[PATCH] arm64: Enable KCSAN

Kefeng Wang
2021-11-26T07:51:36Z

This patch enables KCSAN for arm64, with updates to build rules
to not use KCSAN for several incompatible compilation units.

Tested selftest and kcsan_test, and all passed.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
Tested on Qemu with clang 13, based on 5.16-rc2.

[ 0.221518] kcsan: enabled early
[ 0.222422] kcsan: strict mode configured
...
[ 5.839223] kcsan: selftest: 3/3 tests passed
...
[ 517.895102] # kcsan: pass:24 fail:0 skip:0 total:24
[ 517.896393] # Totals: pass:168 fail:0 skip:0 total:168
[ 517.897502] ok 1 - kcsan

arch/arm64/Kconfig | 1 +
arch/arm64/kernel/vdso/Makefile | 1 +
arch/arm64/kvm/hyp/nvhe/Makefile | 1 +
3 files changed, 3 insertions(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 4ff73299f8a9..0ac90875f71d 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -150,6 +150,7 @@ config ARM64
select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
select HAVE_ARCH_KASAN_HW_TAGS if (HAVE_ARCH_KASAN && ARM64_MTE)
+ select HAVE_ARCH_KCSAN
select HAVE_ARCH_KFENCE
select HAVE_ARCH_KGDB
select HAVE_ARCH_MMAP_RND_BITS
diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
index 700767dfd221..60813497a381 100644
--- a/arch/arm64/kernel/vdso/Makefile
+++ b/arch/arm64/kernel/vdso/Makefile
@@ -32,6 +32,7 @@ ccflags-y += -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO
CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) $(GCC_PLUGINS_CFLAGS) \
$(CC_FLAGS_LTO)
KASAN_SANITIZE := n
+KCSAN_SANITIZE := n
UBSAN_SANITIZE := n
OBJECT_FILES_NON_STANDARD := y
KCOV_INSTRUMENT := n
diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile
index c3c11974fa3b..24b2c2425b38 100644
--- a/arch/arm64/kvm/hyp/nvhe/Makefile
+++ b/arch/arm64/kvm/hyp/nvhe/Makefile
@@ -89,6 +89,7 @@ KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) $(CC_FLAGS_CFI)
# cause crashes. Just disable it.
GCOV_PROFILE := n
KASAN_SANITIZE := n
+KCSAN_SANITIZE := n
UBSAN_SANITIZE := n
KCOV_INSTRUMENT := n

--
2.26.2