[PULL 0/2] vfio queue

[PULL 0/2] vfio queue

[Cédric Le Goater]

The following changes since commit 7a1dc45af581d2b643cdbf33c01fd96271616fbd:

  Merge tag 'pull-target-arm-20240126' of https://git.linaro.org/people/pmaydell/qemu-arm into staging (2024-01-26 18:16:35 +0000)

are available in the Git repository at:

  https://github.com/legoater/qemu/ tags/pull-vfio-20240129

for you to fetch changes up to d2b668fca5652760b435ce812a743bba03d2f316:

  vfio/pci: Clear MSI-X IRQ index always (2024-01-29 08:26:25 +0100)

----------------------------------------------------------------
vfio queue:

* Array type cleanup
* Fix for IRQ enablement

----------------------------------------------------------------
Cédric Le Goater (1):
      vfio/pci: Clear MSI-X IRQ index always

Paolo Bonzini (1):
      vfio: use matching sizeof type

 hw/vfio/common.c | 2 +-
 hw/vfio/pci.c    | 8 +++++---
 2 files changed, 6 insertions(+), 4 deletions(-)

[PULL 1/2] vfio: use matching sizeof type

[Cédric Le Goater]

From: Paolo Bonzini <pbonzini@redhat.com>

Do not use uint64_t for the type of the declaration and __u64 when
computing the number of elements in the array.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/vfio/common.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 4aa86f563c64cab9290efab54d20cb2a30c498aa..059bfdc07a85e2eb908df828c1f42104d683e911 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -1118,7 +1118,7 @@ static int vfio_device_dma_logging_report(VFIODevice *vbasedev, hwaddr iova,
 {
     uint64_t buf[DIV_ROUND_UP(sizeof(struct vfio_device_feature) +
                         sizeof(struct vfio_device_feature_dma_logging_report),
-                        sizeof(__u64))] = {};
+                        sizeof(uint64_t))] = {};
     struct vfio_device_feature *feature = (struct vfio_device_feature *)buf;
     struct vfio_device_feature_dma_logging_report *report =
         (struct vfio_device_feature_dma_logging_report *)feature->data;
-- 
2.43.0

[PULL 2/2] vfio/pci: Clear MSI-X IRQ index always

[Cédric Le Goater]

When doing device assignment of a physical device, MSI-X can be
enabled with no vectors enabled and this sets the IRQ index to
VFIO_PCI_MSIX_IRQ_INDEX. However, when MSI-X is disabled, the IRQ
index is left untouched if no vectors are in use. Then, when INTx
is enabled, the IRQ index value is considered incompatible (set to
MSI-X) and VFIO_DEVICE_SET_IRQS fails. QEMU complains with :

qemu-system-x86_64: vfio 0000:08:00.0: Failed to set up TRIGGER eventfd signaling for interrupt INTX-0: VFIO_DEVICE_SET_IRQS failure: Invalid argument

To avoid that, unconditionaly clear the IRQ index when MSI-X is
disabled.

Buglink: https://issues.redhat.com/browse/RHEL-21293
Fixes: 5ebffa4e87e7 ("vfio/pci: use an invalid fd to enable MSI-X")
Cc: Jing Liu <jing2.liu@intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
---
 hw/vfio/pci.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index d7fe06715c4b9cde66a68c31aaf405315921b0d6..4fa387f0430d62ca2ba1b5ae5b7037f8f06b33f9 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -826,9 +826,11 @@ static void vfio_msix_disable(VFIOPCIDevice *vdev)
         }
     }
 
-    if (vdev->nr_vectors) {
-        vfio_disable_irqindex(&vdev->vbasedev, VFIO_PCI_MSIX_IRQ_INDEX);
-    }
+    /*
+     * Always clear MSI-X IRQ index. A PF device could have enabled
+     * MSI-X with no vectors. See vfio_msix_enable().
+     */
+    vfio_disable_irqindex(&vdev->vbasedev, VFIO_PCI_MSIX_IRQ_INDEX);
 
     vfio_msi_disable_common(vdev);
     vfio_intx_enable(vdev, &err);
-- 
2.43.0

Re: [PULL 0/2] vfio queue

[Peter Maydell]

On Mon, 29 Jan 2024 at 08:42, Cédric Le Goater <clg@redhat.com> wrote:
>
> The following changes since commit 7a1dc45af581d2b643cdbf33c01fd96271616fbd:
>
>   Merge tag 'pull-target-arm-20240126' of https://git.linaro.org/people/pmaydell/qemu-arm into staging (2024-01-26 18:16:35 +0000)
>
> are available in the Git repository at:
>
>   https://github.com/legoater/qemu/ tags/pull-vfio-20240129
>
> for you to fetch changes up to d2b668fca5652760b435ce812a743bba03d2f316:
>
>   vfio/pci: Clear MSI-X IRQ index always (2024-01-29 08:26:25 +0100)
>
> ----------------------------------------------------------------
> vfio queue:
>
> * Array type cleanup
> * Fix for IRQ enablement
>
> ----------------------------------------------------------------


Applied, thanks.

Please update the changelog at https://wiki.qemu.org/ChangeLog/9.0
for any user-visible changes.

-- PMM