From 80ebfd69b906186a12f0dc892a49188b4d672fdc Mon Sep 17 00:00:00 2001 From: Andrew Melnychenko Date: Wed, 9 Jun 2021 12:58:41 +0300 Subject: [PATCH] virtio-pci: Added check for virtio device presence in mm callbacks. During unplug the virtio device is unplugged from virtio-bus on pci. In some cases, requests to virtio-pci mm may acquire during/after unplug. Added check that virtio device is on the bus, for "common" memory region. Signed-off-by: Andrew Melnychenko Message-Id: <20210609095843.141378-2-andrew@daynix.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/virtio/virtio-pci.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index f1e105fa52..1bef7a2be8 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -1147,6 +1147,10 @@ static uint64_t virtio_pci_common_read(void *opaque, hwaddr addr, uint32_t val = 0; int i; + if (vdev == NULL) { + return UINT64_MAX; + } + switch (addr) { case VIRTIO_PCI_COMMON_DFSELECT: val = proxy->dfselect; @@ -1230,6 +1234,10 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, VirtIOPCIProxy *proxy = opaque; VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); + if (vdev == NULL) { + return; + } + switch (addr) { case VIRTIO_PCI_COMMON_DFSELECT: proxy->dfselect = val;