Comment 0 for bug 1755912

When using qemu-system-x86_64 with the option -vga qxl, it crashes. The easiest way to crash it is by trying to change the guest's resolution. However, the system may randomly crash too, not happening only when changing resolution. Here is the terminal output of one of these random crashes:

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$ qemu-system-x86_64 -hda /dev/sdb -m 2048 -enable-kvm -cpu host -vga qxl -nodefaults -netdev user,id=hostnet0 -device virtio-net-pci,id=net0,netdev=hostnet0
WARNING: Image format was not specified for '/dev/sdb' and probing guessed raw.
         Automatically detecting the format is dangerous for raw images, write operations on block 0 will be restricted.
         Specify the 'raw' format explicitly to remove the restrictions.

(process:21313): Spice-WARNING **: 16:01:45.759: display-channel.c:2431:display_channel_validate_surface: canvas address is 0x7f8eb948ab18 for 0 (and is NULL)

(process:21313): Spice-WARNING **: 16:01:45.759: display-channel.c:2432:display_channel_validate_surface: failed on 0

(process:21313): Spice-CRITICAL **: 16:01:45.759: display-channel.c:2035:display_channel_update: condition `display_channel_validate_surface(display, surface_id)' failed
Abortado (imagem do núcleo gravada)

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I was running QEMU as a normal user which is on the groups kvm and disk. Initially I supposed the problem was because I was running QEMU as root, but as a normal user this happens too.

I have tested with guests with different Ubuntu version: 18.04, 17.10 and 16.04. It is happening with them all.

ProblemType: Crash
DistroRelease: Ubuntu 18.04
Package: qemu-system-x86 1:2.11+dfsg-1ubuntu4
ProcVersionSignature: Ubuntu 4.15.0-10.11-generic 4.15.3
Uname: Linux 4.15.0-10-generic x86_64
ApportVersion: 2.20.8-0ubuntu10
Architecture: amd64
CurrentDesktop: XFCE
Date: Wed Mar 14 17:13:52 2018
ExecutablePath: /usr/bin/qemu-system-x86_64
InstallationDate: Installed on 2017-06-13 (273 days ago)
InstallationMedia: Xubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412)
KvmCmdLine: COMMAND STAT EUID RUID PID PPID %CPU COMMAND
MachineType: LENOVO 80UG
ProcCmdline: qemu-system-x86_64 -hda /dev/sdb -smp cpus=2 -m 512 -enable-kvm -cpu host -vga qxl -nodefaults -netdev user,id=hostnet0 -device virtio-net-pci,id=net0,netdev=hostnet0
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-10-generic.efi.signed root=UUID=6b4ae5c0-c78c-49a6-a1ba-029192618a7a ro quiet
Signal: 6
SourcePackage: qemu
StacktraceTop:
 () at /usr/lib/x86_64-linux-gnu/libspice-server.so.1
 () at /usr/lib/x86_64-linux-gnu/libspice-server.so.1
 () at /usr/lib/x86_64-linux-gnu/libspice-server.so.1
 () at /usr/lib/x86_64-linux-gnu/libspice-server.so.1
 () at /usr/lib/x86_64-linux-gnu/libspice-server.so.1
Title: qemu-system-x86_64 crashed with SIGABRT
UpgradeStatus: Upgraded to bionic on 2017-10-20 (145 days ago)
UserGroups: adm bluetooth cdrom dialout dip disk kvm libvirt lpadmin netdev plugdev sambashare sudo
dmi.bios.date: 07/10/2017
dmi.bios.vendor: LENOVO
dmi.bios.version: 0XCN43WW
dmi.board.asset.tag: NO Asset Tag
dmi.board.name: Toronto 4A2
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40679 WIN
dmi.chassis.asset.tag: NO Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Lenovo ideapad 310-14ISK
dmi.modalias: dmi:bvnLENOVO:bvr0XCN43WW:bd07/10/2017:svnLENOVO:pn80UG:pvrLenovoideapad310-14ISK:rvnLENOVO:rnToronto4A2:rvrSDK0J40679WIN:cvnLENOVO:ct10:cvrLenovoideapad310-14ISK:
dmi.product.family: IDEAPAD
dmi.product.name: 80UG
dmi.product.version: Lenovo ideapad 310-14ISK
dmi.sys.vendor: LENOVO