Re: [PATCH 3/4] selftests/vfio: Extend mix_and_match timeout to 90s

[David Matlack]

On 2026-09-01 03:53 PM, Alex Williamson wrote:
> Systems with firmware first error handling can see heavy SMM load
> as a result of the mix_and_match induced IOMMU errors.  For devices
> like igb that get wedged on these errors, the resulting FLR is delayed
> waiting for the transaction pending register to clear, which never
> occurs.  However, due to the background SMM, the backoff delays in
> PCI code wildly exceed their timeouts.  As a result, the whole test
> can report failure.
> 
> Extend the mix_and_match timeout to a value shown to complete reliably
> on such systems, with ~2x margin.
> 
> Assisted-by: Qwen3.8-27B
> Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>

With the caveat that shortlog should be "vfio: selftests: ...",

Reviewed-by: David Matlack <dmatlack@xxxxxxxxxx>

> ---
>  tools/testing/selftests/vfio/vfio_pci_driver_test.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/vfio/vfio_pci_driver_test.c b/tools/testing/selftests/vfio/vfio_pci_driver_test.c
> index 761bf117d624..1d532f944cee 100644
> --- a/tools/testing/selftests/vfio/vfio_pci_driver_test.c
> +++ b/tools/testing/selftests/vfio/vfio_pci_driver_test.c
> @@ -190,7 +190,7 @@ TEST_F(vfio_pci_driver_test, send_msi)
>  	ASSERT_EQ(1, value);
>  }
>  
> -TEST_F(vfio_pci_driver_test, mix_and_match)
> +TEST_F_TIMEOUT(vfio_pci_driver_test, mix_and_match, 90)
>  {
>  	u64 value;
>  	int i;
> -- 
> 2.53.0
>