Re: [PATCH 7/7] KVM: SVM: Enable save/restore of FRED MSRs
From: Nikunj A. Dadhania
Date: Thu Aug 13 2026 - 23:07:54 EST
On 8/14/2026 5:17 AM, Sean Christopherson wrote:
> On Thu, Aug 13, 2026, Nikunj A. Dadhania wrote:
>> On 8/13/2026 4:57 AM, Sean Christopherson wrote:
>>> On Mon, Aug 10, 2026, Shivansh Dhiman wrote:
>>>> Would you prefer it handled in svm_recalc_fred_msr_intercepts() instead
>>>> while setting intercepts? Or is there a better way to deal with this?
>>>
>>> Take a hard dependency on an upcoming APM update that states the control area
>>> is valid after shutdown, and rework KVM to not clobber control fields on shutdown
>>> interception.
>>
>> AMD APM 3.45 [1] is now publicly available and has the updated wording:
>>
>> "After an intercepted shutdown, the VMCB control area is valid (with
>> the exception of offsets 60h, 61h, and 68h) and the VMCB state save
>> area is undefined."
>
> Very tangential side topic: are combined versions (all five volumes in one PDF)
> of the APM available? Having to open five different PDFs to find information
> is a pain in the rear, especially since I can never remember what's in which
> volume. I can manually splice the PDFs together, but that's far from ideal.
Yes, combined version (Vol 1-5) is available here:
https://docs.amd.com/v/u/en-US/40332_4.10_APM_Vol1-5
Regards,
Nikunj