[Qemu-devel] [Bug 1833053] Re: qemu guest crashes on spice client USB redirected device removal

[Alex <1833053@bugs.launchpad.net>]

Hello,
I have the same qemu behaviour. It happens every time I have unplugged physical usb device attached to guest from the host system. My device is USB GSM dongle. Some times it disconnects and reconnects again for unknown reason, may be power loss... With version 3.1.0 qemu (gentoo linux) this disconnects had normal USB device disconnects in guest system. But with version 4.0.0 it gets guest VM to crash.

-- 
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1833053

Title:
  qemu guest crashes on spice client USB redirected device removal

Status in QEMU:
  New

Bug description:
  Hello,

  I am experiencing guest crashes, which cannot be reproduced at all
  times, but are pretty frequent (4 out of 5 tries it would crash). The
  guest crashes when a previously attached USB redirected device through
  SPICE has been removed by the client.

  Steps to reproduce:
  1.) Start windows 10 guest with display driver Spice
  2.) Connect to the console with remote-viewer spice://IP:PORT or via virt-viewer (tunnelled through SSH)
  3.) Attach a client USB device, for example storage device, iPhone or Android phone
  4.) Observe the guest OS detects it and sets it up
  5.) Go back to 'USB device selection' and untick the USB device
  6.) Observe the guest VM crashed and the below assertion was printed in the qemu log for this virtual machine:

  qemu-system-x86_64: /var/tmp/portage/app-emulation/qemu-4.0.0-r3/work/qemu-4.0.0/hw/usb/core.c:720: usb_ep_get: Assertion `dev != NULL' failed.
  2019-06-17 09:25:09.160+0000: shutting down, reason=crashed

  
  Versions of related packages on the host:
  app-emulation/qemu-4.0.0-r3
  app-emulation/spice-0.14.0-r2:0
  app-emulation/spice-protocol-0.12.14:0
  net-misc/spice-gtk-0.35:0
  Kernel: 5.1.7-gentoo on Intel x86_64 CPU

  Version of the spice-tools on the guest:
  virtio-win 0.1-126
  QXL 0.1-21
  mingw-vdagent-win 0.8.0

  QEMU command line (generated by libvirt):

  /usr/bin/qemu-system-x86_64 -name guest=W10VM,debug-threads=on -S
  -object
  secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-41-W10VM
  /master-key.aes -machine pc-i440fx-2.12,accel=kvm,usb=off,vmport=off
  ,dump-guest-core=off -cpu
  qemu64,hv_time,hv_relaxed,hv_vapic,hv_spinlocks=0x1fff,hv_synic,hv_stimer
  -m 4500 -realtime mlock=off -smp
  2,maxcpus=4,sockets=4,cores=1,threads=1 -uuid b39afae2-5085-4659-891c-
  b3c65e65af2e -no-user-config -nodefaults -chardev
  socket,id=charmonitor,fd=26,server,nowait -mon
  chardev=charmonitor,id=monitor,mode=control -rtc
  base=localtime,driftfix=slew -no-hpet -global kvm-
  pit.lost_tick_policy=delay -no-shutdown -global PIIX4_PM.disable_s3=1
  -global PIIX4_PM.disable_s4=1 -boot menu=off,strict=on -device ich9
  -usb-ehci1,id=usb,bus=pci.0,addr=0x5.0x7 -device ich9-usb-
  uhci1,masterbus=usb.0,firstport=0,bus=pci.0,multifunction=on,addr=0x5
  -device ich9-usb-
  uhci2,masterbus=usb.0,firstport=2,bus=pci.0,addr=0x5.0x1 -device ich9
  -usb-uhci3,masterbus=usb.0,firstport=4,bus=pci.0,addr=0x5.0x2 -device
  virtio-scsi-pci,id=scsi0,bus=pci.0,addr=0x8 -device virtio-serial-
  pci,id=virtio-serial0,bus=pci.0,addr=0x6 -drive
  file=/libvirt/images/W10VM.qcow2,format=qcow2,if=none,id=drive-
  scsi0-0-0-1,cache=unsafe,discard=unmap,detect-zeroes=unmap -device
  scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=1,device_id=drive-
  scsi0-0-0-1,drive=drive-scsi0-0-0-1,id=scsi0-0-0-1,bootindex=1,write-
  cache=on -netdev tap,fd=28,id=hostnet0,vhost=on,vhostfd=29 -device
  virtio-net-
  pci,netdev=hostnet0,id=net0,mac=52:54:00:44:f6:21,bus=pci.0,addr=0x3
  -chardev spicevmc,id=charchannel0,name=vdagent -device
  virtserialport,bus=virtio-
  serial0.0,nr=1,chardev=charchannel0,id=channel0,name=com.redhat.spice.0
  -chardev socket,id=charchannel1,fd=30,server,nowait -device
  virtserialport,bus=virtio-
  serial0.0,nr=3,chardev=charchannel1,id=channel1,name=org.qemu.guest_agent.0
  -chardev spiceport,id=charchannel2,name=org.spice-space.webdav.0
  -device virtserialport,bus=virtio-
  serial0.0,nr=2,chardev=charchannel2,id=channel2,name=org.spice-
  space.webdav.0 -spice port=5901,addr=0.0.0.0,seamless-migration=on
  -device qxl-
  vga,id=video0,ram_size=134217728,vram_size=134217728,vram64_size_mb=0,vgamem_mb=64,max_outputs=1,bus=pci.0,addr=0x2
  -device intel-hda,id=sound0,bus=pci.0,addr=0x4 -device hda-
  duplex,id=sound0-codec0,bus=sound0.0,cad=0 -chardev
  spicevmc,id=charredir0,name=usbredir -device usb-
  redir,chardev=charredir0,id=redir0,bus=usb.0,port=1 -chardev
  spicevmc,id=charredir1,name=usbredir -device usb-
  redir,chardev=charredir1,id=redir1,bus=usb.0,port=2 -device virtio-
  balloon-pci,id=balloon0,bus=pci.0,addr=0x7 -sandbox
  on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny
  -msg timestamp=on

  
  I have attempted to collect a backtrace, but will need direction as I am not sure on which thread to listen and where to set the breakpoint, 'thread apply all backtrace' does not seem to work well with the qemu process...

  Thank you

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1833053/+subscriptions