| Message ID | 20220523020051.141460-3-wangkefeng.wang@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64: Fix kcsan test_barrier fail and panic | expand |
On Mon, 23 May 2022 at 03:50, Kefeng Wang <wangkefeng.wang@huawei.com> wrote: > > As "kcsan: Support detecting a subset of missing memory barriers"[1] > introduced KCSAN_STRICT/KCSAN_WEAK_MEMORY which make kcsan detects > more missing memory barrier, but arm64 don't have KCSAN instrumentation > for barriers, so the new selftest test_barrier() and test cases for > memory barrier instrumentation in kcsan_test module will fail, even > panic on selftest. > > Let's prefix all barriers with __ on arm64, as asm-generic/barriers.h > defined the final instrumented version of these barriers, which will > fix the above issues. > > Note, barrier instrumentation can be disabled via __no_kcsan with > appropriate compiler-support (and not just with objtool help), see > commit bd3d5bd1a0ad ("kcsan: Support WEAK_MEMORY with Clang where > no objtool support exists"), it adds disable_sanitizer_instrumentation > to __no_kcsan attribute for Clang which will remove all sanitizer > instrumentation fully (with Clang 14.0). Meanwhile, GCC does the > same thing with no_sanitize. > > [1] https://lore.kernel.org/linux-mm/20211130114433.2580590-1-elver@google.com/ > Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Acked-by: Marco Elver <elver@google.com> > --- > arch/arm64/include/asm/barrier.h | 12 ++++++------ > 1 file changed, 6 insertions(+), 6 deletions(-) > > diff --git a/arch/arm64/include/asm/barrier.h b/arch/arm64/include/asm/barrier.h > index 9f3e2c3d2ca0..2cfc4245d2e2 100644 > --- a/arch/arm64/include/asm/barrier.h > +++ b/arch/arm64/include/asm/barrier.h > @@ -50,13 +50,13 @@ > #define pmr_sync() do {} while (0) > #endif > > -#define mb() dsb(sy) > -#define rmb() dsb(ld) > -#define wmb() dsb(st) > +#define __mb() dsb(sy) > +#define __rmb() dsb(ld) > +#define __wmb() dsb(st) > > -#define dma_mb() dmb(osh) > -#define dma_rmb() dmb(oshld) > -#define dma_wmb() dmb(oshst) > +#define __dma_mb() dmb(osh) > +#define __dma_rmb() dmb(oshld) > +#define __dma_wmb() dmb(oshst) > > #define io_stop_wc() dgh() > > -- > 2.35.3 >
diff --git a/arch/arm64/include/asm/barrier.h b/arch/arm64/include/asm/barrier.h index 9f3e2c3d2ca0..2cfc4245d2e2 100644 --- a/arch/arm64/include/asm/barrier.h +++ b/arch/arm64/include/asm/barrier.h @@ -50,13 +50,13 @@ #define pmr_sync() do {} while (0) #endif -#define mb() dsb(sy) -#define rmb() dsb(ld) -#define wmb() dsb(st) +#define __mb() dsb(sy) +#define __rmb() dsb(ld) +#define __wmb() dsb(st) -#define dma_mb() dmb(osh) -#define dma_rmb() dmb(oshld) -#define dma_wmb() dmb(oshst) +#define __dma_mb() dmb(osh) +#define __dma_rmb() dmb(oshld) +#define __dma_wmb() dmb(oshst) #define io_stop_wc() dgh()
As "kcsan: Support detecting a subset of missing memory barriers"[1] introduced KCSAN_STRICT/KCSAN_WEAK_MEMORY which make kcsan detects more missing memory barrier, but arm64 don't have KCSAN instrumentation for barriers, so the new selftest test_barrier() and test cases for memory barrier instrumentation in kcsan_test module will fail, even panic on selftest. Let's prefix all barriers with __ on arm64, as asm-generic/barriers.h defined the final instrumented version of these barriers, which will fix the above issues. Note, barrier instrumentation can be disabled via __no_kcsan with appropriate compiler-support (and not just with objtool help), see commit bd3d5bd1a0ad ("kcsan: Support WEAK_MEMORY with Clang where no objtool support exists"), it adds disable_sanitizer_instrumentation to __no_kcsan attribute for Clang which will remove all sanitizer instrumentation fully (with Clang 14.0). Meanwhile, GCC does the same thing with no_sanitize. [1] https://lore.kernel.org/linux-mm/20211130114433.2580590-1-elver@google.com/ Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> --- arch/arm64/include/asm/barrier.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)