Re: [Qemu-devel] [BUG] I/O thread segfault for QEMU on s390x

[Farhan Ali]

On 03/02/2018 01:13 AM, Fam Zheng wrote:
> On Thu, Mar 1, 2018 at 10:33 PM, Farhan Ali <address@hidden> wrote:
> > Hi,
> >
> > I have been noticing some segfaults for QEMU on s390x, and I have been
> > hitting this issue quite reliably (at least once in 10 runs of a test case).
> > The qemu version is 2.11.50, and I have systemd created coredumps
> > when this happens.
>
> Can you describe the test case or suggest how to reproduce it for us?
>
> Fam

The test case is with a single guest, running a memory intensive 
workload. The guest has 8 vpcus and 4G of memory.

Here is the qemu command line, if that helps:

/usr/bin/qemu-kvm -name guest=sles,debug-threads=on \
-S -object 
secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-2-sles/master-key.aes 
\
-machine s390-ccw-virtio-2.12,accel=kvm,usb=off,dump-guest-core=off \
-m 4096 -realtime mlock=off -smp 8,sockets=8,cores=1,threads=1 \
-object iothread,id=iothread1 -object iothread,id=iothread2 -uuid 
b83a596b-3a1a-4ac9-9f3e-d9a4032ee52c \
-display none -no-user-config -nodefaults -chardev 
socket,id=charmonitor,path=/var/lib/libvirt/qemu/domain-2-sles/monitor.sock,server,nowait 

-mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc 
-no-shutdown \
-boot strict=on -drive 
file=/dev/mapper/360050763998b0883980000002400002b,format=raw,if=none,id=drive-virtio-disk0,cache=none,aio=native 
-device 
virtio-blk-ccw,iothread=iothread1,scsi=off,devno=fe.0.0001,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 
-drive 
file=/dev/mapper/360050763998b0883980000002800002f,format=raw,if=none,id=drive-virtio-disk1,cache=none,aio=native 
-device 
virtio-blk-ccw,iothread=iothread2,scsi=off,devno=fe.0.0002,drive=drive-virtio-disk1,id=virtio-disk1 
-netdev tap,fd=24,id=hostnet0,vhost=on,vhostfd=26 -device 
virtio-net-ccw,netdev=hostnet0,id=net0,mac=02:38:a6:36:e8:1f,devno=fe.0.0000 
-chardev pty,id=charconsole0 -device 
sclpconsole,chardev=charconsole0,id=console0 -device 
virtio-balloon-ccw,id=balloon0,devno=fe.3.ffba -msg timestamp=on


Please let me know if I need to provide any other information.

Thanks
Farhan