Re: [PATCH v2 02/11] KVM: SVM: Don't BUG if userspace injects a soft interrupt with GIF=0

From: Maciej S. Szmigiero
Date: Thu Apr 28 2022 - 09:27:28 EST

On 28.04.2022 09:35, Maxim Levitsky wrote:
On Sat, 2022-04-23 at 02:14 +0000, Sean Christopherson wrote:
From: Maciej S. Szmigiero <maciej.szmigiero@xxxxxxxxxx>

Don't BUG/WARN on interrupt injection due to GIF being cleared if the
injected event is a soft interrupt, which are not actually IRQs and thus

Are any injected events subject to GIF set? I think that EVENTINJ just injects
unconditionaly whatever hypervisor puts in it.

That's right, EVENTINJ will pretty much always inject, even when the CPU
is in a 'wrong' state (like for example, injecting a hardware interrupt
or a NMI with GIF masked).

But KVM as a L0 is not supposed to inject a hardware interrupt into guest
with GIF unset since the guest is obviously not expecting it then.
Hence this WARN_ON().

Best regards,
Maxim Levitsky