Re: [PATCH] x86/microcode: Fix crashes on early 486 CPUs due to usage of 'cpuid'.

[Borislav Petkov]

On Sat, Apr 05, 2025 at 01:33:46PM -0700, H. Peter Anvin wrote:
> How the Hades does c->x86 not get set to 4 (hence < 0x10) on this CPU?
> 
> That's the real bug imo...

Go to the first mail in the thread.

4c585af7180c ("x86/boot/32: Temporarily map initrd for microcode loading")

walks straight into  native_cpuid_ecx().

Which reminds me - I should remove that have_cpuid_p() in load_ucode_bsp() now
too and move the disabled check up.

-- 
Regards/Gruss,
    Boris.

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