Re: [PATCH v4 03/16] x86/alternatives: Disable LASS when patching kernel alternatives

[Borislav Petkov]

On Wed, Jul 10, 2024 at 07:06:39PM +0300, Alexander Shishkin wrote:
>  static void text_poke_memcpy(void *dst, const void *src, size_t len)
>  {
> -	memcpy(dst, src, len);
> +	stac();
> +	__inline_memcpy(dst, src, len);
> +	clac();

I think you need LASS-specific stac()/clac() or an alternative_2 or so. You
can't cause that perf penalty on !LASS machines.

-- 
Regards/Gruss,
    Boris.

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