Re: [Qemu-devel] qemu 2.0.0-rc2 crash

[Marcel Apfelbaum <marcel.apfelbaum@gmail.com>]

On Thu, 2014-04-10 at 14:55 +0200, Marcin Gibuła wrote:
> Hi,
> 
> I've been playing with QEMU 2.0-rc2 and found a crash that isn't there 
> in 1.7.1.
Hi Marcin,
Thanks for reporting the bug!

Do you have a development environment?
If you do, and the reproduction is fast (and you already have a setup),
a git bisect to find the problematic commit would be appreciated,

Thanks,
Marcel

> 
> Virtual machine is created via libvirt and when I query it with 
> 'dommemstat' it crashes with following backtrace:
> 
> Program received signal SIGSEGV, Segmentation fault.
> 0x00007f5883655c0a in object_class_dynamic_cast (class=0x7f588618fbb0, 
> typename=typename@entry=0x7f58837ebe54 "object") at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/qom/object.c:525
> 525 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/qom/object.c: 
> No such file or directory.
> (gdb) bt
> #0  0x00007f5883655c0a in object_class_dynamic_cast 
> (class=0x7f588618fbb0, typename=typename@entry=0x7f58837ebe54 "object") 
> at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/qom/object.c:525
> #1  0x00007f5883655da5 in object_dynamic_cast (obj=0x7f58861604c0, 
> typename=typename@entry=0x7f58837ebe54 "object") at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/qom/object.c:456
> #2  0x00007f5883657d6e in object_resolve_abs_path (parent=<optimized 
> out>, parts=parts@entry=0x7f5886352ad0, 
> typename=typename@entry=0x7f58837ebe54 "object", index=index@entry=1)
>      at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/qom/object.c:1244
> #3  0x00007f5883657f20 in object_resolve_path_type (path=<optimized 
> out>, typename=0x7f58837ebe54 "object", ambiguous=0x7fff1ccab257) at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/qom/object.c:1312
> #4  0x00007f5883652d7f in qmp_qom_list (path=0x7f588615c9a0 
> "//machine/i440fx/pci.0/child[9]", errp=errp@entry=0x7fff1ccab290) at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/qmp.c:201
> #5  0x00007f588364dd55 in qmp_marshal_input_qom_list (mon=<optimized 
> out>, qdict=<optimized out>, ret=0x7fff1ccab310) at qmp-marshal.c:2490
> #6  0x00007f58836ef4e8 in qmp_call_cmd (params=0x7f58893626b0, 
> mon=0x7f5885c9ec90, cmd=<optimized out>) at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/monitor.c:4760
> #7  handle_qmp_command (parser=<optimized out>, tokens=<optimized out>) 
> at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/monitor.c:4826
> #8  0x00007f588378289a in json_message_process_token 
> (lexer=0x7f5885ca00a0, token=0x7f58861a0500, type=JSON_OPERATOR, x=95, 
> y=20) at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/qobject/json-streamer.c:87
> #9  0x00007f5883797c4f in json_lexer_feed_char 
> (lexer=lexer@entry=0x7f5885ca00a0, ch=125 '}', flush=flush@entry=false) 
> at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/qobject/json-lexer.c:303
> #10 0x00007f5883797d96 in json_lexer_feed (lexer=0x7f5885ca00a0, 
> buffer=<optimized out>, size=<optimized out>) at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/qobject/json-lexer.c:356
> #11 0x00007f5883782ab1 in json_message_parser_feed (parser=<optimized 
> out>, buffer=<optimized out>, size=<optimized out>) at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/qobject/json-streamer.c:110
> #12 0x00007f58836ed593 in monitor_control_read (opaque=<optimized out>, 
> buf=<optimized out>, size=<optimized out>) at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/monitor.c:4847
> #13 0x00007f588363d4e1 in qemu_chr_be_write (len=<optimized out>, 
> buf=0x7fff1ccab4f0 "}", s=0x7f5885caf0b0) at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/qemu-char.c:165
> #14 tcp_chr_read (chan=<optimized out>, cond=<optimized out>, 
> opaque=0x7f5885caf0b0) at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/qemu-char.c:2487
> #15 0x00007f58814d0b75 in g_main_context_dispatch () from 
> /usr/lib64/libglib-2.0.so.0
> #16 0x00007f588360b0e8 in glib_pollfds_poll () at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/main-loop.c:190
> #17 os_host_main_loop_wait (timeout=<optimized out>) at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/main-loop.c:235
> #18 main_loop_wait (nonblocking=<optimized out>) at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/main-loop.c:484
> #19 0x00007f58834dbb6e in main_loop () at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/vl.c:2051
> #20 main (argc=<optimized out>, argv=<optimized out>, envp=<optimized 
> out>) at 
> /var/tmp/portage/app-emulation/qemu-2.0.0_rc2/work/qemu-2.0.0-rc2/vl.c:4507
> 
> Virtual machine options command line:
> 
> LC_ALL=C 
> PATH=/bin:/sbin:/bin:/sbin:/usr/bin:/usr/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin 
> HOME=/ USER=root QEMU_AUDIO_DRV=none /usr/bin/qemu-kvm -name 
> f1b3b8b7-7b0e-4eab-afef-06d577d6544d -S -machine 
> pc-i440fx-2.0,accel=kvm,usb=off -cpu SandyBridge,-kvmclock -m 4096 
> -realtime mlock=on -smp 4,sockets=2,cores=10,threads=1 -uuid 
> f1b3b8b7-7b0e-4eab-afef-06d577d6544d -smbios type=0,vendor=HAL 9000 
> -smbios type=1,manufacturer=cloud -no-user-config -nodefaults -chardev 
> socket,id=charmonitor,path=/var/lib/libvirt/qemu/f1b3b8b7-7b0e-4eab-afef-06d577d6544d.monitor,server,nowait 
> -mon chardev=charmonitor,id=monitor,mode=control -rtc 
> base=utc,clock=vm,driftfix=slew -global kvm-pit.lost_tick_policy=discard 
> -no-shutdown -boot menu=off,strict=on -device 
> piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 -device 
> virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x4 -drive 
> file=/mnt/nfs/volumes/16162d6c-88c9-4052-9ae0-dccdd914a891/active.qcow2,if=none,id=drive-virtio-disk0,format=qcow2,cache=none,aio=threads,bps_rd=68157440,bps_wr=68157440,iops_rd=325,iops_wr=325 
> -device 
> virtio-blk-pci,scsi=off,bus=pci.0,addr=0x5,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=2 
> -drive if=none,id=drive-ide0-0-0,readonly=on,format=raw -device 
> ide-cd,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0,bootindex=1 
> -netdev tap,fd=26,id=hostnet0,vhost=on,vhostfd=27 -device 
> virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:46:0d:c9,bus=pci.0,addr=0x3 
> -chardev pty,id=charserial0 -device 
> isa-serial,chardev=charserial0,id=serial0 -chardev 
> socket,id=charchannel0,path=/var/lib/libvirt/qemu/f1b3b8b7-7b0e-4eab-afef-06d577d6544d.agent,server,nowait 
> -device 
> virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.0 
> -chardev 
> socket,id=charchannel1,path=/var/lib/libvirt/qemu/f1b3b8b7-7b0e-4eab-afef-06d577d6544d.cloud.agent,server,nowait 
> -device 
> virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel1,id=channel1,name=com.cloud.guest_agent.1 
> -device usb-tablet,id=input0 -vnc 0.0.0.0:3,password -device 
> cirrus-vga,id=video0,bus=pci.0,addr=0x2 -device 
> virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x6 -sandbox on -device 
> pvpanic
>