[PATCHv10 05/18] x86/kexec: Keep CR4.MCE set during kexec for TDX guest

[Borislav Petkov]

On Mon, Apr 29, 2024 at 04:17:38PM +0300, Kirill A. Shutemov wrote:
> As I mentioned above, clearing CR4.MCE triggers #VE. It is quirk of the
> platform.

You mean when identity_mapped() runs as part of a kexec-ed kernel, it
might clear CR4.MCE and that would trigger the #VE?

So, if that is correct, you basically want to *preserve* the CR4.MCE
setting across kexec?

But then __mcheck_cpu_init_generic() will go and set it
unconditionally.

So what exactly is the correct flow here?

Thx.

-- 
Regards/Gruss,
    Boris.

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