Re: [RFC] KVM: Proposed uAPI for querying GSI and irqbypass status

[Sean Christopherson <seanjc@google.com>]

On Wed, Aug 05, 2026, Marc Zyngier wrote:
> On Wed, 05 Aug 2026 09:26:56 +0100,
> Mostafa Saleh <smostafa@google.com> wrote:
> > 
> > Hi Jing,
> > 
> > On Fri, Jul 31, 2026 at 10:26:26AM -0700, Jing Zhang wrote:
> 
> [drop the LLM generated stuff]
> 
> > > While interfaces in debugfs are fantastic for manual, retroactive
> > > debugging on a developer workstation, they are not Dependable for
> > > fleet-wide observability. This RFC aims to provide a proactive
> > > monitoring solution that aligns KVM with production operational
> > > requirements across architectures (both ARM and x86).
> > > 
> > > Would love to hear your thoughts on this perspective.
> > 
> > I agree that debugfs is not suitable for that purpose.
> > 
> > My main concerns are:
> > 1- Why is /proc/interrupts not enough, it should show whether the
> > interrupts are going through the host (not bypassed) and it should
> > show when the host get a doorbell if the vCPU was not resident.
> 
> This.
> 
> Also, there is a very long standing ask to represent the output of
> /proc/interrupts as a structured set, retrieved through a generic
> kernel interface. I.e. *not* something KVM specific.

+1 to not making this level of detail KVM specific.  Ideally, I'd want more than
what /proc/interrupts offers, e.g. it'd be nice to capture what "mode" an IRQ is
configured for (normal/remapped, IRQ bypass, x86's posted MSI, etc.).  But that's
an argument for extending /proc/irq and/or providing structured output of _that_,
not for throwing something into KVM.