Re: [PATCH v2 07/14] KVM: selftests: Add support for physical device MSI triggers

Sean Christopherson
2026-04-01T20:24:48Z

On Tue, Mar 31, 2026, Josh Hilke wrote:
> From: David Matlack <dmatlack@google.com>
>
> Add the '-d' flag to vfio_pci_irq_test to trigger interrupts using the
> physical device hardware instead of emulating them via eventfd writes.
> This leverages the VFIO library's driver support to provide a more
> realistic validation of the hardware-to-guest interrupt path.

I don't think this should be optional, I think the test should unconditionally
validate both path. The "signal eventfd directly" is effectively a smoke test
of the full functionality; if that doesn't work, validating that sending via the
device itself is pointless.

To keep the runtime reasonable, maybe do only 10% of the iterations for the eventfd
version, capped at a lowish hardcoded value?