Re: [PATCH v9 09/18] x86/sev: Initialize VGIF for secondary VCPUs for Secure AVIC

[Borislav Petkov]

On Mon, Aug 25, 2025 at 11:55:44AM +0530, Upadhyay, Neeraj wrote:
> Ok. Below is the updated description:
> 
> Virtual GIF (VGIF) providing masking capability for when virtual interrupts
> (virtual maskable interrupts, virtual NMIs) can be taken by the guest vCPU.
> Secure AVIC hardware reads VGIF state from the vCPU's VMSA. So, set VGIF for
> secondary CPUs (the configuration for boot CPU is done by the hypervisor),
> to unmask delivery of virtual interrupts  to the vCPU.

Yap.

> I also don't see an explicit mention. I will check on documenting it in the
> APM. However, there are references to virtual interrupts (V_NMI, V_INTR)
> (which requires VGIF support)

Oh, I don't doubt that SAVIC requires VGIF - I just spotted a documentation
hole here so let's start the process of documenting this internally.

-- 
Regards/Gruss,
    Boris.

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