Re: [PATCH] vhost: disable metadata prefetch optimization

[Jason Wang <jasowang@redhat.com>]

On 2019/7/26 下午7:51, Michael S. Tsirkin wrote:
> This seems to cause guest and host memory corruption.
> Disable for now until we get a better handle on that.
>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
>
> I put this in linux-next, we'll re-enable if we can fix
> the outstanding issues in a short order.


Btw, is this more suitable to e.g revert the 
842aa64eddacd23adc6ecdbc69cb2030bec47122 and let syzbot fuzz more on the 
current code?

I think we won't accept that patch eventually, so I suspect what syzbot 
reports today is a false positives.

Thanks


>
>   drivers/vhost/vhost.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
> index 819296332913..42a8c2a13ab1 100644
> --- a/drivers/vhost/vhost.h
> +++ b/drivers/vhost/vhost.h
> @@ -96,7 +96,7 @@ struct vhost_uaddr {
>   };
>   
>   #if defined(CONFIG_MMU_NOTIFIER) && ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0
> -#define VHOST_ARCH_CAN_ACCEL_UACCESS 1
> +#define VHOST_ARCH_CAN_ACCEL_UACCESS 0
>   #else
>   #define VHOST_ARCH_CAN_ACCEL_UACCESS 0
>   #endif