platform/x86/intel/ifs: release cpus_read_lock()

Couple of error paths in do_core_test() was returning directly without
doing a necessary cpus_read_unlock().

Following lockdep warning was observed when exercising these scenarios
with PROVE_RAW_LOCK_NESTING enabled:

[  139.304775] ================================================
[  139.311185] WARNING: lock held when returning to user space!
[  139.317593] 6.6.0-rc2ifs01+ #11 Tainted: G S      W I
[  139.324499] ------------------------------------------------
[  139.330908] bash/11476 is leaving the kernel with locks still held!
[  139.338000] 1 lock held by bash/11476:
[  139.342262]  #0: ffffffffaa26c930 (cpu_hotplug_lock){++++}-{0:0}, at:
do_core_test+0x35/0x1c0 [intel_ifs]

Fix the flow so that all scenarios release the lock prior to returning
from the function.

Fixes: 5210fb4e1880 ("platform/x86/intel/ifs: Sysfs interface for Array BIST")
Cc: stable@vger.kernel.org
Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Link: https://lore.kernel.org/r/20230927184824.2566086-1-jithu.joseph@intel.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

diff --git a/drivers/platform/x86/intel/ifs/runtest.c b/drivers/platform/x86/intel/ifs/runtest.c
index 1061eb7..43c864a 100644 (file)
--- a/drivers/platform/x86/intel/ifs/runtest.c
+++ b/drivers/platform/x86/intel/ifs/runtest.c
@@ -331,14 +331,15 @@ int do_core_test(int cpu, struct device *dev)
        switch (test->test_num) {
        case IFS_TYPE_SAF:
                if (!ifsd->loaded)
-                       return -EPERM;
-               ifs_test_core(cpu, dev);
+                       ret = -EPERM;
+               else
+                       ifs_test_core(cpu, dev);
                break;
        case IFS_TYPE_ARRAY_BIST:
                ifs_array_test_core(cpu, dev);
                break;
        default:
-               return -EINVAL;
+               ret = -EINVAL;
        }
 out:
        cpus_read_unlock();