Re: [PATCH v2 1/2] x86/cpu: Disable CR pinning during CPU bringup

[Dave Hansen]

On 3/12/26 07:53, Nikunj A. Dadhania wrote:
>> The simplest fix is to disable FRED on those kernels, fwiw.
> That would work, but disabling FRED means LTS users will not be able to use 
> FRED with confidential computing—that's not really a fix.

Why not?

Is there something out there that *NEEDS* FRED to function?

> This isn't just SEV-SNP. Xin Li confirmed Intel TDX has the same issue: FRED
> is enabled before exception handling is ready, and #VC/#VE can't be handled on
> secondary CPUs.
> 
> The initialization order is wrong for both SEV-SNP and TDX. The fixes are small
> and targeted—just ensuring FRED state is set up before it's needed.

Sure, it's a theoretical problem for TDX and a practical, demonstrable
one for SEV-SNP.