Re: [PATCH v3] x86/cpu: Fix x86_match_cpu() to match just X86_VENDOR_INTEL

[Borislav Petkov]

On Fri, May 17, 2024 at 10:21:34AM -0700, Tony Luck wrote:
> diff --git a/arch/x86/kernel/cpu/match.c b/arch/x86/kernel/cpu/match.c
> index 8651643bddae..996f96cfce68 100644
> --- a/arch/x86/kernel/cpu/match.c
> +++ b/arch/x86/kernel/cpu/match.c
> @@ -39,7 +39,7 @@ const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match)
>  	struct cpuinfo_x86 *c = &boot_cpu_data;
>  
>  	for (m = match;
> -	     m->vendor | m->family | m->model | m->steppings | m->feature;
> +	     m->vendor | m->family | m->model | m->steppings | m->feature | m->flags;

I think this should not do anything implicit even if it is correct but
should explicitly check

	if (!(m->flags & X86_CPU_ID_FLAG_VENDOR_VALID))
		continue;

I don't have a clear idea how exactly yet - I need to play with it.

Maybe this stupid flow in the loop should be finally fixed into
something more readable and sensible...

Thx.

-- 
Regards/Gruss,
    Boris.

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