linux-kernel - Re: [RFC PATCH 2/3] KVM: SVM: Fix IRQ window inhibit handling across multiple vCPUs

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Message-ID: <aXPSOMClTeRKG0_V@google.com>
Date: Fri, 23 Jan 2026 11:55:36 -0800
From: Sean Christopherson <seanjc@...gle.com>
To: Naveen N Rao <naveen@...nel.org>
Cc: Paolo Bonzini <pbonzini@...hat.com>, kvm@...r.kernel.org, linux-kernel@...r.kernel.org, 
	Maxim Levitsky <mlevitsk@...hat.com>, Vasant Hegde <vasant.hegde@....com>, 
	Suravee Suthikulpanit <suravee.suthikulpanit@....com>
Subject: Re: [RFC PATCH 2/3] KVM: SVM: Fix IRQ window inhibit handling across
 multiple vCPUs

On Thu, Jan 22, 2026, Naveen N Rao wrote:
> On Wed, Jan 14, 2026 at 11:55:57AM -0800, Sean Christopherson wrote:
> > I also want to land the optimization separately, so that it can be properly
> > documented, justified, and analyzed by others.
> > 
> > I pushed a rebased version (compile-tested only at this time) with the above change to:
> > 
> >   https://github.com/sean-jc/linux.git svm/avic_irq_window
> > 
> > Can you run you perf tests to see if that aproach also eliminates the degredation
> > relative to avic=0 that you observed?
> 
> Yes, this definitely seems to be helping get rid of that odd performance 
> drop I was seeing earlier. I'll run a couple more tests and report back 
> by next week if I see anything off. Otherwise, this is looking good to 
> me and if you want to apply this to -next, I'm fine with that:
> Tested-by: Naveen N Rao (AMD) <naveen@...nel.org>

Nice, thanks for testing!  I'll post a proper series later today (or early next
week), and will wait until after the merge window to apply (a little too close
for comfort at this point).