[PATCH v2] virtio-pci: Fix the failure process in kvm_virtio_pci_vector_use_one()

Cindy Lu posted 1 patch 6 months ago
Patches applied successfully (tree, apply log)
git fetch https://github.com/patchew-project/qemu tags/patchew/20240528084840.194538-1-lulu@redhat.com
Maintainers: "Michael S. Tsirkin" <mst@redhat.com>
hw/virtio/virtio-pci.c | 18 ++----------------
1 file changed, 2 insertions(+), 16 deletions(-)
[PATCH v2] virtio-pci: Fix the failure process in kvm_virtio_pci_vector_use_one()
Posted by Cindy Lu 6 months ago
In function kvm_virtio_pci_vector_use_one(), the function will only use
the irqfd/vector for itself. Therefore, in the undo label, the failing
process is incorrect.
To fix this, we can just remove this label.

Fixes: f9a09ca3ea ("vhost: add support for configure interrupt")
Cc: qemu-stable@nongnu.org
Signed-off-by: Cindy Lu <lulu@redhat.com>
---
 hw/virtio/virtio-pci.c | 18 ++----------------
 1 file changed, 2 insertions(+), 16 deletions(-)

diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index b1d02f4b3d..8a9d0f6ef5 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -892,7 +892,7 @@ static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no)
     }
     ret = kvm_virtio_pci_vq_vector_use(proxy, vector);
     if (ret < 0) {
-        goto undo;
+        return ret;
     }
     /*
      * If guest supports masking, set up irqfd now.
@@ -902,25 +902,11 @@ static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no)
         ret = kvm_virtio_pci_irqfd_use(proxy, n, vector);
         if (ret < 0) {
             kvm_virtio_pci_vq_vector_release(proxy, vector);
-            goto undo;
+            return ret;
         }
     }
 
     return 0;
-undo:
-
-    vector = virtio_queue_vector(vdev, queue_no);
-    if (vector >= msix_nr_vectors_allocated(dev)) {
-        return ret;
-    }
-    if (vdev->use_guest_notifier_mask && k->guest_notifier_mask) {
-        ret = virtio_pci_get_notifier(proxy, queue_no, &n, &vector);
-        if (ret < 0) {
-            return ret;
-        }
-        kvm_virtio_pci_irqfd_release(proxy, n, vector);
-    }
-    return ret;
 }
 static int kvm_virtio_pci_vector_vq_use(VirtIOPCIProxy *proxy, int nvqs)
 {
-- 
2.43.0
Re: [PATCH v2] virtio-pci: Fix the failure process in kvm_virtio_pci_vector_use_one()
Posted by Peter Maydell 5 months, 4 weeks ago
On Tue, 28 May 2024 at 09:48, Cindy Lu <lulu@redhat.com> wrote:
>
> In function kvm_virtio_pci_vector_use_one(), the function will only use
> the irqfd/vector for itself. Therefore, in the undo label, the failing
> process is incorrect.
> To fix this, we can just remove this label.
>
> Fixes: f9a09ca3ea ("vhost: add support for configure interrupt")
> Cc: qemu-stable@nongnu.org
> Signed-off-by: Cindy Lu <lulu@redhat.com>

Reported by Coverity: CID 1468940, 1543938.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM