From 96412e68c312ae4d91d6febc2284951f8b295ef7 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Fri, 20 Sep 2013 16:58:00 +0200 Subject: [PATCH] virtio-pci: add device_unplugged callback This fixes a crash in hot-unplug of virtio-pci devices behind a PCIe switch. The crash happens because the ioeventfd is still set whent the child is destroyed (destruction happens in postorder). Then the proxy tries to unset to ioeventfd, but the virtqueue structure that holds the EventNotifier has been trashed in the meanwhile. kvm_set_ioeventfd_pio does not expect failure and aborts. The fix is simply to move parts of uninitialization to a new device_unplugged callback, which is called before the child is destroyed. Cc: qemu-stable@nongnu.org Signed-off-by: Paolo Bonzini --- hw/virtio/virtio-pci.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index be18e92..1a363ca 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -1001,6 +1001,15 @@ static void virtio_pci_device_plugged(DeviceState *d) proxy->host_features); } +static void virtio_pci_device_unplugged(DeviceState *d) +{ + PCIDevice *pci_dev = PCI_DEVICE(d); + VirtIOPCIProxy *proxy = VIRTIO_PCI(d); + + virtio_pci_stop_ioeventfd(proxy); + msix_uninit_exclusive_bar(pci_dev); +} + static int virtio_pci_init(PCIDevice *pci_dev) { VirtIOPCIProxy *dev = VIRTIO_PCI(pci_dev); @@ -1015,9 +1024,7 @@ static int virtio_pci_init(PCIDevice *pci_dev) static void virtio_pci_exit(PCIDevice *pci_dev) { VirtIOPCIProxy *proxy = VIRTIO_PCI(pci_dev); - virtio_pci_stop_ioeventfd(proxy); memory_region_destroy(&proxy->bar); - msix_uninit_exclusive_bar(pci_dev); } static void virtio_pci_reset(DeviceState *qdev) @@ -1552,6 +1559,7 @@ static void virtio_pci_bus_class_init(ObjectClass *klass, void *data) k->set_guest_notifiers = virtio_pci_set_guest_notifiers; k->vmstate_change = virtio_pci_vmstate_change; k->device_plugged = virtio_pci_device_plugged; + k->device_unplugged = virtio_pci_device_unplugged; } static const TypeInfo virtio_pci_bus_info = {