Re: [PATCH] x86/CPU/AMD: Ignore invalid reset reason value

[Borislav Petkov]

On Mon, Jul 21, 2025 at 06:11:54PM +0000, Yazen Ghannam wrote:
> The reset reason value may be "all bits set", e.g. 0xFFFFFFFF. This is a
> commonly used error response from hardware. This may occur due to a real
> hardware issue or when running in a VM.

Well, which is it Libing is reporting? VM or a real hw issue?

If it is a VM, is that -1 the only thing a VMM returns when reading that
MMIO address or can it be anything?

If latter, you need to check X86_FEATURE_HYPERVISOR.

Same for a real hw issue.

IOW, is -1 the *only* invalid data we can read here or are we playing
whack-a-mole with it?

Thx.

-- 
Regards/Gruss,
    Boris.

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