diff options
| -rw-r--r-- | hw/vfio_pci.c | 30 |
1 files changed, 26 insertions, 4 deletions
diff --git a/hw/vfio_pci.c b/hw/vfio_pci.c index 28c83031d0..8ec1faf27e 100644 --- a/hw/vfio_pci.c +++ b/hw/vfio_pci.c @@ -562,8 +562,8 @@ static int vfio_enable_vectors(VFIODevice *vdev, bool msix) return ret; } -static int vfio_msix_vector_use(PCIDevice *pdev, - unsigned int nr, MSIMessage msg) +static int vfio_msix_vector_do_use(PCIDevice *pdev, unsigned int nr, + MSIMessage *msg, IOHandler *handler) { VFIODevice *vdev = DO_UPCAST(VFIODevice, pdev, pdev); VFIOMSIVector *vector; @@ -587,7 +587,7 @@ static int vfio_msix_vector_use(PCIDevice *pdev, * Attempt to enable route through KVM irqchip, * default to userspace handling if unavailable. */ - vector->virq = kvm_irqchip_add_msi_route(kvm_state, msg); + vector->virq = msg ? kvm_irqchip_add_msi_route(kvm_state, *msg) : -1; if (vector->virq < 0 || kvm_irqchip_add_irqfd_notifier(kvm_state, &vector->interrupt, vector->virq) < 0) { @@ -596,7 +596,7 @@ static int vfio_msix_vector_use(PCIDevice *pdev, vector->virq = -1; } qemu_set_fd_handler(event_notifier_get_fd(&vector->interrupt), - vfio_msi_interrupt, NULL, vector); + handler, NULL, vector); } /* @@ -639,6 +639,12 @@ static int vfio_msix_vector_use(PCIDevice *pdev, return 0; } +static int vfio_msix_vector_use(PCIDevice *pdev, + unsigned int nr, MSIMessage msg) +{ + return vfio_msix_vector_do_use(pdev, nr, &msg, vfio_msi_interrupt); +} + static void vfio_msix_vector_release(PCIDevice *pdev, unsigned int nr) { VFIODevice *vdev = DO_UPCAST(VFIODevice, pdev, pdev); @@ -697,6 +703,22 @@ static void vfio_enable_msix(VFIODevice *vdev) vdev->interrupt = VFIO_INT_MSIX; + /* + * Some communication channels between VF & PF or PF & fw rely on the + * physical state of the device and expect that enabling MSI-X from the + * guest enables the same on the host. When our guest is Linux, the + * guest driver call to pci_enable_msix() sets the enabling bit in the + * MSI-X capability, but leaves the vector table masked. We therefore + * can't rely on a vector_use callback (from request_irq() in the guest) + * to switch the physical device into MSI-X mode because that may come a + * long time after pci_enable_msix(). This code enables vector 0 with + * triggering to userspace, then immediately release the vector, leaving + * the physical device with no vectors enabled, but MSI-X enabled, just + * like the guest view. + */ + vfio_msix_vector_do_use(&vdev->pdev, 0, NULL, NULL); + vfio_msix_vector_release(&vdev->pdev, 0); + if (msix_set_vector_notifiers(&vdev->pdev, vfio_msix_vector_use, vfio_msix_vector_release, NULL)) { error_report("vfio: msix_set_vector_notifiers failed\n"); |