From 21027e308bf410293a745d4358a848e9aa037df1 Mon Sep 17 00:00:00 2001 From: Laurent Vivier Date: Mon, 10 May 2021 13:08:20 -0400 Subject: [PATCH 09/15] virtio-net: failover: add missing remove_migration_state_change_notifier() RH-Author: Miroslav Rezanina RH-MergeRequest: 5: Synchronize RHEL-AV 8.5 release 18 to RHEL 9 Beta RH-Commit: [4/12] 884f0f99fbbba4312663ec6232b1d8c9576df84e (mrezanin/centos-src-qemu-kvm) RH-Bugzilla: 1957194 RH-Acked-by: Danilo Cesar Lemes de Paula RH-Acked-by: Cornelia Huck RH-Acked-by: Greg Kurz RH-Acked-by: Laurent Vivier In the failover case configuration, virtio_net_device_realize() uses an add_migration_state_change_notifier() to add a state notifier, but this notifier is not removed by the unrealize function when the virtio-net card is unplugged. If the card is unplugged and a migration is started, the notifier is called and as it is not valid anymore QEMU crashes. This patch fixes the problem by adding the remove_migration_state_change_notifier() in virtio_net_device_unrealize(). The problem can be reproduced with: $ qemu-system-x86_64 -enable-kvm -m 1g -M q35 \ -device pcie-root-port,slot=4,id=root1 \ -device pcie-root-port,slot=5,id=root2 \ -device virtio-net-pci,id=net1,mac=52:54:00:6f:55:cc,failover=on,bus=root1 \ -monitor stdio disk.qcow2 (qemu) device_del net1 (qemu) migrate "exec:gzip -c > STATEFILE.gz" Thread 1 "qemu-system-x86" received signal SIGSEGV, Segmentation fault. 0x0000000000000000 in ?? () (gdb) bt #0 0x0000000000000000 in () #1 0x0000555555d726d7 in notifier_list_notify (...) at .../util/notify.c:39 #2 0x0000555555842c1a in migrate_fd_connect (...) at .../migration/migration.c:3975 #3 0x0000555555950f7d in migration_channel_connect (...) error@entry=0x0) at .../migration/channel.c:107 #4 0x0000555555910922 in exec_start_outgoing_migration (...) at .../migration/exec.c:42 Reported-by: Igor Mammedov Reviewed-by: Dr. David Alan Gilbert Reviewed-by: Michael S. Tsirkin Signed-off-by: Laurent Vivier Signed-off-by: Jason Wang (cherry picked from commit a7eca58380f9589bb1bb6333ccfb58869734edb6) Signed-off-by: Laurent Vivier Signed-off-by: Danilo C. L. de Paula Signed-off-by: Miroslav Rezanina --- hw/net/virtio-net.c | 1 + 1 file changed, 1 insertion(+) diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c index 66b9ff4511..914051feb7 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -3373,6 +3373,7 @@ static void virtio_net_device_unrealize(DeviceState *dev) if (n->failover) { device_listener_unregister(&n->primary_listener); + remove_migration_state_change_notifier(&n->migration_state); } max_queues = n->multiqueue ? n->max_queues : 1; -- 2.27.0