On Fri, Aug 14, 2026 at 09:56:30AM -0500, Timothy Pearson wrote:
> With kernel 6.12 (Debian stable) we see a continuously increasing spurious
> interrupt count inside a pSeries guest running on a PowerNV host:
>
> cat /proc/interrupts
> CPU0
> 16: 0 XIVE-IPI 0 Edge IPI-0
> 17: 0 XIVE-IRQ 4096 Edge RAS_EPOW
> 21: 2 XIVE-IRQ 4353 Edge hvc_console
> 23: 0 XIVE-IRQ 4097 Edge RAS_HOTPLUG
> 24: 0 pSeries-PCI-MSI 0 Edge virtio0-config
> 25: 50995 pSeries-PCI-MSI 1 Edge virtio0-input.0
> 26: 45569 pSeries-PCI-MSI 2 Edge virtio0-output.0
> 27: 0 pSeries-PCI-MSI 16384 Edge virtio1-config
> 28: 6 pSeries-PCI-MSI 16385 Edge virtio1-input
> LOC: 5781 Local timer interrupts for timer event device
> BCT: 0 Broadcast timer interrupts for timer event device
> LOC: 2 Local timer interrupts for others
> SPU: 449927 Spurious interrupts
> PMI: 0 Performance monitoring interrupts
> MCE: 0 Machine check exceptions
> NMI: 0 System Reset interrupts
> WDG: 0 Watchdog soft-NMI interrupts
> DBL: 0 Doorbell interrupts
>
> The spurious interrupts are apparently from the virtio0-[input|output]
> devices.
>
I was able to narrow it down to commit ecd10702baae5 ('KVM: PPC: Book3S HV:
Handle pending exceptions on guest entry with MSR_EE')
Reverting the changes in this commit reduces the spurious interrupts
observed considerably. I'll try to root cause the issue and send a fix.
Thanks,
Gautam
