Re: [PATCH v7 013/120] x86/cpu: Use parsed CPUID(0x80000000)

[Borislav Petkov]

On Tue, Jun 02, 2026 at 03:28:36PM +0200, Ahmed S. Darwish wrote:
> He is correct.

So I went forward to look a bit... the whole point of that code in
microcode_check() is to rescan the *full* CPUID leafage into a separate copy
of cpuinfo_x86.cpuid.

And then compare the old and the new one and see whether microcode changed
anything.

I see you're doing something in patch 106 and I'll know much better when I get
to it but my gut feeling right now tells me, you should leave that code alone
and do it separately, ontop, when we start removing ->x86_capability.

AFAICT, the CPUID parser can simply do:

        struct cpuid_table *table = &second_copy.cpuid;
        
        cpuid_fill_table(table, cpuid_parse_entries, nr_entries);

and fill the table. Then we'll need to go over that table and compare it with
the existing one. I guess adding a __cmp_range() or so in the same manner like
you do iterate over ranges right now.

Something along those lines I guess...

Thx.

-- 
Regards/Gruss,
    Boris.

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