On Wed, May 6, 2026, at 9:23 AM, Cédric Le Goater wrote:
> This check was originally introduced in commit b3ebc10c373e
> ("vfio-pci: Add debug config options to disable MSI/X KVM support") as
> part of a debug block to retrieve the MSI/MSIX message, and was later
> moved by commit 0de70dc7bab1 ("vfio/pci: Rename MSI/X functions for
> easier tracing") into the main interrupt handling path, becoming
> production code.
>
> Under normal conditions, this code path cannot be reached because the
> BQL serializes all handler registration, vdev->interrupt updates, and
> handler removal. Replace abort() with g_assert_not_reached(), which is
> preferred nowdays, and add a comment clarifying the purpose.
>
> Cc: Alex Williamson <[email protected]>
> Signed-off-by: Cédric Le Goater <[email protected]>
> ---
> hw/vfio/pci.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index
> 09acd3f6082b0a9c5223780bf7e9847b57424cf7..7ca2ff4e7c1cb570cd60d35454b33b5506dae36e
>
> 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -453,7 +453,12 @@ static void vfio_msi_interrupt(void *opaque)
> get_msg = msi_get_message;
> notify = msi_notify;
> } else {
> - abort();
> + /*
> + * Interrupt state transitions (MSI/MSI-X -> NONE/INTx) are
> + * protected by the BQL, and eventfd handlers are strictly
> + * unregistered before vdev->interrupt is modified.
> + */
> + g_assert_not_reached();
> }
>
> msg = get_msg(pdev, nr);
> --
> 2.54.0
Acked-by: Alex Williamson <[email protected]>
