Re: [PATCH v4 1/8] x86/bugs: Use VM_CLEAR_CPU_BUFFERS in VMX as well

From: Borislav Petkov

Date: Fri Nov 07 2025 - 14:00:04 EST


On Thu, Oct 30, 2025 at 05:30:33PM -0700, Sean Christopherson wrote:
> From: Pawan Gupta <pawan.kumar.gupta@xxxxxxxxxxxxxxx>
>
> TSA mitigation:
>
> d8010d4ba43e ("x86/bugs: Add a Transient Scheduler Attacks mitigation")
>
> introduced VM_CLEAR_CPU_BUFFERS for guests on AMD CPUs. Currently on Intel
> CLEAR_CPU_BUFFERS is being used for guests which has a much broader scope
> (kernel->user also).
>
> Make mitigations on Intel consistent with TSA. This would help handling the

"consistent" as in "use the VM-specific buffer clearing variant in VMX too"?

In any case:

Acked-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>

--
Regards/Gruss,
Boris.

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