powerpc: disable KASAN instrumentation on early/critical files.
authorChristophe Leroy <christophe.leroy@c-s.fr>
Fri, 26 Apr 2019 16:23:33 +0000 (16:23 +0000)
committerMichael Ellerman <mpe@ellerman.id.au>
Thu, 2 May 2019 15:20:26 +0000 (01:20 +1000)
All files containing functions run before kasan_early_init() is called
must have KASAN instrumentation disabled.

For those file, branch profiling also have to be disabled otherwise
each if () generates a call to ftrace_likely_update().

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/kernel/Makefile
arch/powerpc/lib/Makefile
arch/powerpc/mm/Makefile
arch/powerpc/platforms/powermac/Makefile
arch/powerpc/purgatory/Makefile
arch/powerpc/xmon/Makefile

index 45e4775..0ea6c4a 100644 (file)
@@ -31,6 +31,18 @@ CFLAGS_REMOVE_btext.o = $(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_prom.o = $(CC_FLAGS_FTRACE)
 endif
 
+KASAN_SANITIZE_early_32.o := n
+KASAN_SANITIZE_cputable.o := n
+KASAN_SANITIZE_prom_init.o := n
+KASAN_SANITIZE_btext.o := n
+
+ifdef CONFIG_KASAN
+CFLAGS_early_32.o += -DDISABLE_BRANCH_PROFILING
+CFLAGS_cputable.o += -DDISABLE_BRANCH_PROFILING
+CFLAGS_prom_init.o += -DDISABLE_BRANCH_PROFILING
+CFLAGS_btext.o += -DDISABLE_BRANCH_PROFILING
+endif
+
 obj-y                          := cputable.o ptrace.o syscalls.o \
                                   irq.o align.o signal_32.o pmc.o vdso.o \
                                   process.o systbl.o idle.o \
index 47a4de4..c55f9c2 100644 (file)
@@ -8,6 +8,14 @@ ccflags-$(CONFIG_PPC64)        := $(NO_MINIMAL_TOC)
 CFLAGS_REMOVE_code-patching.o = $(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_feature-fixups.o = $(CC_FLAGS_FTRACE)
 
+KASAN_SANITIZE_code-patching.o := n
+KASAN_SANITIZE_feature-fixups.o := n
+
+ifdef CONFIG_KASAN
+CFLAGS_code-patching.o += -DDISABLE_BRANCH_PROFILING
+CFLAGS_feature-fixups.o += -DDISABLE_BRANCH_PROFILING
+endif
+
 obj-y += alloc.o code-patching.o feature-fixups.o
 
 ifndef CONFIG_KASAN
index c7d5f37..62735f3 100644 (file)
@@ -5,6 +5,12 @@
 
 ccflags-$(CONFIG_PPC64)        := $(NO_MINIMAL_TOC)
 
+KASAN_SANITIZE_ppc_mmu_32.o := n
+
+ifdef CONFIG_KASAN
+CFLAGS_ppc_mmu_32.o            += -DDISABLE_BRANCH_PROFILING
+endif
+
 obj-y                          := fault.o mem.o pgtable.o mmap.o \
                                   init_$(BITS).o pgtable_$(BITS).o \
                                   pgtable-frag.o \
index 20ebf35..f4247ad 100644 (file)
@@ -2,6 +2,12 @@
 CFLAGS_bootx_init.o            += -fPIC
 CFLAGS_bootx_init.o            += $(call cc-option, -fno-stack-protector)
 
+KASAN_SANITIZE_bootx_init.o := n
+
+ifdef CONFIG_KASAN
+CFLAGS_bootx_init.o            += -DDISABLE_BRANCH_PROFILING
+endif
+
 ifdef CONFIG_FUNCTION_TRACER
 # Do not trace early boot code
 CFLAGS_REMOVE_bootx_init.o = $(CC_FLAGS_FTRACE)
index 4314ba5..7c6d8b1 100644 (file)
@@ -1,4 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
+
+KASAN_SANITIZE := n
+
 targets += trampoline.o purgatory.ro kexec-purgatory.c
 
 LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined
index 3050f93..f142570 100644 (file)
@@ -7,6 +7,7 @@ subdir-ccflags-y := $(call cc-disable-warning, builtin-requires-header)
 GCOV_PROFILE := n
 KCOV_INSTRUMENT := n
 UBSAN_SANITIZE := n
+KASAN_SANITIZE := n
 
 # Disable ftrace for the entire directory
 ORIG_CFLAGS := $(KBUILD_CFLAGS)