semantic: 0.277
device: 0.164
graphic: 0.147
other: 0.091
socket: 0.062
permissions: 0.046
files: 0.043
network: 0.034
debug: 0.029
PID: 0.027
vnc: 0.025
boot: 0.020
performance: 0.019
KVM: 0.018
KVM: 0.675
device: 0.104
debug: 0.099
files: 0.033
other: 0.020
PID: 0.014
socket: 0.011
network: 0.009
performance: 0.008
semantic: 0.008
boot: 0.006
graphic: 0.005
vnc: 0.004
permissions: 0.004

commit: 4fe6d78 "virtio: postpone the execution of event_notifier_cleanup function" will cause vhost-user device crash

The new commit: 4fe6d78 break the existing vhost-user devices, such as vhost-user-scsi/blk and vhost-vsocks when exit the host driver,  kvm_io_ioeventfd_del will hit the abort().

Thanks for the bug report. Patch has now been reverted:
https://git.qemu.org/?p=qemu.git;a=commitdiff;h=1ef8185a0613dd2ed2