Re: [PATCHv10 05/18] x86/kexec: Keep CR4.MCE set during kexec for TDX guest
From: Borislav Petkov
Date: Mon Apr 29 2024 - 10:47:30 EST
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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