Legacy virtio drivers write to the I/O port BAR, and the modern virtio device uses the MMIO BAR. Since vhost can only listen on one ioeventfd, select the one that the guest will use. Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@xxxxxxx> --- virtio/pci.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/virtio/pci.c b/virtio/pci.c index c02534a6..320865c1 100644 --- a/virtio/pci.c +++ b/virtio/pci.c @@ -83,7 +83,7 @@ static int virtio_pci__init_ioeventfd(struct kvm *kvm, struct virtio_device *vde u16 port_addr = virtio_pci__port_addr(vpci); off_t offset = vpci->doorbell_offset; int r, flags = 0; - int fd; + int pio_fd, mmio_fd; vpci->ioeventfds[vq] = (struct virtio_pci_ioevent_param) { .vdev = vdev, @@ -107,7 +107,7 @@ static int virtio_pci__init_ioeventfd(struct kvm *kvm, struct virtio_device *vde /* ioport */ ioevent.io_addr = port_addr + offset; ioevent.io_len = sizeof(u16); - ioevent.fd = fd = eventfd(0, 0); + ioevent.fd = pio_fd = eventfd(0, 0); r = ioeventfd__add_event(&ioevent, flags | IOEVENTFD_FLAG_PIO); if (r) return r; @@ -115,13 +115,14 @@ static int virtio_pci__init_ioeventfd(struct kvm *kvm, struct virtio_device *vde /* mmio */ ioevent.io_addr = mmio_addr + offset; ioevent.io_len = sizeof(u16); - ioevent.fd = eventfd(0, 0); + ioevent.fd = mmio_fd = eventfd(0, 0); r = ioeventfd__add_event(&ioevent, flags); if (r) goto free_ioport_evt; if (vdev->ops->notify_vq_eventfd) - vdev->ops->notify_vq_eventfd(kvm, vpci->dev, vq, fd); + vdev->ops->notify_vq_eventfd(kvm, vpci->dev, vq, + vdev->legacy ? pio_fd : mmio_fd); return 0; free_ioport_evt: -- 2.36.1