From 7abba7c638ab809e626f379617cb8590a733eabf Mon Sep 17 00:00:00 2001 From: Cindy Lu Date: Tue, 9 Nov 2021 10:37:44 +0800 Subject: [PATCH] virtio-mmio : fix the crash in the vm shutdown The root cause for this crash is the ioeventfd not stopped while the VM stop. The callback for vmstate_change was not implement in virtio-mmio bus Reproduce step load the vm with -M microvm \ -netdev tap,id=net0,vhostforce,script=no,downscript=no \ -device virtio-net-device,netdev=net0\ After the VM boot, login the vm and then shutdown the vm System will crash [Current thread is 1 (Thread 0x7ffff6edde00 (LWP 374378))] (gdb) bt 0 0x00005555558f18b4 in qemu_flush_or_purge_queued_packets (purge=false, nc=0x55500252e850) at ../net/net.c:636 1 qemu_flush_queued_packets (nc=0x55500252e850) at ../net/net.c:656 2 0x0000555555b6c363 in virtio_queue_notify_vq (vq=0x7fffe7e2b010) at ../hw/virtio/virtio.c:2339 3 virtio_queue_host_notifier_read (n=0x7fffe7e2b08c) at ../hw/virtio/virtio.c:3583 4 0x0000555555de7b5a in aio_dispatch_handler (ctx=ctx@entry=0x5555567c5780, node=0x555556b83fd0) at ../util/aio-posix.c:329 5 0x0000555555de8454 in aio_dispatch_ready_handlers (ready_list=, ctx=) at ../util/aio-posix.c:359 6 aio_poll (ctx=0x5555567c5780, blocking=blocking@entry=false) at ../util/aio-posix.c:662 7 0x0000555555cce0cc in monitor_cleanup () at ../monitor/monitor.c:645 8 0x0000555555b06bd2 in qemu_cleanup () at ../softmmu/runstate.c:822 9 0x000055555586e693 in main (argc=, argv=, envp=) at ../softmmu/main.c:51 Signed-off-by: Cindy Lu Message-Id: <20211109023744.22387-1-lulu@redhat.com> Acked-by: Jason Wang Signed-off-by: Michael S. Tsirkin --- hw/virtio/virtio-mmio.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/hw/virtio/virtio-mmio.c b/hw/virtio/virtio-mmio.c index 7b3ebca178..72da12fea5 100644 --- a/hw/virtio/virtio-mmio.c +++ b/hw/virtio/virtio-mmio.c @@ -817,6 +817,17 @@ static char *virtio_mmio_bus_get_dev_path(DeviceState *dev) return path; } +static void virtio_mmio_vmstate_change(DeviceState *d, bool running) +{ + VirtIOMMIOProxy *proxy = VIRTIO_MMIO(d); + + if (running) { + virtio_mmio_start_ioeventfd(proxy); + } else { + virtio_mmio_stop_ioeventfd(proxy); + } +} + static void virtio_mmio_bus_class_init(ObjectClass *klass, void *data) { BusClass *bus_class = BUS_CLASS(klass); @@ -832,6 +843,7 @@ static void virtio_mmio_bus_class_init(ObjectClass *klass, void *data) k->ioeventfd_enabled = virtio_mmio_ioeventfd_enabled; k->ioeventfd_assign = virtio_mmio_ioeventfd_assign; k->pre_plugged = virtio_mmio_pre_plugged; + k->vmstate_change = virtio_mmio_vmstate_change; k->has_variable_vring_alignment = true; bus_class->max_dev = 1; bus_class->get_dev_path = virtio_mmio_bus_get_dev_path;