ACK: [SRU][Trusty][PATCH 1/1] UBUNTU: SAUCE: x86: Use barrier_nospec in arch/x86/um/asm/barrier.h

[Kleber Souza]

On 07/27/18 14:49, Juerg Haefliger wrote:
> BugLink: https://bugs.launchpad.net/bugs/1774181
> 
> Modify the duplicate rdtsc_barrier() in arch/x86/um/asm/barrier.h.
> 
> Fixes: b3d7ad85b80b ("x86: Introduce barrier_nospec")
> Signed-off-by: Juerg Haefliger <juergh at canonical.com>

Acked-by: Kleber Sacilotto de Souza <kleber.souza at canonical.com>

> ---
>  arch/x86/um/asm/barrier.h | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/arch/x86/um/asm/barrier.h b/arch/x86/um/asm/barrier.h
> index 7d01b8c56c00..f16760f3d848 100644
> --- a/arch/x86/um/asm/barrier.h
> +++ b/arch/x86/um/asm/barrier.h
> @@ -68,8 +68,7 @@
>   */
>  static inline void rdtsc_barrier(void)
>  {
> -	alternative(ASM_NOP3, "mfence", X86_FEATURE_MFENCE_RDTSC);
> -	alternative(ASM_NOP3, "lfence", X86_FEATURE_LFENCE_RDTSC);
> +	barrier_nospec();
>  }
>  
>  #endif
>