lkml.org 
[lkml]   [2023]   [May]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH] powerpc/kcsan: Properly instrument arch_spin_unlock()
On Mon, 29 May 2023 at 17:50, Christophe Leroy
<christophe.leroy@csgroup.eu> wrote:
>
> The following boottime error is encountered with SMP kernel:
>
> kcsan: improperly instrumented type=(0): arch_spin_unlock(&arch_spinlock)
> kcsan: improperly instrumented type=(0): spin_unlock(&test_spinlock)
> kcsan: improperly instrumented type=(KCSAN_ACCESS_WRITE): arch_spin_unlock(&arch_spinlock)
> kcsan: improperly instrumented type=(KCSAN_ACCESS_WRITE): spin_unlock(&test_spinlock)
> kcsan: improperly instrumented type=(KCSAN_ACCESS_WRITE | KCSAN_ACCESS_COMPOUND): arch_spin_unlock(&arch_spinlock)
> kcsan: improperly instrumented type=(KCSAN_ACCESS_WRITE | KCSAN_ACCESS_COMPOUND): spin_unlock(&test_spinlock)
> kcsan: selftest: test_barrier failed
> kcsan: selftest: 2/3 tests passed
> Kernel panic - not syncing: selftests failed
>
> Properly instrument arch_spin_unlock() with kcsan_mb().
>
> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>

Acked-by: Marco Elver <elver@google.com>

> ---
> arch/powerpc/include/asm/simple_spinlock.h | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/arch/powerpc/include/asm/simple_spinlock.h b/arch/powerpc/include/asm/simple_spinlock.h
> index 9dcc7e9993b9..4dd12dcb9ef8 100644
> --- a/arch/powerpc/include/asm/simple_spinlock.h
> +++ b/arch/powerpc/include/asm/simple_spinlock.h
> @@ -15,6 +15,7 @@
> * (the type definitions are in asm/simple_spinlock_types.h)
> */
> #include <linux/irqflags.h>
> +#include <linux/kcsan-checks.h>
> #include <asm/paravirt.h>
> #include <asm/paca.h>
> #include <asm/synch.h>
> @@ -126,6 +127,7 @@ static inline void arch_spin_lock(arch_spinlock_t *lock)
>
> static inline void arch_spin_unlock(arch_spinlock_t *lock)
> {
> + kcsan_mb();
> __asm__ __volatile__("# arch_spin_unlock\n\t"
> PPC_RELEASE_BARRIER: : :"memory");
> lock->slock = 0;
> --
> 2.40.1
>

\
 
 \ /
  Last update: 2023-05-30 09:43    [W:0.074 / U:0.060 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site