, and magic line in this ks file is:
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto handset_blackbay.ks --logfile=log.file
 grep "Finished" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ls mic-output/ | grep 'handset_blackbay-.*-rs.zip'
 ]]></steps>
   <teardown><![CDATA[
diff --git a/cases/create/func_cases/mic_cr_auto_loop_cp_tpk_error.case b/cases/create/func_cases/mic_cr_auto_loop_cp_tpk_error.case
old mode 100644
new mode 100755
index 0fcee0b..ea3e32e
--- a/cases/create/func_cases/mic_cr_auto_loop_cp_tpk_error.case
+++ b/cases/create/func_cases/mic_cr_auto_loop_cp_tpk_error.case
@@ -7,11 +7,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 (! sudo mic -d -v cr auto handset_blackbay.ks --logfile=log.file --tpk_install="./")
 grep "Not all files in the path" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/func_cases/mic_cr_auto_loop_http_tpk.case b/cases/create/func_cases/mic_cr_auto_loop_http_tpk.case
old mode 100644
new mode 100755
index 2c3c911..0c5bda3
--- a/cases/create/func_cases/mic_cr_auto_loop_http_tpk.case
+++ b/cases/create/func_cases/mic_cr_auto_loop_http_tpk.case
@@ -9,11 +9,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto handset_blackbay_http_tpk_repo.ks --logfile=log.file --tpk_install="./tpk"
 grep "Finished" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo mkdir -p mic-output/platform
 sudo mount mic-output/platform.img mic-output/platform
 sudo test -f mic-output/platform/usr/apps/.preload-tpk/org.tizen.calendar-1.0.0-x86.tpk
diff --git a/cases/create/func_cases/mic_cr_auto_loop_multi_mic_run.case b/cases/create/func_cases/mic_cr_auto_loop_multi_mic_run.case
old mode 100644
new mode 100755
index 9e7d9ee..5ac0b4d
--- a/cases/create/func_cases/mic_cr_auto_loop_multi_mic_run.case
+++ b/cases/create/func_cases/mic_cr_auto_loop_multi_mic_run.case
@@ -7,13 +7,17 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto handset_blackbay.ks --logfile=log1.file
 sudo mic -d -v cr auto handset_blackbay.ks --logfile=log2.file --cachedir=/var/tmp/mic/cache2 -o my-mic-output
 grep "Finished" log1.file
 grep "Finished" log2.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ls mic-output/ | grep 'handset_blackbay-.*-rs.zip'
 ls my-mic-output/ | grep 'handset_blackbay-.*-rs.zip'
 ]]></steps>
diff --git a/cases/create/func_cases/mic_cr_auto_loop_package_constPtr.case b/cases/create/func_cases/mic_cr_auto_loop_package_constPtr.case
old mode 100644
new mode 100755
index 6a6610e..0afa3ae
--- a/cases/create/func_cases/mic_cr_auto_loop_package_constPtr.case
+++ b/cases/create/func_cases/mic_cr_auto_loop_package_constPtr.case
@@ -7,11 +7,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto handset_blackbay_package_constPtr.ks --logfile=log.file
 grep "Finished" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ls mic-output/ | grep 'handset_blackbay_.*-rs.zip'
 ]]></steps>
   <teardown><![CDATA[
diff --git a/cases/create/func_cases/mic_cr_auto_loop_partition_expand.case b/cases/create/func_cases/mic_cr_auto_loop_partition_expand.case
old mode 100644
new mode 100755
index 99a52a7..6f0f5eb
--- a/cases/create/func_cases/mic_cr_auto_loop_partition_expand.case
+++ b/cases/create/func_cases/mic_cr_auto_loop_partition_expand.case
@@ -7,12 +7,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto handset_blackbay_partition_expand.ks --logfile=log.file
 grep "Initial partition size expanded" log.file
 grep "Finished" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/func_cases/mic_cr_auto_loop_rpm_debug.case b/cases/create/func_cases/mic_cr_auto_loop_rpm_debug.case
old mode 100644
new mode 100755
index d671642..9b9c4d0
--- a/cases/create/func_cases/mic_cr_auto_loop_rpm_debug.case
+++ b/cases/create/func_cases/mic_cr_auto_loop_rpm_debug.case
@@ -7,11 +7,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto handset_blackbay.ks --logfile=log.file --rpm-debug
 grep "Finished" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ls mic-output/ | grep 'handset_blackbay-.*-rs.zip'
 ]]></steps>
   <teardown><![CDATA[
diff --git a/cases/create/func_cases/mic_cr_auto_raw.case b/cases/create/func_cases/mic_cr_auto_raw.case
index 06626b8..b5d158a 100755
--- a/cases/create/func_cases/mic_cr_auto_raw.case
+++ b/cases/create/func_cases/mic_cr_auto_raw.case
@@ -26,11 +26,15 @@ assert manifest['raw']['sdb']['image'] == img_file
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto ivi.ks --logfile=log.file
 grep "Finished" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ls mic-output/ | grep 'ivi-.*-sdb.bmap'
 ls mic-output/ | grep 'ivi-.*-sdb.raw.bz2'
 ls mic-output/ | grep 'ivi-.*-vmlinuz-*'
diff --git a/cases/create/func_cases/mic_cr_auto_raw_gpt.case b/cases/create/func_cases/mic_cr_auto_raw_gpt.case
index b02800d..9bf6ad8 100755
--- a/cases/create/func_cases/mic_cr_auto_raw_gpt.case
+++ b/cases/create/func_cases/mic_cr_auto_raw_gpt.case
@@ -6,11 +6,15 @@
     <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto ivi_with_installerfw.ks --logfile=log.file
 grep "Finished" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ls mic-output/ | grep 'ivi_with_installerfw-.*-sdb.bmap'
 ls mic-output/ | grep 'ivi_with_installerfw-.*-sdb.raw.bz2'
 ls mic-output/ | grep 'ivi_with_installerfw-.*-vmlinuz-*'
diff --git a/cases/create/func_cases/mic_cr_fs_inc-src_cache-dir_arch_logfile_armv7l.case b/cases/create/func_cases/mic_cr_fs_inc-src_cache-dir_arch_logfile_armv7l.case
old mode 100644
new mode 100755
index 49bb63a..5acfc60
--- a/cases/create/func_cases/mic_cr_fs_inc-src_cache-dir_arch_logfile_armv7l.case
+++ b/cases/create/func_cases/mic_cr_fs_inc-src_cache-dir_arch_logfile_armv7l.case
@@ -8,7 +8,7 @@
         <![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 enforce_path=$(sudo which setenforce || true)
 if [ ! -z $enforce_path ];then
     sudo $enforce_path 0 || true
@@ -18,7 +18,11 @@ test -d ./my_output
 test -f fs_src.log
 grep "Finished" fs_src.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 test -d fs_cache
 ls ./my_output | grep 'armv7l*'
 ls fs_cache/packages/Tizen-base | grep rpm
diff --git a/cases/create/func_cases/mic_cr_fs_inc-src_cp-knl_cache-dir_ia32.case b/cases/create/func_cases/mic_cr_fs_inc-src_cp-knl_cache-dir_ia32.case
old mode 100644
new mode 100755
index c3ec6a7..30b8345
--- a/cases/create/func_cases/mic_cr_fs_inc-src_cp-knl_cache-dir_ia32.case
+++ b/cases/create/func_cases/mic_cr_fs_inc-src_cp-knl_cache-dir_ia32.case
@@ -10,11 +10,15 @@
         <![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr fs handset_blackbay.ks --include-src --copy-kernel --cachedir=./mic-cache  --logfile=log.file
 grep "Finished" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ls -l ./mic-output | grep 'handset_blackbay.*-vmlinuz-*'
 test -d mic-cache/
 ls -l mic-cache/packages/Tizen-base | grep rpm
diff --git a/cases/create/func_cases/mic_cr_fs_install-pkgs_ia32.case b/cases/create/func_cases/mic_cr_fs_install-pkgs_ia32.case
old mode 100644
new mode 100755
index 8276b43..884b8eb
--- a/cases/create/func_cases/mic_cr_fs_install-pkgs_ia32.case
+++ b/cases/create/func_cases/mic_cr_fs_install-pkgs_ia32.case
@@ -7,11 +7,15 @@
     <![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr fs ivi-2.0-alpha-debuginfo.ks --install-pkgs=debuginfo  --logfile=mic1.log
 grep 'Finished' mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 image_name=`ls ./mic-output | grep 'ivi-2.0-alpha-debuginfo'`
 test -d ./mic-output/$image_name
 sudo chroot ./mic-output/$image_name rpm -qa | grep 'debuginfo'
diff --git a/cases/create/func_cases/mic_cr_loop_check-pkgs_tmpfs_ia32.case b/cases/create/func_cases/mic_cr_loop_check-pkgs_tmpfs_ia32.case
old mode 100644
new mode 100755
index b770d74..50fa4ac
--- a/cases/create/func_cases/mic_cr_loop_check-pkgs_tmpfs_ia32.case
+++ b/cases/create/func_cases/mic_cr_loop_check-pkgs_tmpfs_ia32.case
@@ -6,7 +6,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --tmpfs --check-pkgs=bash,rpm --logfile=handset1.log
 
 test -f handset1.log
@@ -14,13 +14,21 @@ test -f handset1.log
 grep 'Finished' handset1.log
 
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 test -f ./mic-output/platform.img
 
 sudo mic -d -v cr loop handset_blackbay.ks --check-pkgs=bashrr --logfile=handset2.log 2>&1 | tee handset2.log || true
 grep "Packages absent in image: bashrr" handset2.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/func_cases/mic_cr_loop_compress_local-pkgs_record-pkgs_pack-to_armv7l.case b/cases/create/func_cases/mic_cr_loop_compress_local-pkgs_record-pkgs_pack-to_armv7l.case
old mode 100644
new mode 100755
index 9ee8651..ba8ebba
--- a/cases/create/func_cases/mic_cr_loop_compress_local-pkgs_record-pkgs_pack-to_armv7l.case
+++ b/cases/create/func_cases/mic_cr_loop_compress_local-pkgs_record-pkgs_pack-to_armv7l.case
@@ -8,7 +8,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 enforce_path=$(sudo which setenforce || true)
 if [ ! -z $enforce_path ];then
     sudo $enforce_path 0 || true
@@ -23,7 +23,11 @@ sudo mic -d -v cr loop armv7l.ks \
 grep "Finished" log.file
 
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 grep 'Marking .*.rpm to be installed' log.file
 
 test -f ./mic-output/armv7l*.tar
diff --git a/cases/create/func_cases/mic_cr_loop_config_cmpress_runtime_ia32.case b/cases/create/func_cases/mic_cr_loop_config_cmpress_runtime_ia32.case
old mode 100644
new mode 100755
index b0d6cc5..1f8deb5
--- a/cases/create/func_cases/mic_cr_loop_config_cmpress_runtime_ia32.case
+++ b/cases/create/func_cases/mic_cr_loop_config_cmpress_runtime_ia32.case
@@ -10,7 +10,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks \
   --config=mic.conf \
   --compress-image=bz2 \
@@ -18,7 +18,11 @@ sudo mic -d -v cr loop handset_blackbay.ks \
   --logfile=mic1.log
 grep -i "Finished" mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 grep 'Start mic in bootstrap' mic1.log
 sudo rm mic1.log
 sudo test -d ./my_mic-output
@@ -26,7 +30,11 @@ sudo test -e ./my_mic-output/platform.img.bz2
 sudo mic -d -v cr loop handset_blackbay.ks --outdir=out2  --logfile=mic2.log
 grep "Finished" mic2.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo rm mic2.log
 sudo test -f ./out2/platform.img
 
diff --git a/cases/create/func_cases/mic_cr_loop_cpio.case b/cases/create/func_cases/mic_cr_loop_cpio.case
old mode 100644
new mode 100755
index 6fcd652..0a37cc2
--- a/cases/create/func_cases/mic_cr_loop_cpio.case
+++ b/cases/create/func_cases/mic_cr_loop_cpio.case
@@ -1,27 +1,25 @@
-<testcase>
-  <summary>create loop image by cpio</summary>
-  <fixtures>
-    <copy src="ks_files/armv7l_cpio.ks" />
-  </fixtures>
-  <steps><![CDATA[
-losetup_path=$(sudo which losetup)
-sudo $losetup_path -a
-#sudo $losetup_path -a | wc -l | xargs test 0 -eq
-loop_used_before=$(sudo $losetup_path -a | wc -l)
-sudo mic -d -v cr loop armv7l_cpio.ks -o out1 --logfile=mic1.log
-grep -i 'Finished' mic1.log
-sudo $losetup_path -a
-#sudo $losetup_path -a | wc -l | xargs test 0 -eq
-loop_used_after=$(sudo $losetup_path -a | wc -l)
-if("$loop_used_before"!="$loop_used_after");then
-    echo "Number of loop devices is not the same with previous number."
-    exit 1
-fi
-test -f ./out1/boot.img
-]]></steps>
-  <teardown><![CDATA[
-echo "cleaning..."
-sudo rm -rf ./out1/
-sudo rm mic1.log
-]]></teardown>
-</testcase>
+<testcase>
+  <summary>create loop image by cpio</summary>
+  <fixtures>
+    <copy src="ks_files/armv7l_cpio.ks" />
+  </fixtures>
+  <steps><![CDATA[
+losetup_path=$(sudo which losetup)
+sudo $losetup_path -a
+loop_used_before=$(sudo $losetup_path -a | wc -l)
+sudo mic -d -v cr loop armv7l_cpio.ks -o out1 --logfile=mic1.log
+grep -i 'Finished' mic1.log
+sudo $losetup_path -a
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
+test -f ./out1/boot.img
+]]></steps>
+  <teardown><![CDATA[
+echo "cleaning..."
+sudo rm -rf ./out1/
+sudo rm mic1.log
+]]></teardown>
+</testcase>
diff --git a/cases/create/func_cases/mic_cr_loop_logfile_conf_shrink_release_pkgmgr_armv7l.case b/cases/create/func_cases/mic_cr_loop_logfile_conf_shrink_release_pkgmgr_armv7l.case
old mode 100644
new mode 100755
index 33f637d..1382338
--- a/cases/create/func_cases/mic_cr_loop_logfile_conf_shrink_release_pkgmgr_armv7l.case
+++ b/cases/create/func_cases/mic_cr_loop_logfile_conf_shrink_release_pkgmgr_armv7l.case
@@ -8,7 +8,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 # on some platforms, the command "setenforce 0" is needed to be executed,
 # on some other platforms, it's not needed to execute this command or 
 # no related package is installed, so we added "||"
@@ -23,7 +23,11 @@ sudo test -f /custome/arm.log
 grep "Finished" /custome/arm.log
 
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 test -f my_mic-output/tizen-2.2_20130719.3/images/armv7l/MD5SUMS
 test -f my_mic-output/tizen-2.2_20130719.3/images/armv7l/boot.img
 test -f my_mic-output/tizen-2.2_20130719.3/images/armv7l/platform.img
diff --git a/cases/create/func_cases/mic_cr_loop_run_script.case b/cases/create/func_cases/mic_cr_loop_run_script.case
old mode 100644
new mode 100755
index 8fea351..e8ec820
--- a/cases/create/func_cases/mic_cr_loop_run_script.case
+++ b/cases/create/func_cases/mic_cr_loop_run_script.case
@@ -1,27 +1,25 @@
-<testcase>
-  <summary>Run certain script before creation of tar.gz image</summary>
-  <fixtures>
-    <copy src="ks_files/handset_blackbay_runscript.ks" />
-  </fixtures>
-  <steps><![CDATA[
-losetup_path=$(sudo which losetup)
-sudo $losetup_path -a
-#sudo $losetup_path -a | wc -l | xargs test 0 -eq
-loop_used_before=$(sudo $losetup_path -a | wc -l)
-sudo mic -d -v cr loop handset_blackbay_runscript.ks -o out1 --logfile=mic1.log
-grep -i 'Finished' mic1.log
-sudo $losetup_path -a
-#sudo $losetup_path -a | wc -l | xargs test 0 -eq
-loop_used_after=$(sudo $losetup_path -a | wc -l)
-if("$loop_used_before"!="$loop_used_after");then
-    echo "Number of loop devices is not the same with previous number."
-    exit 1
-fi
-test -f ./out1/platform.sgn
-]]></steps>
-  <teardown><![CDATA[
-echo "cleaning..."
-sudo rm -rf ./out1/
-sudo rm mic1.log
-]]></teardown>
-</testcase>
+<testcase>
+  <summary>Run certain script before creation of tar.gz image</summary>
+  <fixtures>
+    <copy src="ks_files/handset_blackbay_runscript.ks" />
+  </fixtures>
+  <steps><![CDATA[
+losetup_path=$(sudo which losetup)
+sudo $losetup_path -a
+loop_used_before=$(sudo $losetup_path -a | wc -l)
+sudo mic -d -v cr loop handset_blackbay_runscript.ks -o out1 --logfile=mic1.log
+grep -i 'Finished' mic1.log
+sudo $losetup_path -a
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
+test -f ./out1/platform.sgn
+]]></steps>
+  <teardown><![CDATA[
+echo "cleaning..."
+sudo rm -rf ./out1/
+sudo rm mic1.log
+]]></teardown>
+</testcase>
diff --git a/cases/create/func_cases/mic_cr_loop_shrink_outdir_logfile_pkgmgr_ia32.case b/cases/create/func_cases/mic_cr_loop_shrink_outdir_logfile_pkgmgr_ia32.case
old mode 100644
new mode 100755
index 2e0c924..624ccdf
--- a/cases/create/func_cases/mic_cr_loop_shrink_outdir_logfile_pkgmgr_ia32.case
+++ b/cases/create/func_cases/mic_cr_loop_shrink_outdir_logfile_pkgmgr_ia32.case
@@ -7,13 +7,17 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks -o out1 --pkgmgr=zypp  --logfile=mic1.log
 
 grep 'Finished' mic1.log
 
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 test -f ./out1/platform.img
 
 sudo mic -d -v cr loop handset_blackbay.ks -o out2 --shrink  --logfile=mic2.log
@@ -21,7 +25,11 @@ sudo mic -d -v cr loop handset_blackbay.ks -o out2 --shrink  --logfile=mic2.log
 grep 'Finished' mic2.log
 
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 test -f ./out2/platform.img
 
 source compute_volume.sh
diff --git a/cases/create/func_cases/mic_cr_qcow_check-pkgs_tmpfs_ia32.case b/cases/create/func_cases/mic_cr_qcow_check-pkgs_tmpfs_ia32.case
old mode 100644
new mode 100755
index 4c79320..cc11876
--- a/cases/create/func_cases/mic_cr_qcow_check-pkgs_tmpfs_ia32.case
+++ b/cases/create/func_cases/mic_cr_qcow_check-pkgs_tmpfs_ia32.case
@@ -9,7 +9,7 @@ losetup_path=$(sudo which losetup)
 
 sudo $losetup_path -a
 
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 
 sudo mic -d -v cr qcow qcow_image.ks --tmpfs --check-pkgs=bash,rpm --logfile=qcow1.log -k /home/build/mic-tmp-cache
 
@@ -23,7 +23,11 @@ grep 'Finished' qcow1.log
 
 sudo $losetup_path -a
 
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 
 test -f ./mic-output/emulimg-3.0.img
 
@@ -35,7 +39,11 @@ grep "Packages absent in image: bashrr" qcow2.log
 
 sudo $losetup_path -a
 
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 
 ]]></steps>
   <teardown><![CDATA[
diff --git a/cases/create/func_cases/mic_cr_qcow_config_runtime_ia32.case b/cases/create/func_cases/mic_cr_qcow_config_runtime_ia32.case
old mode 100644
new mode 100755
index 0ea2426..953101b
--- a/cases/create/func_cases/mic_cr_qcow_config_runtime_ia32.case
+++ b/cases/create/func_cases/mic_cr_qcow_config_runtime_ia32.case
@@ -12,7 +12,7 @@ losetup_path=$(sudo which losetup)
 
 sudo $losetup_path -a
 
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 
 # set tmpdir and roordir to /home/build to avoid space lacking during build
 sed -i 's!^\(tmpdir=\).*!\1 /home/build/mic/tmp!g' mic.conf
@@ -32,7 +32,11 @@ grep -i "Finished" mic.log
 
 sudo $losetup_path -a
 
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 
 grep 'Start mic in bootstrap' mic.log
 
diff --git a/cases/create/func_cases/mic_cr_qcow_local-pkgs_record-pkgs.case b/cases/create/func_cases/mic_cr_qcow_local-pkgs_record-pkgs.case
old mode 100644
new mode 100755
index 796cde1..01b078d
--- a/cases/create/func_cases/mic_cr_qcow_local-pkgs_record-pkgs.case
+++ b/cases/create/func_cases/mic_cr_qcow_local-pkgs_record-pkgs.case
@@ -11,7 +11,7 @@ losetup_path=$(sudo which losetup)
 
 sudo $losetup_path -a
 
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 
 enforce_path=$(sudo which setenforce || true)
 
@@ -34,7 +34,11 @@ grep "Finished" log.file
 
 sudo $losetup_path -a
 
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 
 grep 'Marking .*.rpm to be installed' log.file
 
diff --git a/cases/create/func_cases/mic_cr_qcow_logfile_conf_release_pkgmgr.case b/cases/create/func_cases/mic_cr_qcow_logfile_conf_release_pkgmgr.case
old mode 100644
new mode 100755
index 77fb4b7..36ca9cc
--- a/cases/create/func_cases/mic_cr_qcow_logfile_conf_release_pkgmgr.case
+++ b/cases/create/func_cases/mic_cr_qcow_logfile_conf_release_pkgmgr.case
@@ -11,7 +11,7 @@ losetup_path=$(sudo which losetup)
 
 sudo $losetup_path -a
 
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 
 # on some platforms, the command "setenforce 0" is needed to be executed,
 # on some other platforms, it's not needed to execute this command or
@@ -39,7 +39,11 @@ grep "Finished" /custome/arm.log
 
 sudo $losetup_path -a
 
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 
 test -f my_mic-output/tizen-2.2_20130719.3/images/qcow_image/emulimg-3.0.img
 
diff --git a/cases/create/func_cases/mic_cr_raw_generate-bmap_cp-knl_compress_runtime_local-pkgs_conf_armv7l.case b/cases/create/func_cases/mic_cr_raw_generate-bmap_cp-knl_compress_runtime_local-pkgs_conf_armv7l.case
index b7a9e71..0645f89 100755
--- a/cases/create/func_cases/mic_cr_raw_generate-bmap_cp-knl_compress_runtime_local-pkgs_conf_armv7l.case
+++ b/cases/create/func_cases/mic_cr_raw_generate-bmap_cp-knl_compress_runtime_local-pkgs_conf_armv7l.case
@@ -8,7 +8,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr raw ivi.ks \
   --generate-bmap \
   --compress-disk-image=bz2 \
@@ -21,7 +21,11 @@ sudo mic -d -v cr raw ivi.ks \
 grep "Finished" log.file
 
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 grep 'Marking .*.rpm to be installed' log.file
 
 ls -l ./my_mic-output | grep 'ivi.*-vmlinuz-*'
diff --git a/cases/create/func_cases/mic_cr_raw_gpt-part-type.case b/cases/create/func_cases/mic_cr_raw_gpt-part-type.case
index 5dcb9a5..339929e 100755
--- a/cases/create/func_cases/mic_cr_raw_gpt-part-type.case
+++ b/cases/create/func_cases/mic_cr_raw_gpt-part-type.case
@@ -6,14 +6,18 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 
 sudo mic -d -v cr raw ivi_gpt_with_part-type.ks --logfile=mic1.log
 
 grep 'Finished' mic1.log
 
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 
 test -f ./mic-output/ivi_gpt_with_part-type-*.raw
 ]]></steps>
diff --git a/cases/create/func_cases/mic_cr_raw_release_logfile_local-pkg-pth_record-pkg_gen-bmap_ia32.case b/cases/create/func_cases/mic_cr_raw_release_logfile_local-pkg-pth_record-pkg_gen-bmap_ia32.case
index 704a5b5..4792571 100755
--- a/cases/create/func_cases/mic_cr_raw_release_logfile_local-pkg-pth_record-pkg_gen-bmap_ia32.case
+++ b/cases/create/func_cases/mic_cr_raw_release_logfile_local-pkg-pth_record-pkg_gen-bmap_ia32.case
@@ -11,7 +11,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr raw ivi.ks \
   --local-pkgs-path=./rpm \
   --record-pkgs=name,content,license \
@@ -22,7 +22,11 @@ sudo mic -d -v cr raw ivi.ks \
 grep "Finished" log.file && echo 'mic command execution finished'
 
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 grep 'Marking .*.rpm to be installed' log.file
 
 sudo test -e ./log.file
diff --git a/cases/create/func_cases/mic_cr_scriptlet_error.case b/cases/create/func_cases/mic_cr_scriptlet_error.case
old mode 100644
new mode 100755
index e7786e2..219d96d
--- a/cases/create/func_cases/mic_cr_scriptlet_error.case
+++ b/cases/create/func_cases/mic_cr_scriptlet_error.case
@@ -12,13 +12,17 @@ cp  ./scriptlet/*  /home/build/scriptlet/
 createrepo /home/build/scriptlet
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 #zypp pkg manager 
 (! sudo mic -d -v cr loop scriptlet_error.ks --logfile=./log/handset.log)
 grep 'scriptlet errors occurred' ./log/handset.log
 grep 'The error install package info' ./log/handset.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
     ]]>
  </steps>
  <teardown>
diff --git a/cases/create/mixed_cases/check_install_packages_number_display.case b/cases/create/mixed_cases/check_install_packages_number_display.case
old mode 100644
new mode 100755
index c6a7619..67c1c7a
--- a/cases/create/mixed_cases/check_install_packages_number_display.case
+++ b/cases/create/mixed_cases/check_install_packages_number_display.case
@@ -12,12 +12,16 @@ installing package, before it shows error log 'install ....[15/14]'
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic cr loop handset_blackbay.ks --logfile=./log/handset.log
 test -f ./log/handset.log
 grep 'Finished' ./log/handset.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 grep 'Start mic in bootstrap' ./log/handset.log
 
 test -f ./mic-output/platform.img
diff --git a/cases/create/mixed_cases/mic_cr_auto_with_encoded_password.case b/cases/create/mixed_cases/mic_cr_auto_with_encoded_password.case
old mode 100644
new mode 100755
index 9b6daa4..31b72e7
--- a/cases/create/mixed_cases/mic_cr_auto_with_encoded_password.case
+++ b/cases/create/mixed_cases/mic_cr_auto_with_encoded_password.case
@@ -7,11 +7,15 @@
         <![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto handset_blackbay_with_encoded_passwd.ks --logfile=log.file
 grep "Finished" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 (! grep -i 'pass%40%2C%3A%25' log.file)
 ls mic-output/ | grep 'handset_blackbay_with_encoded_passwd-.*-rs.zip'
 ]]>
diff --git a/cases/create/mixed_cases/mic_cr_auto_with_separate_password.case b/cases/create/mixed_cases/mic_cr_auto_with_separate_password.case
old mode 100644
new mode 100755
index 1344956..3b2be0b
--- a/cases/create/mixed_cases/mic_cr_auto_with_separate_password.case
+++ b/cases/create/mixed_cases/mic_cr_auto_with_separate_password.case
@@ -6,12 +6,16 @@
     <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto handset_blackbay_with_separate_passwd.ks --logfile=log.file
 grep "Finished" log.file
 (! grep -i 'pass@,:%' log.file)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ls mic-output/ | grep 'handset_blackbay_with_separate_passwd-.*-rs.zip'
 ]]>
     </steps>
diff --git a/cases/create/mixed_cases/mic_cr_auto_with_un-encoded_password.case b/cases/create/mixed_cases/mic_cr_auto_with_un-encoded_password.case
old mode 100644
new mode 100755
index 15bfa2e..443f1af
--- a/cases/create/mixed_cases/mic_cr_auto_with_un-encoded_password.case
+++ b/cases/create/mixed_cases/mic_cr_auto_with_un-encoded_password.case
@@ -6,12 +6,16 @@
     <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto handset_blackbay_with_passwd.ks --logfile=log.file
 grep "Finished" log.file
 grep -i '123456' log.file && exit1
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ls mic-output/ | grep 'handset_blackbay_with_passwd-.*-rs.zip'
 ]]>
     </steps>
diff --git a/cases/create/mixed_cases/mic_cr_createrepo_issue.case b/cases/create/mixed_cases/mic_cr_createrepo_issue.case
old mode 100644
new mode 100755
diff --git a/cases/create/mixed_cases/mic_cr_fs_bootstrap_check_chroot.case b/cases/create/mixed_cases/mic_cr_fs_bootstrap_check_chroot.case
old mode 100644
new mode 100755
index 9122fd0..1d7153c
--- a/cases/create/mixed_cases/mic_cr_fs_bootstrap_check_chroot.case
+++ b/cases/create/mixed_cases/mic_cr_fs_bootstrap_check_chroot.case
@@ -7,12 +7,16 @@
     <![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr fs handset_blackbay.ks --logfile=./log/handset.log --runtime=bootstrap
 test -f ./log/handset.log
 grep 'Finished' ./log/handset.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 test -e ./mic-output/handset_blackbay*
 bash -c "sudo mic chroot ./mic-output/handset_blackbay*" << EOF
 echo "Checking chroot"
diff --git a/cases/create/mixed_cases/mic_cr_fs_check_high_version_rpm_installed.case b/cases/create/mixed_cases/mic_cr_fs_check_high_version_rpm_installed.case
old mode 100644
new mode 100755
index 1205e5d..9f5b444
--- a/cases/create/mixed_cases/mic_cr_fs_check_high_version_rpm_installed.case
+++ b/cases/create/mixed_cases/mic_cr_fs_check_high_version_rpm_installed.case
@@ -7,11 +7,15 @@
         <![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr fs handset_blackbay.ks --logfile=mic.log
 grep 'Finished' mic.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 hand_dir=$(ls mic-output | grep 'handset_blackbay')
 test -d mic-output/$hand_dir
 sudo chroot  mic-output/$hand_dir rpm -q bash | grep 4.3
diff --git a/cases/create/mixed_cases/mic_cr_fs_obsolete_pkg_test.case b/cases/create/mixed_cases/mic_cr_fs_obsolete_pkg_test.case
old mode 100644
new mode 100755
index a04bba8..6568885
--- a/cases/create/mixed_cases/mic_cr_fs_obsolete_pkg_test.case
+++ b/cases/create/mixed_cases/mic_cr_fs_obsolete_pkg_test.case
@@ -23,17 +23,25 @@
     sudo createrepo /home/build/tmp_repo2
     losetup_path=$(sudo which losetup)
     sudo $losetup_path -a
-    sudo $losetup_path -a | wc -l | xargs test 0 -eq
+    loop_used_before=$(sudo $losetup_path -a | wc -l)
     sudo mic -d -v cr fs obsolete_test_two.ks --logfile=mic1.log
     grep "Installing: A-.*" mic1.log
     grep "Installing: AA-.*" mic1.log
     sudo $losetup_path -a
-    sudo $losetup_path -a | wc -l | xargs test 0 -eq
+    loop_used_after=$(sudo $losetup_path -a | wc -l)
+    if [ "$loop_used_before" -ne "$loop_used_after" ];then
+        echo "Number of loop devices is not the same with previous number."
+        exit 1
+    fi
     sudo mic -d -v cr fs obsolete_test_one.ks --logfile=mic2.log
     (! grep "Installing: A-.*" mic2.log)
     grep "Installing: AAA-.*" mic2.log
     sudo $losetup_path -a
-    sudo $losetup_path -a | wc -l | xargs test 0 -eq
+    loop_used_after=$(sudo $losetup_path -a | wc -l)
+    if [ "$loop_used_before" -ne "$loop_used_after" ];then
+        echo "Number of loop devices is not the same with previous number."
+        exit 1
+    fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_fs_priority.case b/cases/create/mixed_cases/mic_cr_fs_priority.case
old mode 100644
new mode 100755
index e93e210..16a012c
--- a/cases/create/mixed_cases/mic_cr_fs_priority.case
+++ b/cases/create/mixed_cases/mic_cr_fs_priority.case
@@ -15,10 +15,14 @@ createrepo /home/build/tmp$i
 done
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr fs handset_blackbay_priority.ks --logfile=./log/handset.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 test -f ./log/handset.log
 grep 'Finished' ./log/handset.log
 sudo chroot ./mic-output/handset_blackbay_priority* rpm -qa fake | grep fake-1.0
diff --git a/cases/create/mixed_cases/mic_cr_fs_without_conf_bootstrap_ia32.case b/cases/create/mixed_cases/mic_cr_fs_without_conf_bootstrap_ia32.case
old mode 100644
new mode 100755
index 4ad0e63..57df4e3
--- a/cases/create/mixed_cases/mic_cr_fs_without_conf_bootstrap_ia32.case
+++ b/cases/create/mixed_cases/mic_cr_fs_without_conf_bootstrap_ia32.case
@@ -10,11 +10,15 @@ test -e /etc/mic/mic.conf
 sudo mv /etc/mic/mic.conf /etc/mic/mic.conf.bak
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 ! (sudo mic -d -v cr fs handset_blackbay.ks --logfile=handset.log --runtime=bootstrap) 2>&1 | tee mic.log
 grep -i "Failed to download/install bootstrap package" mic.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_bootstrap_check_chroot.case b/cases/create/mixed_cases/mic_cr_loop_bootstrap_check_chroot.case
old mode 100644
new mode 100755
index f40e3a4..2c71ff0
--- a/cases/create/mixed_cases/mic_cr_loop_bootstrap_check_chroot.case
+++ b/cases/create/mixed_cases/mic_cr_loop_bootstrap_check_chroot.case
@@ -6,13 +6,17 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --logfile=./log/handset.log
 test -f ./log/handset.log
 grep 'Finished' ./log/handset.log
 test -f ./mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 bash -c "sudo mic chroot ./mic-output/platform.img" << EOF
 echo "Checking chroot"
 ls
diff --git a/cases/create/mixed_cases/mic_cr_loop_check_arch.case b/cases/create/mixed_cases/mic_cr_loop_check_arch.case
old mode 100644
new mode 100755
index 7f832a3..588799b
--- a/cases/create/mixed_cases/mic_cr_loop_check_arch.case
+++ b/cases/create/mixed_cases/mic_cr_loop_check_arch.case
@@ -6,13 +6,17 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --logfile=mic.log
 grep 'Finished' mic.log
 grep 'Use detected arch i686' mic.log
 test -e mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_check_user_and_group_info.case b/cases/create/mixed_cases/mic_cr_loop_check_user_and_group_info.case
old mode 100644
new mode 100755
index 8c29438..5b003c1
--- a/cases/create/mixed_cases/mic_cr_loop_check_user_and_group_info.case
+++ b/cases/create/mixed_cases/mic_cr_loop_check_user_and_group_info.case
@@ -7,7 +7,7 @@ for output and cache directory, it's should be the current user</summary>
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks -o out1 -k cache --logfile=log.file
 grep "Finished" log.file
 c_user=$(whoami)
@@ -15,7 +15,11 @@ ls -l . | grep 'out1' | grep $c_user
 ls -l . | grep 'cache' | grep $c_user
 test -e out1/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_conf_etc_ia32.case b/cases/create/mixed_cases/mic_cr_loop_conf_etc_ia32.case
old mode 100644
new mode 100755
index ef49879..ab30b33
--- a/cases/create/mixed_cases/mic_cr_loop_conf_etc_ia32.case
+++ b/cases/create/mixed_cases/mic_cr_loop_conf_etc_ia32.case
@@ -5,10 +5,19 @@
     <copy src="conf/mic.conf" />
   </fixtures>
   <steps><![CDATA[
+losetup_path=$(sudo which losetup)
+sudo $losetup_path -a
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo cp mic.conf /etc
 sudo mic -d -v cr loop handset_blackbay.ks -c /etc/mic.conf --logfile=mic.log
 grep "Finished" mic.log
 sudo test -e ./mic-output/platform.img
+sudo $losetup_path -a
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_exclude-from-image.case b/cases/create/mixed_cases/mic_cr_loop_exclude-from-image.case
old mode 100644
new mode 100755
index ba27f08..821c119
--- a/cases/create/mixed_cases/mic_cr_loop_exclude-from-image.case
+++ b/cases/create/mixed_cases/mic_cr_loop_exclude-from-image.case
@@ -6,14 +6,18 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v --non-interactive cr loop  mobile_exclude.ks --logfile=log.file
 grep "Finished" log.file
 sudo test -e ./mic-output/u-boot-mmc.bin
 (! sudo test -e ./mic-output/boot.img)
 (! sudo test -e ./mic-output/modules.img)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_full_ks.case b/cases/create/mixed_cases/mic_cr_loop_full_ks.case
old mode 100644
new mode 100755
index ad7be9a..7d7f400
--- a/cases/create/mixed_cases/mic_cr_loop_full_ks.case
+++ b/cases/create/mixed_cases/mic_cr_loop_full_ks.case
@@ -21,7 +21,7 @@ assert manifest['loop']['partitions']['/opt/usr'] == 'ums'
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr auto whole_rd_210.ks --logfile=log.file
 grep "Finished" log.file
 sudo test -e ./mic-output/whole_rd_210-*.tar.gz
@@ -41,7 +41,11 @@ test $start_install_line -gt $end_preinstall_line
 mic_version=$(mic --version  2>&1 | awk -F ' ' '{print $2}')
 sudo python parse_manifest.py $img_file $mic_version
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_ks-under-root-directory_ia32.case b/cases/create/mixed_cases/mic_cr_loop_ks-under-root-directory_ia32.case
old mode 100644
new mode 100755
index ab08996..da1f774
--- a/cases/create/mixed_cases/mic_cr_loop_ks-under-root-directory_ia32.case
+++ b/cases/create/mixed_cases/mic_cr_loop_ks-under-root-directory_ia32.case
@@ -10,12 +10,16 @@
 sudo cp handset_blackbay.ks /
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop /handset_blackbay.ks --logfile=mic1.log
 grep 'Finished' mic1.log
 test -f ./mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_multi_partition.case b/cases/create/mixed_cases/mic_cr_loop_multi_partition.case
old mode 100644
new mode 100755
index 78299e9..e872901
--- a/cases/create/mixed_cases/mic_cr_loop_multi_partition.case
+++ b/cases/create/mixed_cases/mic_cr_loop_multi_partition.case
@@ -10,14 +10,18 @@ if [ ! -z $enforce_path ];then
 fi
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop RD-PQ.ks --logfile=log.file
 grep "Finished" log.file
 sudo test -e ./mic-output/platform.img
 sudo test -e ./mic-output/ums.img
 sudo test -e ./mic-output/data.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_no-cache.case b/cases/create/mixed_cases/mic_cr_loop_no-cache.case
old mode 100644
new mode 100755
index 621d2cb..9181b11
--- a/cases/create/mixed_cases/mic_cr_loop_no-cache.case
+++ b/cases/create/mixed_cases/mic_cr_loop_no-cache.case
@@ -6,7 +6,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks \
   --logfile=./log/handset1.log \
   -k /var/tmp/my_cache
@@ -14,14 +14,22 @@ test -f ./log/handset1.log
 grep 'Finished' ./log/handset1.log
 test -f ./mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo mic -d -v cr loop handset_blackbay.ks \
   --logfile=./log/handset2.log \
   -k /var/tmp/my_cache
 grep "43 Total, 43 Cached, 0 Missed"   ./log/handset2.log
 test -f ./mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 # Add "--nocache" to ks file
 sed -i '/repo/ s/$/ --nocache/' handset_blackbay.ks
 
@@ -32,7 +40,11 @@ grep "43 Total, 0 Cached, 43 Missed"   ./log/handset3.log
 grep "Finished" ./log/handset3.log
 test -f ./mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_only_local_repo.case b/cases/create/mixed_cases/mic_cr_loop_only_local_repo.case
old mode 100644
new mode 100755
index d47cfab..21b2c2c
--- a/cases/create/mixed_cases/mic_cr_loop_only_local_repo.case
+++ b/cases/create/mixed_cases/mic_cr_loop_only_local_repo.case
@@ -13,11 +13,15 @@ sudo umount /home/build/tmp/mic/cache || true
 sudo rm -rf /home/build/tmp/mic/cache
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --logfile=mic1.log
 grep "Finished" mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 pwd_dir=$(pwd)
 cd /home/build/tmp/mic/cache/packages/Tizen-base
 sudo createrepo .
@@ -28,7 +32,11 @@ sudo mic -d -v cr loop handset_blackbay_localrepo.ks -o out -k cache --logfile=m
 grep "Finished" mic2.log
 test -f out/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_overridden.case b/cases/create/mixed_cases/mic_cr_loop_overridden.case
old mode 100644
new mode 100755
index afab270..4a4ec76
--- a/cases/create/mixed_cases/mic_cr_loop_overridden.case
+++ b/cases/create/mixed_cases/mic_cr_loop_overridden.case
@@ -10,11 +10,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --logfile=handset_auto.log
 grep 'Finished' handset_auto.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 time1=`stat mic-output/platform.img | grep -E "Access: [0-9]" | awk '{print $3}'`
 sleep 20
 sudo mic -d -v cr loop handset_blackbay.ks --logfile=handset_auto_1.log
@@ -22,7 +26,11 @@ grep 'Finished' handset_auto_1.log
 time2=` stat mic-output/platform.img | grep -E "Access: [0-9]" | awk '{print $3}'`
 test "$time1" != "$time2"
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_pack-to-tar-gz_multi_times.case b/cases/create/mixed_cases/mic_cr_loop_pack-to-tar-gz_multi_times.case
old mode 100644
new mode 100755
index 8586282..2ebb7dd
--- a/cases/create/mixed_cases/mic_cr_loop_pack-to-tar-gz_multi_times.case
+++ b/cases/create/mixed_cases/mic_cr_loop_pack-to-tar-gz_multi_times.case
@@ -6,7 +6,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 for i in {1..10}; do
     sudo mic -d -v cr loop handset_blackbay.ks --pack-to=@NAME@.tar.gz --logfile=mic.log
     grep 'Finished' mic.log
@@ -18,7 +18,11 @@ for i in {1..10}; do
     echo "$i"
 done
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_release_ia32_bug.case b/cases/create/mixed_cases/mic_cr_loop_release_ia32_bug.case
old mode 100644
new mode 100755
index 083f801..27a8c18
--- a/cases/create/mixed_cases/mic_cr_loop_release_ia32_bug.case
+++ b/cases/create/mixed_cases/mic_cr_loop_release_ia32_bug.case
@@ -9,7 +9,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --release=tizen_20121223.1/ --logfile=mic.log
 grep "Finished" mic.log
 test -e ./mic-output/tizen_20121223.1/images/handset_blackbay*/platform.img
@@ -17,7 +17,11 @@ test -e ./mic-output/tizen_20121223.1/images/handset_blackbay*/MD5SUMS
 test -e ./mic-output/tizen_20121223.1/images/handset_blackbay*/tizen_20121223.1_handset_blackbay.packages
 test -e ./mic-output/tizen_20121223.1/images/handset_blackbay*/tizen_20121223.1_handset_blackbay.ks
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_repo_local_repo.case b/cases/create/mixed_cases/mic_cr_loop_repo_local_repo.case
old mode 100644
new mode 100755
index 37e5c33..91fcef8
--- a/cases/create/mixed_cases/mic_cr_loop_repo_local_repo.case
+++ b/cases/create/mixed_cases/mic_cr_loop_repo_local_repo.case
@@ -13,11 +13,15 @@ sudo umount /home/build/tmp/mic/cache || true
 sudo rm -rf /home/build/tmp/mic/cache
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --logfile=mic1.log
 grep "Finished" mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 pwd_dir=$(pwd)
 cd /home/build/tmp/mic/cache/packages/Tizen-base
 sudo createrepo .
@@ -28,7 +32,11 @@ sudo mic -d -v cr loop handset_blackbay_localrepo_test.ks --repo "name=local-mai
 grep "Finished" mic2.log
 test -e out1/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_tpk_local_repo.case b/cases/create/mixed_cases/mic_cr_loop_tpk_local_repo.case
old mode 100644
new mode 100755
index 7e2596f..24edcc8
--- a/cases/create/mixed_cases/mic_cr_loop_tpk_local_repo.case
+++ b/cases/create/mixed_cases/mic_cr_loop_tpk_local_repo.case
@@ -8,15 +8,23 @@ sudo mkdir -p /home/build/tmp/mic/tpk
 sudo wget -P /home/build/tmp/mic/tpk http://10.113.136.109/TPK/org.tizen.calendar-1.0.0-x86.tpk
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay_local_tpk_repo.ks --logfile=mic1.log
 grep "Finished" mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 grep "Finished" mic1.log
 test -e mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo mkdir -p ./mic-output/platform
 sudo mount ./mic-output/platform.img ./mic-output/platform
 sudo test -f ./mic-output/platform/usr/apps/.preload-tpk/org.tizen.calendar-1.0.0-x86.tpk
diff --git a/cases/create/mixed_cases/mic_cr_loop_without_conf_bootstrap_ia32.case b/cases/create/mixed_cases/mic_cr_loop_without_conf_bootstrap_ia32.case
old mode 100644
new mode 100755
index f6a59ee..280f2fa
--- a/cases/create/mixed_cases/mic_cr_loop_without_conf_bootstrap_ia32.case
+++ b/cases/create/mixed_cases/mic_cr_loop_without_conf_bootstrap_ia32.case
@@ -8,11 +8,15 @@ test -e /etc/mic/mic.conf
 sudo mv /etc/mic/mic.conf /etc/mic/mic.conf.bak
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 ! (sudo mic -d -v cr loop handset_blackbay.ks --logfile=handset.log --runtime=bootstrap) 2>&1 | tee mic.log
 grep -i "Failed to download/install bootstrap package" mic.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_loop_without_var_lock.case b/cases/create/mixed_cases/mic_cr_loop_without_var_lock.case
old mode 100644
new mode 100755
index 4c55b19..0d5cfb9
--- a/cases/create/mixed_cases/mic_cr_loop_without_var_lock.case
+++ b/cases/create/mixed_cases/mic_cr_loop_without_var_lock.case
@@ -13,11 +13,15 @@ if [ test -d /var/lock ];then
 fi
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --logfile=handset.log 2>&1 | tee all.log
 grep 'Finished' all.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_qcow_tpk_http_repo.case b/cases/create/mixed_cases/mic_cr_qcow_tpk_http_repo.case
old mode 100644
new mode 100755
index 2788eab..c36833c
--- a/cases/create/mixed_cases/mic_cr_qcow_tpk_http_repo.case
+++ b/cases/create/mixed_cases/mic_cr_qcow_tpk_http_repo.case
@@ -6,14 +6,22 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop qcow_image_tpk_http_repo.ks --logfile=mic1.log
 grep "Finished" mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 test -e mic-output/emulimg-3.0.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo mkdir -p ./mic-output/emulimg
 sudo mount ./mic-output/emulimg-3.0.img ./mic-output/emulimg
 sudo test -f ./mic-output/emulimg/usr/apps/.preload-tpk/org.tizen.camera-app-1.0.0-x86.tpk
diff --git a/cases/create/mixed_cases/mic_cr_raw_active_partition.case b/cases/create/mixed_cases/mic_cr_raw_active_partition.case
index 12f1371..79b0161 100755
--- a/cases/create/mixed_cases/mic_cr_raw_active_partition.case
+++ b/cases/create/mixed_cases/mic_cr_raw_active_partition.case
@@ -10,7 +10,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr raw ivi_with_active_partition.ks --logfile=log.file
 test -e ./log.file
 grep "Finished" log.file
@@ -53,7 +53,11 @@ else
     sudo $losetup_path -d $loop_device
 fi
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "clean space...."
diff --git a/cases/create/mixed_cases/mic_cr_raw_broken_bootstrap.case b/cases/create/mixed_cases/mic_cr_raw_broken_bootstrap.case
old mode 100644
new mode 100755
index d2ca819..e2d6e05
--- a/cases/create/mixed_cases/mic_cr_raw_broken_bootstrap.case
+++ b/cases/create/mixed_cases/mic_cr_raw_broken_bootstrap.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 (! sudo mic -d -v cr raw ivi_broken_content_bootstrap.ks --logfile=mic.log)
 grep -i 'Failed to download/install bootstrap package or the package is in bad format' mic.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_raw_installerfw_extlinux.case b/cases/create/mixed_cases/mic_cr_raw_installerfw_extlinux.case
old mode 100644
new mode 100755
index b9f0e4d..9b48b7c
--- a/cases/create/mixed_cases/mic_cr_raw_installerfw_extlinux.case
+++ b/cases/create/mixed_cases/mic_cr_raw_installerfw_extlinux.case
@@ -11,28 +11,40 @@ if [ "$platform" == "x86_64" ] || [ "$distro" == "centos" ]
 then
     losetup_path=$(sudo which losetup)
     sudo $losetup_path -a
-    sudo $losetup_path -a | wc -l | xargs test 0 -eq
+    loop_used_before=$(sudo $losetup_path -a | wc -l)
     sudo mic -d -v cr raw ivi_with_installerfw.ks --logfile=mic1.log
     grep 'Finished' mic1.log
     test -f ./mic-output/ivi_with_installerfw-*.raw
     sudo $losetup_path -a
-    sudo $losetup_path -a | wc -l | xargs test 0 -eq
+    loop_used_after=$(sudo $losetup_path -a | wc -l)
+    if [ "$loop_used_before" -ne "$loop_used_after" ];then
+        echo "Number of loop devices is not the same with previous number."
+        exit 1
+    fi
 else
     losetup_path=$(sudo which losetup)
     sudo $losetup_path -a
-    sudo $losetup_path -a | wc -l | xargs test 0 -eq
+    loop_used_before=$(sudo $losetup_path -a | wc -l)
     ! (sudo mic -d -v cr raw ivi_syslinux_problem.ks --logfile=log.file)
     sudo test -e ./log.file
     grep "Unable to install syslinux bootloader" log.file
     sed -i '/password/ a installerfw_plugins "bootloader"' ivi_syslinux_problem.ks
     sudo $losetup_path -a
-    sudo $losetup_path -a | wc -l | xargs test 0 -eq
+    loop_used_after=$(sudo $losetup_path -a | wc -l)
+    if [ "$loop_used_before" -ne "$loop_used_after" ];then
+        echo "Number of loop devices is not the same with previous number."
+        exit 1
+    fi
     sudo mic -d -v cr raw ivi_syslinux_problem.ks --logfile=new_log.file
     sudo test -e ./new_log.file
     grep "Finished" new_log.file
     test -f ./mic-output/ivi_syslinux_problem-*.raw
     sudo $losetup_path -a
-    sudo $losetup_path -a | wc -l | xargs test 0 -eq
+    loop_used_after=$(sudo $losetup_path -a | wc -l)
+    if [ "$loop_used_before" -ne "$loop_used_after" ];then
+        echo "Number of loop devices is not the same with previous number."
+        exit 1
+    fi
 
 fi
 ]]></steps>
diff --git a/cases/create/mixed_cases/mic_cr_raw_invliad_mic-bootstrap.case b/cases/create/mixed_cases/mic_cr_raw_invliad_mic-bootstrap.case
old mode 100644
new mode 100755
index 4da5cf8..2f75de3
--- a/cases/create/mixed_cases/mic_cr_raw_invliad_mic-bootstrap.case
+++ b/cases/create/mixed_cases/mic_cr_raw_invliad_mic-bootstrap.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 (! sudo mic -d -v cr raw ivi_invalid_content_mic-bootstrap.ks --logfile=mic.log)
 grep -i 'Failed to download/install bootstrap package or the package is in bad format' mic.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_raw_ivi_partition_size_compute_ia32.case b/cases/create/mixed_cases/mic_cr_raw_ivi_partition_size_compute_ia32.case
old mode 100644
new mode 100755
index 3a46797..cb921d8
--- a/cases/create/mixed_cases/mic_cr_raw_ivi_partition_size_compute_ia32.case
+++ b/cases/create/mixed_cases/mic_cr_raw_ivi_partition_size_compute_ia32.case
@@ -9,14 +9,18 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 distro=`python -c "import platform;a=platform.linux_distribution();print a[0]"`
 sudo mic -d -v cr raw ivi_624.ks --logfile=./log/handset.log 
 test -f ./log/handset.log
 grep 'Finished' ./log/handset.log
 test -e ./mic-output/ivi_624*.raw
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 if [ "$distro" == "CentOS" ]
 then
     parted ./mic-output/ivi*.raw print | grep -o "Disk.*" >> tmp1.log
diff --git a/cases/create/mixed_cases/mic_cr_raw_locale.case b/cases/create/mixed_cases/mic_cr_raw_locale.case
index f8f0699..a7c62ed 100755
--- a/cases/create/mixed_cases/mic_cr_raw_locale.case
+++ b/cases/create/mixed_cases/mic_cr_raw_locale.case
@@ -11,11 +11,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr raw ivi.ks --logfile=log.file
 grep "Finished" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 raw_image=$(ls mic-output/ivi-*-sdb.raw)
 sudo mkdir -p mic-output/ivi_dir/boot
 kpartx_path=$(sudo which kpartx)
diff --git a/cases/create/mixed_cases/mic_cr_raw_multi_partition_gpt.case b/cases/create/mixed_cases/mic_cr_raw_multi_partition_gpt.case
old mode 100644
new mode 100755
index 1e0f0f7..df2e4a9
--- a/cases/create/mixed_cases/mic_cr_raw_multi_partition_gpt.case
+++ b/cases/create/mixed_cases/mic_cr_raw_multi_partition_gpt.case
@@ -9,7 +9,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr raw ivi_four_partition_gpt.ks --logfile=log.file 
 sudo test -e ./log.file
 grep "Finished" log.file
@@ -18,7 +18,11 @@ raw_name=$(ls mic-output/ivi_four_partition_gpt-*-sdb.raw)
 parted_path=$(sudo which parted)
 sudo $parted_path  $raw_name print | grep "Partition Table: gpt"
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "clean space...."
diff --git a/cases/create/mixed_cases/mic_cr_raw_multi_partition_mbr.case b/cases/create/mixed_cases/mic_cr_raw_multi_partition_mbr.case
old mode 100644
new mode 100755
index 95368f9..ea2abe5
--- a/cases/create/mixed_cases/mic_cr_raw_multi_partition_mbr.case
+++ b/cases/create/mixed_cases/mic_cr_raw_multi_partition_mbr.case
@@ -9,7 +9,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr raw ivi_four_partition_mbr.ks --logfile=log.file
 test -e ./log.file
 grep "Finished" log.file
@@ -18,7 +18,11 @@ raw_name=$(ls ./mic-output/ivi_four_partition_mbr-*-sdb.raw)
 parted_path=$(sudo which parted)
 sudo $parted_path  $raw_name print | grep msdos
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "clean space...."
diff --git a/cases/create/mixed_cases/mic_cr_raw_no_mountpoint.case b/cases/create/mixed_cases/mic_cr_raw_no_mountpoint.case
old mode 100644
new mode 100755
index 40a96d6..8f073d5
--- a/cases/create/mixed_cases/mic_cr_raw_no_mountpoint.case
+++ b/cases/create/mixed_cases/mic_cr_raw_no_mountpoint.case
@@ -6,13 +6,17 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr raw ivi_no_mountpoint.ks --logfile=./log/ivi.log
 test -f ./log/ivi.log
 grep 'Finished' ./log/ivi.log
 test -f ./mic-output/ivi*.raw
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_raw_no_partition.case b/cases/create/mixed_cases/mic_cr_raw_no_partition.case
old mode 100644
new mode 100755
index 40e747d..28772c9
--- a/cases/create/mixed_cases/mic_cr_raw_no_partition.case
+++ b/cases/create/mixed_cases/mic_cr_raw_no_partition.case
@@ -7,13 +7,17 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr raw ivi_no_partition.ks --logfile=log.file
 test -e ./log.file
 grep "Finished" log.file
 sudo test -f ./mic-output/ivi_no_partition-*-sda.raw
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "clean space...."
diff --git a/cases/create/mixed_cases/mic_cr_raw_unicode.case b/cases/create/mixed_cases/mic_cr_raw_unicode.case
old mode 100644
new mode 100755
index 53a2224..4be7d4b
--- a/cases/create/mixed_cases/mic_cr_raw_unicode.case
+++ b/cases/create/mixed_cases/mic_cr_raw_unicode.case
@@ -6,13 +6,17 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 LANG=zh_CN.UTF-8
 sudo mic -d -v cr raw ivi.ks --logfile=mic1.log 
 grep 'Finished' mic1.log
 test -f ./mic-output/ivi*.raw
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_raw_without_conf_bootstrap_ia32.case b/cases/create/mixed_cases/mic_cr_raw_without_conf_bootstrap_ia32.case
old mode 100644
new mode 100755
index 9ff748e..4b1e003
--- a/cases/create/mixed_cases/mic_cr_raw_without_conf_bootstrap_ia32.case
+++ b/cases/create/mixed_cases/mic_cr_raw_without_conf_bootstrap_ia32.case
@@ -8,11 +8,15 @@ test -e /etc/mic/mic.conf
 sudo mv /etc/mic/mic.conf /etc/mic/mic.conf.bak
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 ! (sudo mic -d -v cr loop ivi.ks --logfile=ivi.log --runtime=bootstrap) 2>&1 | tee mic.log
 grep -i "Failed to download/install bootstrap package" mic.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/mixed_cases/mic_cr_strict_mode_image.case b/cases/create/mixed_cases/mic_cr_strict_mode_image.case
old mode 100644
new mode 100755
index 89570ab..cd0e679
--- a/cases/create/mixed_cases/mic_cr_strict_mode_image.case
+++ b/cases/create/mixed_cases/mic_cr_strict_mode_image.case
@@ -12,7 +12,7 @@ cp  ./strict_mode_rpm/*  /home/build/strict_mode/
 createrepo /home/build/strict_mode
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 #zypp pkg manager
 sudo mic -d -v cr loop strict_mode.ks --logfile=./log/handset.log
 grep 'Finished' ./log/handset.log
@@ -20,7 +20,11 @@ grep 'Finished' ./log/handset.log
 (! sudo mic -d -v cr loop strict_mode.ks --logfile=./log/handset.log --strict-mode)
 grep 'mic failes to install some packages' ./log/handset.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
     ]]>
  </steps>
  <teardown>
diff --git a/cases/create/mixed_cases/mic_duplicate_log.case b/cases/create/mixed_cases/mic_duplicate_log.case
old mode 100644
new mode 100755
diff --git a/cases/create/mixed_cases/mic_man_page.case b/cases/create/mixed_cases/mic_man_page.case
old mode 100644
new mode 100755
diff --git a/cases/create/neg_cases/mic_cr_auto_loop_script_error.case b/cases/create/neg_cases/mic_cr_auto_loop_script_error.case
old mode 100644
new mode 100755
index ac93a74..2c70011
--- a/cases/create/neg_cases/mic_cr_auto_loop_script_error.case
+++ b/cases/create/neg_cases/mic_cr_auto_loop_script_error.case
@@ -10,11 +10,15 @@ which called magic line, and magic line in this ks file is:
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 (! sudo mic cr auto handset_blackbay_script_error.ks --logfile=log.file)
 grep "/usr/bin/error_command" log.file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/neg_cases/mic_cr_failed_release_log.case b/cases/create/neg_cases/mic_cr_failed_release_log.case
index cb54951..175d380 100755
--- a/cases/create/neg_cases/mic_cr_failed_release_log.case
+++ b/cases/create/neg_cases/mic_cr_failed_release_log.case
@@ -6,7 +6,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 ! (sudo mic -d -v cr auto error_no_package.ks --release=tizen-2.0_20130311.2)
 sudo test -e mic-output/tizen-2.0_20130311.2/images/error_no_package/tizen-2.0_20130311.2_error_no_package.log
 ! (grep -L "Finished" mic-output/tizen-2.0_20130311.2/images/error_no_package/tizen-2.0_20130311.2_error_no_package.log)
@@ -26,7 +26,11 @@ sudo test -e mic-output/tizen-2.0_20130311.2/images/error_no_package/tizen-2.0_2
 ls mic-output/tizen-2.0_20130311.2/images/error_no_package | wc -l | xargs test 9 -eq
 grep "Finished" mic-output/tizen-2.0_20130311.2/images/error_no_package/tizen-2.0_20130311.2_error_no_package.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/neg_cases/mic_cr_fs_no_mountpoint.case b/cases/create/neg_cases/mic_cr_fs_no_mountpoint.case
old mode 100644
new mode 100755
index c2436f7..c5999ea
--- a/cases/create/neg_cases/mic_cr_fs_no_mountpoint.case
+++ b/cases/create/neg_cases/mic_cr_fs_no_mountpoint.case
@@ -7,13 +7,17 @@
     <![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr fs handset_blackbay_no_mountpoint.ks --logfile=./log/handset.log
 test -f ./log/handset.log
 grep -i 'Finished' ./log/handset.log
 test -d ./mic-output/handset_blackbay_no_mountpoint*
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown>
     <![CDATA[
diff --git a/cases/create/neg_cases/mic_cr_loop_compress-image_wrong-format.case b/cases/create/neg_cases/mic_cr_loop_compress-image_wrong-format.case
old mode 100644
new mode 100755
index d8fddb8..0f5a076
--- a/cases/create/neg_cases/mic_cr_loop_compress-image_wrong-format.case
+++ b/cases/create/neg_cases/mic_cr_loop_compress-image_wrong-format.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --compress-image=az4 -o out2 --logfile=mic2.log 2>&1 | tee mic.log || true
 grep -i "invalid choice.*az4.*" mic.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/neg_cases/negative_command_without_ks_file.case b/cases/create/neg_cases/negative_command_without_ks_file.case
old mode 100644
new mode 100755
index bbe956d..140558d
--- a/cases/create/neg_cases/negative_command_without_ks_file.case
+++ b/cases/create/neg_cases/negative_command_without_ks_file.case
@@ -4,7 +4,6 @@
 set +e
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
 sudo mic -d -v cr fs 2>> mic1.log
 grep -i "too few arguments" mic1.log 
 ]]></steps>
diff --git a/cases/create/neg_cases/negative_error-ks-with-chinese.case b/cases/create/neg_cases/negative_error-ks-with-chinese.case
old mode 100644
new mode 100755
index a47e243..8045b3a
--- a/cases/create/neg_cases/negative_error-ks-with-chinese.case
+++ b/cases/create/neg_cases/negative_error-ks-with-chinese.case
@@ -7,12 +7,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 export LC_ALL=zh_CN.utf-8
 (! sudo mic -d -v cr auto error_ks_with_chinese.ks --logfile=mic1.log)
 grep -i 'Unable to find package: 你好' mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "clean space...."
diff --git a/cases/create/neg_cases/negative_error-package-ks.case b/cases/create/neg_cases/negative_error-package-ks.case
old mode 100644
new mode 100755
index 62cb898..20c63f6
--- a/cases/create/neg_cases/negative_error-package-ks.case
+++ b/cases/create/neg_cases/negative_error-package-ks.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 (! sudo mic -d -v cr auto error_package.ks --logfile=mic1.log)
 grep -i 'Unable to find package: svn' mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "clean space...."
diff --git a/cases/create/neg_cases/negative_error-repo-ks.case b/cases/create/neg_cases/negative_error-repo-ks.case
old mode 100644
new mode 100755
index d3165cb..a44f93b
--- a/cases/create/neg_cases/negative_error-repo-ks.case
+++ b/cases/create/neg_cases/negative_error-repo-ks.case
@@ -6,14 +6,18 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 (! sudo mic -d -v cr auto error_repo.ks --logfile=mic1.log )
 grep 'URLGrabber error' mic1.log || \
   grep 'PYCURL ERROR' mic1.log || \
   grep 'HTTP Error' mic1.log  || \
   grep '404 Not Found' mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "clean space...."
diff --git a/cases/create/neg_cases/negative_error_proxy_conf.case b/cases/create/neg_cases/negative_error_proxy_conf.case
old mode 100644
new mode 100755
index 700ae71..66cdb62
--- a/cases/create/neg_cases/negative_error_proxy_conf.case
+++ b/cases/create/neg_cases/negative_error_proxy_conf.case
@@ -7,11 +7,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 (! sudo mic -d -v cr loop handset_blackbay.ks -c mic_error.conf 2>&1 | tee mic1.log)
 grep -i "[URLGrabber error|PYCURL ERROR|HTTP Error|couldn't connect]" mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "clean space...."
diff --git a/cases/create/neg_cases/negative_error_proxy_conf_logfile.case b/cases/create/neg_cases/negative_error_proxy_conf_logfile.case
old mode 100644
new mode 100755
index ff7df20..0544058
--- a/cases/create/neg_cases/negative_error_proxy_conf_logfile.case
+++ b/cases/create/neg_cases/negative_error_proxy_conf_logfile.case
@@ -10,11 +10,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 (! sudo mic -d -v cr loop handset_blackbay.ks -c mic_error.conf --logfile=error.log)
 grep -i "[URLGrabber error|PYCURL ERROR|HTTP Error|couldn't connect]" error.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "clean space...."
diff --git a/cases/create/neg_cases/negative_mic_cr_auto_without_autoline.case b/cases/create/neg_cases/negative_mic_cr_auto_without_autoline.case
old mode 100644
new mode 100755
index fb173a7..342bb34
--- a/cases/create/neg_cases/negative_mic_cr_auto_without_autoline.case
+++ b/cases/create/neg_cases/negative_mic_cr_auto_without_autoline.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 (! sudo mic -d -v cr auto error_auto.ks --logfile=mic1.log)
 grep -i 'Invalid magic line in file' mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "clean space...."
diff --git a/cases/create/neg_cases/negative_no-package-ks.case b/cases/create/neg_cases/negative_no-package-ks.case
old mode 100644
new mode 100755
index c2c1104..4f84817
--- a/cases/create/neg_cases/negative_no-package-ks.case
+++ b/cases/create/neg_cases/negative_no-package-ks.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 (! sudo mic -d -v cr loop error_no_package.ks --logfile=mic1.log)
 grep -i 'No packages or groups specified' mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "clean space...."
diff --git a/cases/create/neg_cases/negative_no-repo-ks.case b/cases/create/neg_cases/negative_no-repo-ks.case
old mode 100644
new mode 100755
index 2df48b6..e3538ad
--- a/cases/create/neg_cases/negative_no-repo-ks.case
+++ b/cases/create/neg_cases/negative_no-repo-ks.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 (! sudo mic -d -v cr loop error_no_repo.ks --logfile=mic1.log)
 grep -i 'no valid repos found in ks file' mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "clean space...."
diff --git a/cases/create/neg_cases/negative_non-existed-package.case b/cases/create/neg_cases/negative_non-existed-package.case
old mode 100644
new mode 100755
index 2d74de7..8deae7e
--- a/cases/create/neg_cases/negative_non-existed-package.case
+++ b/cases/create/neg_cases/negative_non-existed-package.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sed -i '/\%packages/a\hellokitty' handset_blackbay.ks
 (! sudo mic -d -v cr auto handset_blackbay.ks --logfile=mic1.log)
 grep -i "Unable to find package: hellokitty" mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "clean space...."
diff --git a/cases/create/opt_cases/mic_cr_fs_include-src_ia32.case b/cases/create/opt_cases/mic_cr_fs_include-src_ia32.case
old mode 100644
new mode 100755
index 08b97f1..be6c1a1
--- a/cases/create/opt_cases/mic_cr_fs_include-src_ia32.case
+++ b/cases/create/opt_cases/mic_cr_fs_include-src_ia32.case
@@ -7,11 +7,15 @@
         <![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr fs handset_blackbay.ks --include-src  --logfile=mic1.log
 grep 'Finished' mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 test -d ./mic-output/handset_blackbay*
 sudo chroot ./mic-output/handset_blackbay* ls /usr/src/SRPMS/ | grep ".*\.rpm"
         ]]>
diff --git a/cases/create/opt_cases/mic_cr_fs_record-pkgs-name-content-license-vcs_ia32.case b/cases/create/opt_cases/mic_cr_fs_record-pkgs-name-content-license-vcs_ia32.case
old mode 100644
new mode 100755
index c71722a..b4d4a4a
--- a/cases/create/opt_cases/mic_cr_fs_record-pkgs-name-content-license-vcs_ia32.case
+++ b/cases/create/opt_cases/mic_cr_fs_record-pkgs-name-content-license-vcs_ia32.case
@@ -7,12 +7,16 @@
         <![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr fs handset_blackbay.ks --record-pkgs=name,content,license,vcs  --logfile=mic.log
 grep 'Finished' mic.log
 test -d ./mic-output/handset_blackbay*[0-9]
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 cat ./mic-output/handset_blackbay*.packages | grep bash
 cat ./mic-output/handset_blackbay*.license | grep bash
 cat ./mic-output/handset_blackbay*.files | grep bash
diff --git a/cases/create/opt_cases/mic_cr_fs_runtime-bootstrap_ia32.case b/cases/create/opt_cases/mic_cr_fs_runtime-bootstrap_ia32.case
old mode 100644
new mode 100755
index 7201da1..bf174c7
--- a/cases/create/opt_cases/mic_cr_fs_runtime-bootstrap_ia32.case
+++ b/cases/create/opt_cases/mic_cr_fs_runtime-bootstrap_ia32.case
@@ -7,14 +7,18 @@
         <![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr fs handset_blackbay.ks --runtime=bootstrap  --logfile=mic.log
 grep 'Start mic in bootstrap' mic.log
 grep 'Finished' mic.log
 image_name=`ls ./mic-output | grep 'handset_blackbay*'`
 test -d ./mic-output/$image_name
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
         ]]>
     </steps>
     <teardown>
diff --git a/cases/create/opt_cases/mic_cr_loop_arc-invalid_ia32.case b/cases/create/opt_cases/mic_cr_loop_arc-invalid_ia32.case
old mode 100644
new mode 100755
index 69b0130..ff05299
--- a/cases/create/opt_cases/mic_cr_loop_arc-invalid_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_arc-invalid_ia32.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 ! (sudo mic -d -v cr loop handset_blackbay.ks -A i286 --logfile=mic1.log)
 grep "Invalid architecture" mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_arc_ia32.case b/cases/create/opt_cases/mic_cr_loop_arc_ia32.case
old mode 100644
new mode 100755
index 7924d60..b197ebd
--- a/cases/create/opt_cases/mic_cr_loop_arc_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_arc_ia32.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks -A i686 --logfile=log.file
 grep "Finished" log.file
 test -e ./mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_arch-vague_ia32.case b/cases/create/opt_cases/mic_cr_loop_arch-vague_ia32.case
old mode 100644
new mode 100755
index 01a4e7e..12a4488
--- a/cases/create/opt_cases/mic_cr_loop_arch-vague_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_arch-vague_ia32.case
@@ -6,7 +6,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 enforce_path=$(sudo which setenforce || true)
 if [ ! -z $enforce_path ];then
     sudo $enforce_path 0 || true
@@ -15,7 +15,11 @@ sudo mic -d -v cr loop armv7l_with_arch.ks -A armv7l -o out1 --logfile=mic1.log
 grep 'Finished' mic1.log
 grep 'armv7l' mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 test -f ./out1/platform.img
 ]]></steps>
   <teardown><![CDATA[
diff --git a/cases/create/opt_cases/mic_cr_loop_cache-current-dir_ia32.case b/cases/create/opt_cases/mic_cr_loop_cache-current-dir_ia32.case
old mode 100644
new mode 100755
index fa10644..38cdf76
--- a/cases/create/opt_cases/mic_cr_loop_cache-current-dir_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_cache-current-dir_ia32.case
@@ -7,13 +7,17 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --cachedir=./cache/mic_cache --logfile=file.log
 grep 'Finished' file.log
 test -f ./mic-output/platform.img
 test -d ./cache/mic_cache
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_cache-root-dir_ia32.case b/cases/create/opt_cases/mic_cr_loop_cache-root-dir_ia32.case
old mode 100644
new mode 100755
index 1fd496f..2aba2b2
--- a/cases/create/opt_cases/mic_cr_loop_cache-root-dir_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_cache-root-dir_ia32.case
@@ -14,12 +14,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks -k /root/cache/mic_cache --logfile=file.log
 grep 'Finished' file.log
 grep "43 Total, 0 Cached, 43 Missed" file.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo test -d /root/cache/mic_cache
 test -f ./mic-output/platform.img
 sudo rm -rf file.log
@@ -28,7 +32,11 @@ sudo mic -d -v cr loop handset_blackbay.ks -k /root/cache/mic_cache --logfile=fi
 grep 'Finished' file.log
 test -f ./mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 grep "43 Total, 43 Cached, 0 Missed" file.log
 ]]></steps>
   <teardown><![CDATA[
diff --git a/cases/create/opt_cases/mic_cr_loop_compress-image-bz2_ia32.case b/cases/create/opt_cases/mic_cr_loop_compress-image-bz2_ia32.case
old mode 100644
new mode 100755
index 52b87f1..036ca49
--- a/cases/create/opt_cases/mic_cr_loop_compress-image-bz2_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_compress-image-bz2_ia32.case
@@ -7,17 +7,25 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks -o out1 --logfile=mic1.log
 grep 'Finished' mic1.log
 test -f ./out1/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo mic -d -v cr loop handset_blackbay.ks --compress-image=bz2 -o out2 --logfile=mic2.log
 grep 'Finished' mic2.log
 test -f ./out2/platform.img.bz2
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 source compute_volume.sh
 p1=`compute_volume ./out1/platform.img`
 p2=`compute_volume ./out2/platform.img.bz2`
diff --git a/cases/create/opt_cases/mic_cr_loop_compress-image-gz_ia32.case b/cases/create/opt_cases/mic_cr_loop_compress-image-gz_ia32.case
old mode 100644
new mode 100755
index f767185..de6197c
--- a/cases/create/opt_cases/mic_cr_loop_compress-image-gz_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_compress-image-gz_ia32.case
@@ -7,17 +7,25 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks -o out1 --logfile=mic1.log
 grep 'Finished' mic1.log
 test -f ./out1/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo mic -d -v cr loop handset_blackbay.ks --compress-image=gz -o out2 --logfile=mic2.log
 grep 'Finished' mic2.log
 test -f ./out2/platform.img.gz
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 source compute_volume.sh
 p1=`compute_volume ./out1/platform.img`
 p2=`compute_volume ./out2/platform.img.gz`
diff --git a/cases/create/opt_cases/mic_cr_loop_compress-image-invalid_ia32.case b/cases/create/opt_cases/mic_cr_loop_compress-image-invalid_ia32.case
old mode 100644
new mode 100755
index 75772a3..a800ac5
--- a/cases/create/opt_cases/mic_cr_loop_compress-image-invalid_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_compress-image-invalid_ia32.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 ! (sudo mic -d -v cr loop handset_blackbay.ks --compress-image=zip  2>&1 | tee mic2.log)
 grep -E "compress-image: invalid choice: 'zip'" mic2.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_conf_ia32.case b/cases/create/opt_cases/mic_cr_loop_conf_ia32.case
old mode 100644
new mode 100755
index fc2e887..9d1fe92
--- a/cases/create/opt_cases/mic_cr_loop_conf_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_conf_ia32.case
@@ -9,12 +9,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks -c mic.conf --logfile=log.file
 grep "Finished" log.file
 test -f ./my_mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_copy-kernel_ia32.case b/cases/create/opt_cases/mic_cr_loop_copy-kernel_ia32.case
old mode 100644
new mode 100755
index 822aad1..5b585da
--- a/cases/create/opt_cases/mic_cr_loop_copy-kernel_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_copy-kernel_ia32.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --copy-kernel --logfile=mic.log
 grep 'Finished' mic.log
 test -f ./mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ls -l ./mic-output | grep -E 'handset_blackbay.*vm.*'
 ]]></steps>
   <teardown><![CDATA[
diff --git a/cases/create/opt_cases/mic_cr_loop_debug_ia32.case b/cases/create/opt_cases/mic_cr_loop_debug_ia32.case
old mode 100644
new mode 100755
index 39a64d9..4e2153e
--- a/cases/create/opt_cases/mic_cr_loop_debug_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_debug_ia32.case
@@ -6,7 +6,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 enforce_path=$(sudo which setenforce || true)
 if [ ! -z $enforce_path ];then
     sudo $enforce_path 0 || true
@@ -15,7 +15,11 @@ sudo mic -d -v cr loop armv7l.ks -o out1  2>&1 | tee mic1.log
 grep -i 'Finished' mic1.log
 grep -i 'Debug' mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 grep -i 'Verbose' mic1.log
 test -f ./out1/platform.img
 ]]></steps>
diff --git a/cases/create/opt_cases/mic_cr_loop_interactive_ia32.case b/cases/create/opt_cases/mic_cr_loop_interactive_ia32.case
old mode 100644
new mode 100755
index 0893498..d499637
--- a/cases/create/opt_cases/mic_cr_loop_interactive_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_interactive_ia32.case
@@ -6,18 +6,26 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sed -i '/shadow-utils/d' handset_blackbay.ks
 sudo mic --non-interactive cr loop handset_blackbay.ks 
 test -f ./mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 bash -c "sudo mic -i cr loop handset_blackbay.ks 2>&1 >> tmp.log" << EOF
 n
 EOF
 grep ".* \[y/n](y): INFO" tmp.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 
 ]]></steps>
   <teardown><![CDATA[
diff --git a/cases/create/opt_cases/mic_cr_loop_local-pkg-path_ia32.case b/cases/create/opt_cases/mic_cr_loop_local-pkg-path_ia32.case
old mode 100644
new mode 100755
index e1b21a7..4d38dda
--- a/cases/create/opt_cases/mic_cr_loop_local-pkg-path_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_local-pkg-path_ia32.case
@@ -8,13 +8,17 @@
         <![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr fs handset_blackbay.ks --local-pkgs-path=./rpm --logfile=./log/handset.log
 test -f ./log/handset.log
 grep 'Finished' ./log/handset.log
 test -e ./mic-output/handset_blackbay*[0-9]
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo chroot ./mic-output/handset_blackbay*[0-9] rpm -qa | grep "sed"
         ]]>
     </steps>
diff --git a/cases/create/opt_cases/mic_cr_loop_logfile-current-dir_ia32.case b/cases/create/opt_cases/mic_cr_loop_logfile-current-dir_ia32.case
old mode 100644
new mode 100755
index 448a5c8..1ef3f29
--- a/cases/create/opt_cases/mic_cr_loop_logfile-current-dir_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_logfile-current-dir_ia32.case
@@ -11,14 +11,18 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 hostname=$(hostname)
 mkdir ./log_dir
 ! (sudo mic -d -v cr loop handset_blackbay.ks --logfile=./log_dir 2>&1 | tee  mic.log )
 grep -i "./log_dir should be file"  mic.log
 grep "$hostname" mic.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_logfile-current-file_ia32.case b/cases/create/opt_cases/mic_cr_loop_logfile-current-file_ia32.case
old mode 100644
new mode 100755
index f704bdc..78500e8
--- a/cases/create/opt_cases/mic_cr_loop_logfile-current-file_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_logfile-current-file_ia32.case
@@ -8,14 +8,18 @@ There is no need to give an existed file name, mic will create a new file with t
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 hostname=$(hostname)
 sudo mic -d -v cr loop handset_blackbay.ks --logfile=./log/handset.log
 test -f ./log/handset.log
 grep 'Finished' ./log/handset.log
 grep "$hostname" ./log/handset.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 egrep 'mic [0-9]{1,2}\.[0-9]+' ./log/handset.log
 test -f ./mic-output/platform.img
 ]]></steps>
diff --git a/cases/create/opt_cases/mic_cr_loop_logfile-root-file_ia32.case b/cases/create/opt_cases/mic_cr_loop_logfile-root-file_ia32.case
old mode 100644
new mode 100755
index 5763bc7..03470f8
--- a/cases/create/opt_cases/mic_cr_loop_logfile-root-file_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_logfile-root-file_ia32.case
@@ -6,13 +6,17 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 hostname=$(hostname)
 sudo mic -d -v cr loop handset_blackbay.ks --logfile=/root/log_file  >> mic.log
 grep "Finished" mic.log
 sudo test -e /root/log_file
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo egrep "$hostname" /root/log_file
 sudo egrep 'mic [0-9]{1,2}\.[0-9]+' /root/log_file
 sudo test -e ./mic-output/platform.img
diff --git a/cases/create/opt_cases/mic_cr_loop_outdir-current-dir_ia32.case b/cases/create/opt_cases/mic_cr_loop_outdir-current-dir_ia32.case
old mode 100644
new mode 100755
index a4e92d0..3bd560a
--- a/cases/create/opt_cases/mic_cr_loop_outdir-current-dir_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_outdir-current-dir_ia32.case
@@ -7,12 +7,16 @@ it can be set to an existed directory and also can be set to an unexisted direct
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --outdir=my_mic_out  --logfile=log.file
 grep "Finished" log.file
 if [ -e my_mic_out/platform.img ]; then echo " Image found. " ; else echo "Image not found." && exit 1 ; fi
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_outdir-root-dir_ia32.case b/cases/create/opt_cases/mic_cr_loop_outdir-root-dir_ia32.case
old mode 100644
new mode 100755
index 6f08140..1ca8120
--- a/cases/create/opt_cases/mic_cr_loop_outdir-root-dir_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_outdir-root-dir_ia32.case
@@ -7,12 +7,16 @@ a subdirectory under /root is given to it, related images should can be found un
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks -o /root/my_mic_out  --logfile=log.file
 grep "Finished" log.file
 sudo test -f /root/my_mic_out/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_pack-to-Invalid_ia32.case b/cases/create/opt_cases/mic_cr_loop_pack-to-Invalid_ia32.case
old mode 100644
new mode 100755
index 3600032..a3b7ade
--- a/cases/create/opt_cases/mic_cr_loop_pack-to-Invalid_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_pack-to-Invalid_ia32.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 (! sudo mic -d -v cr loop handset_blackbay.ks --pack-to=@NAME@.bz2  --logfile=mic.log)
 grep 'Not supported archive file format' mic.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_pack-to-tar-bz2_ia32.case b/cases/create/opt_cases/mic_cr_loop_pack-to-tar-bz2_ia32.case
old mode 100644
new mode 100755
index 73b0967..1b75ddf
--- a/cases/create/opt_cases/mic_cr_loop_pack-to-tar-bz2_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_pack-to-tar-bz2_ia32.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --pack-to=@NAME@.tar.bz2 --logfile=mic.log
 grep 'Finished' mic.log
 test -f ./mic-output/handset_blackbay*.tar.bz2
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo bunzip2 -d ./mic-output/handset_blackbay*.tar.bz2
 sudo tar -xvf ./mic-output/handset_blackbay*.tar -C ./mic-output
 sudo test -e ./mic-output/platform.img
diff --git a/cases/create/opt_cases/mic_cr_loop_pack-to-tar-bz_ia32.case b/cases/create/opt_cases/mic_cr_loop_pack-to-tar-bz_ia32.case
old mode 100644
new mode 100755
index af96b7c..9177092
--- a/cases/create/opt_cases/mic_cr_loop_pack-to-tar-bz_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_pack-to-tar-bz_ia32.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr  loop handset_blackbay.ks --pack-to=@NAME@.tar.bz --logfile=mic.log
 grep 'Finished' mic.log
 test -f ./mic-output/handset_blackbay*.tar.bz
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo bunzip2 -d ./mic-output/handset_blackbay*.tar.bz
 sudo tar -xvf ./mic-output/handset_blackbay*.tar -C ./mic-output
 sudo test -e ./mic-output/platform.img
diff --git a/cases/create/opt_cases/mic_cr_loop_pack-to-tar-gz_ia32.case b/cases/create/opt_cases/mic_cr_loop_pack-to-tar-gz_ia32.case
old mode 100644
new mode 100755
index c86bf5a..3663f97
--- a/cases/create/opt_cases/mic_cr_loop_pack-to-tar-gz_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_pack-to-tar-gz_ia32.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --pack-to=@NAME@.tar.gz  --logfile=mic.log
 grep 'Finished' mic.log
 test -f ./mic-output/handset_blackbay*.tar.gz
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo gunzip  ./mic-output/handset_blackbay*.tar.gz
 sudo tar -xvf ./mic-output/handset_blackbay*.tar -C ./mic-output
 sudo test -e ./mic-output/platform.img
diff --git a/cases/create/opt_cases/mic_cr_loop_pack-to-tar_ia32.case b/cases/create/opt_cases/mic_cr_loop_pack-to-tar_ia32.case
old mode 100644
new mode 100755
index a097042..2b2f6ce
--- a/cases/create/opt_cases/mic_cr_loop_pack-to-tar_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_pack-to-tar_ia32.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --pack-to=@NAME@.tar  --logfile=mic.log
 grep 'Finished' mic.log
 test -f ./mic-output/handset_blackbay*.tar
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo tar -xvf ./mic-output/handset_blackbay*.tar -C ./mic-output
 sudo test -f ./mic-output/platform.img
 ]]></steps>
diff --git a/cases/create/opt_cases/mic_cr_loop_pack-to-taz.case b/cases/create/opt_cases/mic_cr_loop_pack-to-taz.case
old mode 100644
new mode 100755
index 5ea85c4..65ab9e6
--- a/cases/create/opt_cases/mic_cr_loop_pack-to-taz.case
+++ b/cases/create/opt_cases/mic_cr_loop_pack-to-taz.case
@@ -6,14 +6,18 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr  loop handset_blackbay.ks \
   --pack-to=@NAME@.taz \
   --logfile=mic.log
 grep 'Finished' mic.log
 test -f ./mic-output/handset_blackbay*.taz
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo gunzip mic-output/handset_blackbay*.taz
 sudo tar -xvf ./mic-output/handset_blackbay*.tar -C ./mic-output
 sudo test -e ./mic-output/platform.img
diff --git a/cases/create/opt_cases/mic_cr_loop_pack-to-tbz2_ia32.case b/cases/create/opt_cases/mic_cr_loop_pack-to-tbz2_ia32.case
old mode 100644
new mode 100755
index 7dda1b2..05c2cd7
--- a/cases/create/opt_cases/mic_cr_loop_pack-to-tbz2_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_pack-to-tbz2_ia32.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --pack-to=@NAME@.tbz2 --logfile=mic.log
 grep 'Finished' mic.log
 test -f ./mic-output/handset_blackbay*.tbz2
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo bunzip2 -d ./mic-output/handset_blackbay*.tbz2
 sudo tar -xvf ./mic-output/handset_blackbay*.tar -C ./mic-output
 sudo test -e ./mic-output/platform.img
diff --git a/cases/create/opt_cases/mic_cr_loop_pack-to-tbz_ia32.case b/cases/create/opt_cases/mic_cr_loop_pack-to-tbz_ia32.case
old mode 100644
new mode 100755
index 0f67826..d5271b3
--- a/cases/create/opt_cases/mic_cr_loop_pack-to-tbz_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_pack-to-tbz_ia32.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --pack-to=@NAME@.tbz --logfile=mic.log
 grep 'Finished' mic.log
 test -f ./mic-output/handset_blackbay*.tbz
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo bunzip2 -d ./mic-output/handset_blackbay*.tbz
 sudo tar -xvf ./mic-output/handset_blackbay*.tar -C ./mic-output
 sudo test -e ./mic-output/platform.img
diff --git a/cases/create/opt_cases/mic_cr_loop_pack-to-tgz.case b/cases/create/opt_cases/mic_cr_loop_pack-to-tgz.case
old mode 100644
new mode 100755
index cd428a9..c4aa513
--- a/cases/create/opt_cases/mic_cr_loop_pack-to-tgz.case
+++ b/cases/create/opt_cases/mic_cr_loop_pack-to-tgz.case
@@ -6,14 +6,18 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks \
   --pack-to=@NAME@.tgz \
   --logfile=mic.log
 grep 'Finished' mic.log
 test -f ./mic-output/handset_blackbay*.tgz
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo gunzip ./mic-output/handset_blackbay*.tgz
 sudo tar -xvf ./mic-output/handset_blackbay*.tar -C ./mic-output
 sudo test -e ./mic-output/platform.img
diff --git a/cases/create/opt_cases/mic_cr_loop_pack-to-zip_ia32.case b/cases/create/opt_cases/mic_cr_loop_pack-to-zip_ia32.case
old mode 100644
new mode 100755
index 11cffb6..9e3125f
--- a/cases/create/opt_cases/mic_cr_loop_pack-to-zip_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_pack-to-zip_ia32.case
@@ -6,7 +6,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks \
   --pack-to=@NAME@.zip \
   --logfile=mic.log
@@ -15,7 +15,11 @@ grep 'Zipping files to' mic.log
 grep 'Finished' mic.log
 test -f ./mic-output/handset_blackbay*.zip
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo unzip ./mic-output/handset_blackbay*.zip -d ./mic-output
 test -e ./mic-output/platform.img
 sudo mic chroot ./mic-output/platform.img -c ls
diff --git a/cases/create/opt_cases/mic_cr_loop_pkgmgr-Invalid_ia32.case b/cases/create/opt_cases/mic_cr_loop_pkgmgr-Invalid_ia32.case
old mode 100644
new mode 100755
index e6996ca..3a884d7
--- a/cases/create/opt_cases/mic_cr_loop_pkgmgr-Invalid_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_pkgmgr-Invalid_ia32.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 ! (sudo mic -d -v cr loop handset_blackbay.ks --pkgmgr=None 2>&1 | tee mic.log)
 grep -i "Can't find backend: None" mic.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_pkgmgr-yum_ia32.case b/cases/create/opt_cases/mic_cr_loop_pkgmgr-yum_ia32.case
old mode 100644
new mode 100755
index 01394c2..a893542
--- a/cases/create/opt_cases/mic_cr_loop_pkgmgr-yum_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_pkgmgr-yum_ia32.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 ! (sudo mic -d -v cr loop handset_blackbay.ks --pkgmgr=yum 2>&1 | tee mic.log)
 grep -i "Can't find backend: yum" mic.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_pkgmgr-zypp_ia32.case b/cases/create/opt_cases/mic_cr_loop_pkgmgr-zypp_ia32.case
old mode 100644
new mode 100755
index fbb9990..74653b9
--- a/cases/create/opt_cases/mic_cr_loop_pkgmgr-zypp_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_pkgmgr-zypp_ia32.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --pkgmgr=zypp  --logfile=mic.log
 grep 'Finished' mic.log
 test -f ./mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_record-pkgs-Invalid_ia32.case b/cases/create/opt_cases/mic_cr_loop_record-pkgs-Invalid_ia32.case
old mode 100644
new mode 100755
index d6c5dd7..067eed0
--- a/cases/create/opt_cases/mic_cr_loop_record-pkgs-Invalid_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_record-pkgs-Invalid_ia32.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 ! (sudo mic -d -v cr loop handset_blackbay.ks --record-pkgs=propery  2>&1 | tee mic.log)
 grep -i 'Invalid pkg recording: propery' mic.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_record-pkgs-name-content-license-vcs_ia32.case b/cases/create/opt_cases/mic_cr_loop_record-pkgs-name-content-license-vcs_ia32.case
old mode 100644
new mode 100755
index 2ac906d..46981f5
--- a/cases/create/opt_cases/mic_cr_loop_record-pkgs-name-content-license-vcs_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_record-pkgs-name-content-license-vcs_ia32.case
@@ -6,14 +6,18 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks \
   --record-pkgs=name,content,license,vcs \
   --logfile=mic.log
 grep 'Finished' mic.log
 test -f ./mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 cat ./mic-output/handset_blackbay*.packages | grep bash
 cat ./mic-output/handset_blackbay*.license | grep bash
 cat ./mic-output/handset_blackbay*.files | grep bash
diff --git a/cases/create/opt_cases/mic_cr_loop_release_check_log_completeness.case b/cases/create/opt_cases/mic_cr_loop_release_check_log_completeness.case
old mode 100644
new mode 100755
index dc69ca5..c32d605
--- a/cases/create/opt_cases/mic_cr_loop_release_check_log_completeness.case
+++ b/cases/create/opt_cases/mic_cr_loop_release_check_log_completeness.case
@@ -8,12 +8,16 @@ then test whether image will generate correspondently.</summary>
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic --non-interactive cr loop handset_blackbay.ks --release=tizen-2.2_20130719.3
 grep "Finished" ./mic-output/tizen-2.2_20130719.3/images/handset_blackbay*/tizen-2.2_20130719.3_handset_blackbay.log
 sudo test -f ./mic-output/tizen-2.2_20130719.3/images/handset_blackbay*/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo test -f ./mic-output/tizen-2.2_20130719.3/images/handset_blackbay*/MD5SUMS
 sudo test -f ./mic-output/tizen-2.2_20130719.3/images/handset_blackbay*/tizen-2.2_20130719.3_handset_blackbay.packages
 sudo test -f ./mic-output/tizen-2.2_20130719.3/images/handset_blackbay*/tizen-2.2_20130719.3_handset_blackbay.ks
diff --git a/cases/create/opt_cases/mic_cr_loop_release_ia32.case b/cases/create/opt_cases/mic_cr_loop_release_ia32.case
old mode 100644
new mode 100755
index 0ed454e..a759452
--- a/cases/create/opt_cases/mic_cr_loop_release_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_release_ia32.case
@@ -8,12 +8,16 @@ then test whether image will generate correspondently.</summary>
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic --non-interactive cr loop handset_blackbay.ks --release=tizen-2.2_20130719.3
 grep "Finished" ./mic-output/tizen-2.2_20130719.3/images/handset_blackbay*/tizen-2.2_20130719.3_handset_blackbay.log
 sudo test -f ./mic-output/tizen-2.2_20130719.3/images/handset_blackbay*/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo test -f ./mic-output/tizen-2.2_20130719.3/images/handset_blackbay*/MD5SUMS
 sudo test -f ./mic-output/tizen-2.2_20130719.3/images/handset_blackbay*/tizen-2.2_20130719.3_handset_blackbay.packages
 sudo test -f ./mic-output/tizen-2.2_20130719.3/images/handset_blackbay*/tizen-2.2_20130719.3_handset_blackbay.ks
diff --git a/cases/create/opt_cases/mic_cr_loop_release_latest_ia32.case b/cases/create/opt_cases/mic_cr_loop_release_latest_ia32.case
old mode 100644
new mode 100755
index 6253192..20d9b3f
--- a/cases/create/opt_cases/mic_cr_loop_release_latest_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_release_latest_ia32.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic --non-interactive cr loop handset_blackbay.ks  --release=latest
 grep "Finished" ./mic-output/latest/images/handset_blackbay*/latest_handset_blackbay.log
 sudo test -f ./mic-output/latest/images/handset_blackbay*/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo test -f ./mic-output/latest/images/handset_blackbay*/MD5SUMS
 sudo test -f ./mic-output/latest/images/handset_blackbay*/latest_handset_blackbay.packages
 sudo test -f ./mic-output/latest/images/handset_blackbay*/latest_handset_blackbay.ks
diff --git a/cases/create/opt_cases/mic_cr_loop_release_pack-to.case b/cases/create/opt_cases/mic_cr_loop_release_pack-to.case
index bbd1674..1eeef66 100755
--- a/cases/create/opt_cases/mic_cr_loop_release_pack-to.case
+++ b/cases/create/opt_cases/mic_cr_loop_release_pack-to.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --release SNAPSHOT --pack-to=IMAGENAME.tar.gz
 grep 'Finished' ./mic-output/SNAPSHOT/images/handset_blackbay/IMAGENAME.log
 test -f ./mic-output/SNAPSHOT/images/handset_blackbay/IMAGENAME.tar.gz
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo test -e ./mic-output/SNAPSHOT/images/handset_blackbay/IMAGENAME.xml
 sudo test -e ./mic-output/SNAPSHOT/images/handset_blackbay/IMAGENAME.packages
 sudo test -e ./mic-output/SNAPSHOT/images/handset_blackbay/IMAGENAME.ks
diff --git a/cases/create/opt_cases/mic_cr_loop_repo_ia32.case b/cases/create/opt_cases/mic_cr_loop_repo_ia32.case
index 625b23f..24e54ac 100755
--- a/cases/create/opt_cases/mic_cr_loop_repo_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_repo_ia32.case
@@ -8,19 +8,27 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 # give one repo in command line, another in ks
 sudo mic -d -v cr loop handset_blackbay_test_repo.ks --repo "name=Tizen-main;baseurl=http://10.113.136.109/repo/download.tizen.org/releases/2.2/tizen-2.2_20130719.3/repos/tizen-main/ia32/packages/" --logfile=handset1.log
 grep 'Finished' handset1.log
 test -e mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 # give two repos in command line and ignore ks repo
 sudo mic -d -v cr loop handset_blackbay_test_repo.ks --repo "name=Tizen-main;baseurl=http://10.113.136.109/repo/download.tizen.org/releases/2.2/tizen-2.2_20130719.3/repos/tizen-main/ia32/packages/" --repo "name=Tizen-base;baseurl=http://10.113.136.109/repo/download.tizen.org/releases/2.2/tizen-2.2_20130719.3/repos/tizen-base/ia32/packages/" --logfile=handset2.log --ignore-ksrepo
 grep 'Finished' handset2.log
 # give one repo in command line and one in ks, ignore ks repo
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ! (sudo mic -d -v cr loop handset_blackbay_test_repo.ks --repo "name=Tizen-main;baseurl=http://10.113.136.109/repo/download.tizen.org/releases/2.2/tizen-2.2_20130719.3/repos/tizen-main/ia32/packages/" --logfile=handset3.log --ignore-ksrepo)
 grep -i "Unable to find package" handset3.log
 ]]></steps>
diff --git a/cases/create/opt_cases/mic_cr_loop_runtime-Invalid_ia32.case b/cases/create/opt_cases/mic_cr_loop_runtime-Invalid_ia32.case
old mode 100644
new mode 100755
index 964dcfc..6df9e50
--- a/cases/create/opt_cases/mic_cr_loop_runtime-Invalid_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_runtime-Invalid_ia32.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 ! (sudo mic -d -v cr loop handset_blackbay.ks --runtime=invalid  2>&1 | tee mic.log)
 grep -i "Invalid runtime mode: invalid" mic.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_runtime-bootstrap_ia32.case b/cases/create/opt_cases/mic_cr_loop_runtime-bootstrap_ia32.case
old mode 100644
new mode 100755
index 76ad695..068050c
--- a/cases/create/opt_cases/mic_cr_loop_runtime-bootstrap_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_runtime-bootstrap_ia32.case
@@ -6,7 +6,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks \
   --runtime=bootstrap \
   --logfile=mic.log
@@ -14,7 +14,11 @@ grep 'Start mic in bootstrap' mic.log
 grep 'Finished' mic.log
 test -f ./mic-output/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_loop_shrink_ia32.case b/cases/create/opt_cases/mic_cr_loop_shrink_ia32.case
old mode 100644
new mode 100755
index 9733e38..e5bc654
--- a/cases/create/opt_cases/mic_cr_loop_shrink_ia32.case
+++ b/cases/create/opt_cases/mic_cr_loop_shrink_ia32.case
@@ -7,17 +7,25 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks -o out1 --logfile=mic1.log
 grep 'Finished' mic1.log
 test -f ./out1/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo mic -d -v cr loop handset_blackbay.ks -o out2 --shrink --logfile=mic2.log
 grep 'Finished' mic2.log
 test -f ./out2/platform.img
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 source compute_volume.sh
 p1=`compute_volume ./out1/platform.img`
 p2=`compute_volume ./out2/platform.img`
diff --git a/cases/create/opt_cases/mic_cr_loop_tmpfs.case b/cases/create/opt_cases/mic_cr_loop_tmpfs.case
old mode 100644
new mode 100755
index 098341d..c6cd1d4
--- a/cases/create/opt_cases/mic_cr_loop_tmpfs.case
+++ b/cases/create/opt_cases/mic_cr_loop_tmpfs.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr loop handset_blackbay.ks --tmpfs --logfile=./log/handset.log
 test -f ./log/handset.log
 grep 'Finished' ./log/handset.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_qcow_logfile-current-file_ia32.case b/cases/create/opt_cases/mic_cr_qcow_logfile-current-file_ia32.case
old mode 100644
new mode 100755
index 8eaee7d..737ddd3
--- a/cases/create/opt_cases/mic_cr_qcow_logfile-current-file_ia32.case
+++ b/cases/create/opt_cases/mic_cr_qcow_logfile-current-file_ia32.case
@@ -6,7 +6,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 hostname=$(hostname)
 sudo mic -d -v cr qcow qcow_image.ks --logfile=./log/qcow.log -k /home/build/mic-tmp-cache
 # use '-k /home/build/mic-tmp-cache', because directory '/home/build/' has larger space, if
@@ -18,7 +18,11 @@ file ./mic-output/emulimg-3.0.img | grep -i 'QCOW'
 grep 'Finished' ./log/qcow.log
 grep "$hostname" ./log/qcow.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 egrep 'mic [0-9]{1,2}\.[0-9]+' ./log/qcow.log
 ]]></steps>
   <teardown><![CDATA[
diff --git a/cases/create/opt_cases/mic_cr_raw_compress-image-bz2_ia32.case b/cases/create/opt_cases/mic_cr_raw_compress-image-bz2_ia32.case
index 2c512b5..64547c6 100755
--- a/cases/create/opt_cases/mic_cr_raw_compress-image-bz2_ia32.case
+++ b/cases/create/opt_cases/mic_cr_raw_compress-image-bz2_ia32.case
@@ -7,7 +7,7 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 enforce_path=$(sudo which setenforce || true)
 if [ ! -z $enforce_path ];then
     sudo $enforce_path 0 || true
@@ -15,12 +15,20 @@ fi
 sudo mic -d -v cr raw ivi.ks -o out1 --logfile=mic1.log
 grep 'Finished' mic1.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo mic -d -v cr raw ivi.ks --compress-image=bz2 -o out2  --logfile=mic2.log
 grep 'Finished' mic2.log
 test -f ./out2/ivi*.raw.bz2
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 source compute_volume.sh
 cd out1
 name1=`ls ivi*.raw`
diff --git a/cases/create/opt_cases/mic_cr_raw_compress-image-gz_ia32.case b/cases/create/opt_cases/mic_cr_raw_compress-image-gz_ia32.case
index f8eb73f..a195ea6 100755
--- a/cases/create/opt_cases/mic_cr_raw_compress-image-gz_ia32.case
+++ b/cases/create/opt_cases/mic_cr_raw_compress-image-gz_ia32.case
@@ -7,17 +7,25 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr raw ivi.ks -o out1 --logfile=mic1.log
 grep 'Finished' mic1.log
 test -f ./out1/ivi*.raw
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 sudo mic -d -v cr raw ivi.ks --compress-image=gz -o out2 --logfile=mic2.log
 grep 'Finished' mic2.log
 test -f ./out2/ivi*.raw.gz
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 source compute_volume.sh
 cd out1
 name1=`ls ivi*.raw`
diff --git a/cases/create/opt_cases/mic_cr_raw_compress-image-invalid_ia32.case b/cases/create/opt_cases/mic_cr_raw_compress-image-invalid_ia32.case
index 352809d..cfe1c77 100755
--- a/cases/create/opt_cases/mic_cr_raw_compress-image-invalid_ia32.case
+++ b/cases/create/opt_cases/mic_cr_raw_compress-image-invalid_ia32.case
@@ -6,11 +6,15 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 ! (sudo mic -d -v cr raw ivi.ks --compress-image=zip 2>&1 | tee mic2.log )
 grep  "compress-image: invalid choice: 'zip'" mic2.log
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 ]]></steps>
   <teardown><![CDATA[
 echo "cleaning..."
diff --git a/cases/create/opt_cases/mic_cr_raw_fstab-entry-name.case b/cases/create/opt_cases/mic_cr_raw_fstab-entry-name.case
index 22b81ff..c131ee4 100755
--- a/cases/create/opt_cases/mic_cr_raw_fstab-entry-name.case
+++ b/cases/create/opt_cases/mic_cr_raw_fstab-entry-name.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr raw  ivi.ks --fstab-entry=name --logfile=log.file
 grep "Finished" log.file
 ls mic-output/ | grep 'ivi-.*-sdb.raw'
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 raw_image=$(ls mic-output/ivi-*-sdb.raw)
 sudo mkdir -p mic-output/ivi_dir/boot
 kpartx_path=$(sudo which kpartx)
diff --git a/cases/create/opt_cases/mic_cr_raw_fstab-entry-uuid.case b/cases/create/opt_cases/mic_cr_raw_fstab-entry-uuid.case
index cf57a77..6590d2b 100755
--- a/cases/create/opt_cases/mic_cr_raw_fstab-entry-uuid.case
+++ b/cases/create/opt_cases/mic_cr_raw_fstab-entry-uuid.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr raw ivi.ks --fstab-entry=uuid --logfile=log.file
 grep "Finished" log.file
 ls mic-output/ | grep 'ivi-.*-sdb.raw'
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 raw_image=$(ls mic-output/ivi-*-sdb.raw)
 sudo mkdir -p mic-output/ivi_dir/boot
 kpartx_path=$(sudo which kpartx)
diff --git a/cases/create/opt_cases/mic_cr_raw_generate-bmap_ia32.case b/cases/create/opt_cases/mic_cr_raw_generate-bmap_ia32.case
index f36c721..724a129 100755
--- a/cases/create/opt_cases/mic_cr_raw_generate-bmap_ia32.case
+++ b/cases/create/opt_cases/mic_cr_raw_generate-bmap_ia32.case
@@ -6,12 +6,16 @@
   <steps><![CDATA[
 losetup_path=$(sudo which losetup)
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_before=$(sudo $losetup_path -a | wc -l)
 sudo mic -d -v cr raw ivi.ks --generate-bmap --logfile=mic1.log
 grep 'Finished' mic1.log
 test -f ./mic-output/ivi*.raw
 sudo $losetup_path -a
-sudo $losetup_path -a | wc -l | xargs test 0 -eq
+loop_used_after=$(sudo $losetup_path -a | wc -l)
+if [ "$loop_used_before" -ne "$loop_used_after" ];then
+    echo "Number of loop devices is not the same with previous number."
+    exit 1
+fi
 test -f ./mic-output/ivi*.bmap
 ]]></steps>
   <teardown><![CDATA[