| Message ID | 1516923320-16959-16-git-send-email-mst@redhat.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | ptr_ring fixes | expand |
On 2018年01月26日 07:36, Michael S. Tsirkin wrote: > Offset 128 overlaps the last word of the redzone. > Use 132 which is always beyond that. > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> > --- > tools/virtio/ringtest/main.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/tools/virtio/ringtest/main.h b/tools/virtio/ringtest/main.h > index 593a328..301d59b 100644 > --- a/tools/virtio/ringtest/main.h > +++ b/tools/virtio/ringtest/main.h > @@ -111,7 +111,7 @@ static inline void busy_wait(void) > } > > #if defined(__x86_64__) || defined(__i386__) > -#define smp_mb() asm volatile("lock; addl $0,-128(%%rsp)" ::: "memory", "cc") Just wonder did "rsp" work for __i386__ ? Thanks > +#define smp_mb() asm volatile("lock; addl $0,-132(%%rsp)" ::: "memory", "cc") > #else > /* > * Not using __ATOMIC_SEQ_CST since gcc docs say they are only synchronized
On Fri, Jan 26, 2018 at 11:56:14AM +0800, Jason Wang wrote: > > > On 2018年01月26日 07:36, Michael S. Tsirkin wrote: > > Offset 128 overlaps the last word of the redzone. > > Use 132 which is always beyond that. > > > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> > > --- > > tools/virtio/ringtest/main.h | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/tools/virtio/ringtest/main.h b/tools/virtio/ringtest/main.h > > index 593a328..301d59b 100644 > > --- a/tools/virtio/ringtest/main.h > > +++ b/tools/virtio/ringtest/main.h > > @@ -111,7 +111,7 @@ static inline void busy_wait(void) > > } > > #if defined(__x86_64__) || defined(__i386__) > > -#define smp_mb() asm volatile("lock; addl $0,-128(%%rsp)" ::: "memory", "cc") > > Just wonder did "rsp" work for __i386__ ? > > Thanks Oh you are right of course. Probably no one ever run this one on i386 :) I'll add a patch on top as this is not a new bug. > > +#define smp_mb() asm volatile("lock; addl $0,-132(%%rsp)" ::: "memory", "cc") > > #else > > /* > > * Not using __ATOMIC_SEQ_CST since gcc docs say they are only synchronized
diff --git a/tools/virtio/ringtest/main.h b/tools/virtio/ringtest/main.h index 593a328..301d59b 100644 --- a/tools/virtio/ringtest/main.h +++ b/tools/virtio/ringtest/main.h @@ -111,7 +111,7 @@ static inline void busy_wait(void) } #if defined(__x86_64__) || defined(__i386__) -#define smp_mb() asm volatile("lock; addl $0,-128(%%rsp)" ::: "memory", "cc") +#define smp_mb() asm volatile("lock; addl $0,-132(%%rsp)" ::: "memory", "cc") #else /* * Not using __ATOMIC_SEQ_CST since gcc docs say they are only synchronized
Offset 128 overlaps the last word of the redzone. Use 132 which is always beyond that. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> --- tools/virtio/ringtest/main.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)