lkml.org 
[lkml]   [2022]   [Jan]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v8 20/40] x86/sev: Use SEV-SNP AP creation to start secondary CPUs
From
Date
On 1/12/22 10:33 AM, Brijesh Singh wrote:
> On 12/31/21 9:36 AM, Borislav Petkov wrote:
>> On Fri, Dec 10, 2021 at 09:43:12AM -0600, Brijesh Singh wrote:

>>> +     * an attempt was done to use the current VMSA with a running vCPU, a
>>> +     * #VMEXIT of that vCPU would wipe out all of the settings being done
>>> +     * here.
>>
>> I don't understand - this is waking up a CPU, how can it ever be a
>> running vCPU which is using the current VMSA?!

Yes, in general. My thought was that nothing is stopping a malicious
hypervisor from performing a VMRUN on that vCPU and then the VMSA would be
in use.

Thanks,
Tom

>>
>> There is per_cpu(snp_vmsa, cpu), who else can be using that one currently?
>>
>
> Maybe Tom can expand it bit more?
>

\
 
 \ /
  Last update: 2022-01-12 18:10    [W:0.137 / U:0.092 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site