[PATCH v2] x86/kexec: Add EFI config table identity mapping for kexec kernel

[Borislav Petkov]

On Fri, Jul 07, 2023 at 10:22:56AM +0200, Joerg Roedel wrote:
> On Fri, Jul 07, 2023 at 12:23:59PM +0800, Baoquan He wrote:
> > I am wondering why we don't detect the cpu type and return early inside
> > sev_enable() if it's Intel cpu.
> > 
> > We can't rely on CONFIG_AMD_MEM_ENCRYPT to decide if the code need be
> > executed or not because we usually enable them all in distros.
> 
> Looking at the code in head_64.S, by the time sev_enable() runs the SEV
> bit should already be set in sev_status. Maybe use that to detect
> whether SEV is enabled and bail out early?

There was something about getting the CPUID page on SNP *before*
actually calling CPUID but this is not the first time we had trouble in
this area. This needs to be done differently.

Michael?

-- 
Regards/Gruss,
    Boris.

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