From 899649b7d4ead76c19e39251ca886eebe3f811a8 Mon Sep 17 00:00:00 2001 From: Alex Williamson <alex.williamson@redhat.com> Date: Wed, 10 Oct 2012 09:10:32 -0600 Subject: [PATCH] vfio: Fix PCI INTx disable consistency The virq_disabled flag tracks the userspace view of INTx masking across interrupt mode changes, but we're not consistently applying this to the interrupt and masking handler notion of the device. Currently if the user sets DisINTx while in MSI or MSIX mode, then returns to INTx mode (ex. rebooting a qemu guest), the hardware has DisINTx+, but the management of INTx thinks it's enabled, making it impossible to actually clear DisINTx. Fix this by updating the handler state when INTx is re-enabled. Cc: stable@vger.kernel.org Signed-off-by: Alex Williamson <alex.williamson@redhat.com> --- drivers/vfio/pci/vfio_pci_intrs.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c index c8139a598f8469..3639371fa697e6 100644 --- a/drivers/vfio/pci/vfio_pci_intrs.c +++ b/drivers/vfio/pci/vfio_pci_intrs.c @@ -366,6 +366,17 @@ static int vfio_intx_enable(struct vfio_pci_device *vdev) return -ENOMEM; vdev->num_ctx = 1; + + /* + * If the virtual interrupt is masked, restore it. Devices + * supporting DisINTx can be masked at the hardware level + * here, non-PCI-2.3 devices will have to wait until the + * interrupt is enabled. + */ + vdev->ctx[0].masked = vdev->virq_disabled; + if (vdev->pci_2_3) + pci_intx(vdev->pdev, !vdev->ctx[0].masked); + vdev->irq_type = VFIO_PCI_INTX_IRQ_INDEX; return 0; @@ -419,7 +430,7 @@ static int vfio_intx_set_signal(struct vfio_pci_device *vdev, int fd) * disable_irq won't. */ spin_lock_irqsave(&vdev->irqlock, flags); - if (!vdev->pci_2_3 && (vdev->ctx[0].masked || vdev->virq_disabled)) + if (!vdev->pci_2_3 && vdev->ctx[0].masked) disable_irq_nosync(pdev->irq); spin_unlock_irqrestore(&vdev->irqlock, flags); -- GitLab