[Qemu-devel] [Bug 1570134] Re: While committing snapshot qemu crashes with SIGABRT

[Matthew Schumacher]

Max,

Qemu still crashes for me, but the debug is again very different.  When
I attach to the qemu process from gdb, it is unable to provide a
backtrace when it crashes.  The log file is different too.  Any ideas?

qemu-system-x86_64: block.c:2307: bdrv_replace_in_backing_chain:
Assertion `!bdrv_requests_pending(old)' failed.

(gdb) attach 5563
Attaching to process 5563
Reading symbols from /usr/bin/qemu-system-x86_64...cdone.
oReading symbols from /usr/lib64/libepoxy.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libdrm.so.2...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libgbm.so.1...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libX11.so.6...n(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libz.so.1...(no debugging symbols found)...done.
Reading symbols from /lib64/libaio.so.1...(no debugging symbols found)...done.
Reading symbols from /usr/lib64/libiscsi.so.4...done.
Reading symbols from /usr/lib64/libcurl.so.4...(no debugging symbols 
found)...done.
Reading symbols from /lib64/libacl.so.1...(no debugging symbols found)...done.
Reading symbols from /usr/lib64/libgfapi.so.0...done.
Reading symbols from /usr/lib64/libglusterfs.so.0...done.
Reading symbols from /usr/lib64/libgfrpc.so.0...done.
Reading symbols from /usr/lib64/libgfxdr.so.0...done.
Reading symbols from /lib64/libuuid.so.1...(no debugging symbols found)...done.
Reading symbols from /usr/lib64/libssh2.so.1...done.
Reading symbols from /lib64/libbz2.so.1...(no debugging symbols found)...done.
Reading symbols from /usr/lib64/libpixman-1.so.0...(no debugging symbols 
found)...done.
Reading symbols from /lib64/libutil.so.1...(no debugging symbols found)...done.
Reading symbols from /lib64/libncurses.so.5...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libpng16.so.16...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libjpeg.so.62...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libsasl2.so.3...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libSDL-1.2.so.0...(no debugging symbols 
found)...done.
Reading symbols from /lib64/libpthread.so.0...(no debugging symbols 
found)...done.
[New LWP 5588]
[New LWP 5587]
[New LWP 5586]
[New LWP 5585]
[New LWP 5584]
[New LWP 5583]
[New LWP 5582]
[New LWP 5581]
[New LWP 5580]
[New LWP 5579]
[New LWP 5578]
[New LWP 5577]
[New LWP 5576]
[New LWP 5575]
[New LWP 5574]
[New LWP 5573]
[New LWP 5572]
[New LWP 5571]
[New LWP 5570]
[New LWP 5568]
[New LWP 5567]
[New LWP 5566]
[New LWP 5564]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
Reading symbols from /usr/lib64/libvte.so.9...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libgtk-x11-2.0.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libgdk-x11-2.0.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libpangocairo-1.0.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libatk-1.0.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libgdk_pixbuf-2.0.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libpangoft2-1.0.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libpango-1.0.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libfontconfig.so.1...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libfreetype.so.6...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libgio-2.0.so.0...t(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libgobject-2.0.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libglib-2.0.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libcairo.so.2...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libXext.so.6...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libnettle.so.6...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libgnutls.so.30...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/liblzo2.so.2...done.
Reading symbols from /usr/lib64/libspice-server.so.1...done.
Reading symbols from /usr/lib64/libcacard.so.0...done.
Reading symbols from /usr/lib64/libusb-1.0.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libgthread-2.0.so.0...(no debugging symbols 
found)...done.
Reading symbols from /lib64/librt.so.1...(no debugging symbols found)...done.
Reading symbols from /usr/lib64/libstdc++.so.6...(no debugging symbols 
found)...done.
Reading symbols from /lib64/libm.so.6...i(no debugging symbols found)...done.
Reading symbols from /usr/lib64/libgcc_s.so.1...(no debugging symbols 
found)...done.
Reading symbols from /lib64/libc.so.6...(no debugging symbols found)...done.
Reading symbols from /lib64/ld-linux-x86-64.so.2...(no debugging symbols 
found)...done.
Reading symbols from /lib64/libdl.so.2...(no debugging symbols found)...done.
Reading symbols from /usr/lib64/libexpat.so.1...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libxcb.so.1...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libXau.so.6...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libXdmcp.so.6...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libgcrypt.so.20...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libgpg-error.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libidn.so.11...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libssl.so.1...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libcrypto.so.1...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/liblber-2.4.so.2...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libldap-2.4.so.2...(no debugging symbols 
found)...done.
Reading symbols from /lib64/libattr.so.1...(no debugging symbols found)...done.
Reading symbols from /lib64/libresolv.so.2...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libXrandr.so.2...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libXrender.so.1...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libvga.so.1...done.
Reading symbols from /usr/lib64/../lib64/libgmodule-2.0.so.0...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libffi.so.6...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/../lib64/libharfbuzz.so.0...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libEGL.so.1...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/../lib64/libxcb-shm.so.0...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libGL.so.1...n(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/../lib64/libglapi.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/../lib64/libXdamage.so.1...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libXfixes.so.3...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/../lib64/libX11-xcb.so.1...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libxcb-glx.so.0...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libxcb-dri2.so.0...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libxcb-dri3.so.0...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libxcb-present.so.0...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libxcb-randr.so.0...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libxcb-xfixes.so.0...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libxcb-render.so.0...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libxcb-shape.so.0...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libxcb-sync.so.1...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libxshmfence.so.1...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libXxf86vm.so.1...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libXinerama.so.1...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libXi.so.6...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/../lib64/libXcursor.so.1...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/../lib64/libXcomposite.so.1...(no debugging 
symbols found)...done.
Reading symbols from /usr/lib64/libp11-kit.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libhogweed.so.4...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libgmp.so.10...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libnss3.so...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libsmime3.so...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libssl3.so...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libsoftokn3.so...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libnssutil3.so...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libplds4.so...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libplc4.so...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libnspr4.so...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libsqlite3.so.0...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libicui18n.so.56...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libicuuc.so.56...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libicudata.so.56...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libcelt051.so.0...done.
Reading symbols from /usr/lib64/liblz4.so.1...(no debugging symbols 
found)...done.
Reading symbols from /lib64/libudev.so.1...(no debugging symbols found)...done.
Reading symbols from /usr/lib64/sasl2/libsasldb.so.3...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/libgdbm.so.4...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/sasl2/libotp.so.3...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/sasl2/libdigestmd5.so.3...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/sasl2/libcrammd5.so.3...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/sasl2/liblogin.so.3...(no debugging symbols 
found)...done.
Reading symbols from /lib64/libcrypt.so.1...(no debugging symbols found)...done.
Reading symbols from /usr/lib64/sasl2/libplain.so.3...(no debugging symbols 
found)...done.
Reading symbols from /usr/lib64/sasl2/libscram.so.3...(no debugging symbols 
found)...done.
0x00007f12852f83d1 in ppoll () from /lib64/libc.so.6
(gdb) continue
Continuing.


[Thread 0x7f115b7fe700 (LWP 5576) exited]
[Thread 0x7f127aa76700 (LWP 5566) exited]
[Thread 0x7f1159ffb700 (LWP 5579) exited]
[Thread 0x7f115affd700 (LWP 5577) exited]
[Thread 0x7f116a0e2700 (LWP 5571) exited]
[Thread 0x7f1158ff9700 (LWP 5581) exited]
[Thread 0x7f11690e0700 (LWP 5573) exited]
[Thread 0x7f11597fa700 (LWP 5580) exited]
[Thread 0x7f115bfff700 (LWP 5575) exited]
[Thread 0x7f11688df700 (LWP 5574) exited]
[Thread 0x7f115a7fc700 (LWP 5578) exited]
[Thread 0x7f11698e1700 (LWP 5572) exited]


[New Thread 0x7f11698e1700 (LWP 5631)]
[New Thread 0x7f115a7fc700 (LWP 5632)]
[New Thread 0x7f11688df700 (LWP 5633)]
[New Thread 0x7f115bfff700 (LWP 5634)]
[New Thread 0x7f127aa76700 (LWP 5635)]
[New Thread 0x7f116a0e2700 (LWP 5636)]
[New Thread 0x7f11690e0700 (LWP 5637)]
[New Thread 0x7f115b7fe700 (LWP 5638)]
[New Thread 0x7f115affd700 (LWP 5639)]
[New Thread 0x7f1159ffb700 (LWP 5640)]
[New Thread 0x7f11597fa700 (LWP 5641)]
[New Thread 0x7f1158ff9700 (LWP 5642)]
[New Thread 0x7f1117fff700 (LWP 5643)]
[New Thread 0x7f11177fe700 (LWP 5644)]
[New Thread 0x7f1116ffd700 (LWP 5645)]
[New Thread 0x7f11167fc700 (LWP 5646)]
[New Thread 0x7f1115ffb700 (LWP 5647)]
[New Thread 0x7f11157fa700 (LWP 5648)]
[New Thread 0x7f1114ff9700 (LWP 5649)]
[New Thread 0x7f11147f8700 (LWP 5650)]
[New Thread 0x7f1113ff7700 (LWP 5651)]
[New Thread 0x7f11137f6700 (LWP 5652)]
[New Thread 0x7f1112ff5700 (LWP 5653)]

Thread 1 "qemu-system-x86" received signal SIGABRT, Aborted.
0x00007f12852323f8 in raise () from /lib64/libc.so.6
(gdb) 
Continuing.
Couldn't get registers: No such process.
Couldn't get registers: No such process.
Couldn't get registers: No such process.
(gdb) 
Continuing.
Couldn't get registers: No such process.
(gdb) [Thread 0x7f1112ff5700 (LWP 5653) exited]
[Thread 0x7f11137f6700 (LWP 5652) exited]
[Thread 0x7f1113ff7700 (LWP 5651) exited]
[Thread 0x7f11147f8700 (LWP 5650) exited]
[Thread 0x7f1114ff9700 (LWP 5649) exited]
[Thread 0x7f11157fa700 (LWP 5648) exited]
[Thread 0x7f1115ffb700 (LWP 5647) exited]
[Thread 0x7f1116ffd700 (LWP 5645) exited]
[Thread 0x7f11177fe700 (LWP 5644) exited]
[Thread 0x7f1117fff700 (LWP 5643) exited]
[Thread 0x7f1158ff9700 (LWP 5642) exited]
[Thread 0x7f11597fa700 (LWP 5641) exited]
[Thread 0x7f1159ffb700 (LWP 5640) exited]
[Thread 0x7f115affd700 (LWP 5639) exited]
[Thread 0x7f115b7fe700 (LWP 5638) exited]
[Thread 0x7f11690e0700 (LWP 5637) exited]
[Thread 0x7f116a0e2700 (LWP 5636) exited]
[Thread 0x7f127aa76700 (LWP 5635) exited]
[Thread 0x7f115bfff700 (LWP 5634) exited]
[Thread 0x7f11688df700 (LWP 5633) exited]
[Thread 0x7f115a7fc700 (LWP 5632) exited]
[Thread 0x7f11698e1700 (LWP 5631) exited]
[Thread 0x7f1134ff9700 (LWP 5588) exited]
[Thread 0x7f11357fa700 (LWP 5587) exited]
[Thread 0x7f1135ffb700 (LWP 5586) exited]
[Thread 0x7f11367fc700 (LWP 5585) exited]
[Thread 0x7f1136ffd700 (LWP 5584) exited]
[Thread 0x7f11377fe700 (LWP 5583) exited]
[Thread 0x7f1137fff700 (LWP 5582) exited]
[Thread 0x7f1272dff700 (LWP 5570) exited]
[Thread 0x7f1278961700 (LWP 5568) exited]
[Thread 0x7f1279162700 (LWP 5567) exited]
[Thread 0x7f127b277700 (LWP 5564) exited]
[Thread 0x7f128d35cb00 (LWP 5563) exited]

Continuing.
Cannot execute this command without a live selected thread.
(gdb) 
Continuing.
Cannot execute this command without a live selected thread.
(gdb) 
Continuing.
Cannot execute this command without a live selected thread.
(gdb)

-- 
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https://bugs.launchpad.net/bugs/1570134

Title:
  While committing snapshot qemu crashes with SIGABRT

Status in QEMU:
  New

Bug description:
  Information:

  OS: Slackware64-Current
  Compiled with: gcc version 5.3.0 (GCC)  / glibc 2.23
  Compiled using: 

  CFLAGS="-O2 -fPIC" \
  CXXFLAGS="-O2 -fPIC" \
  LDFLAGS="-L/usr/lib64" \
  ./configure \
    --prefix=/usr \
    --sysconfdir=/etc \
    --localstatedir=/var \
    --libdir=/usr/lib64 \
    --enable-spice \
    --enable-kvm \
    --enable-glusterfs \
    --enable-libiscsi \
    --enable-libusb \
    --target-list=x86_64-softmmu,i386-softmmu \
    --enable-debug

  Source: qemu-2.5.1.tar.bz2

  Running as:

  /usr/bin/qemu-system-x86_64 -name test1,debug-threads=on -S -machine
  pc-1.1,accel=kvm,usb=off -m 4096 -realtime mlock=off -smp
  2,sockets=2,cores=1,threads=1 -uuid
  4b30ec13-6609-4a56-8731-d400c38189ef -no-user-config -nodefaults
  -chardev
  
socket,id=charmonitor,path=/var/lib/libvirt/qemu/domain-4-test1/monitor.sock,server,nowait
  -mon chardev=charmonitor,id=monitor,mode=control -rtc
  base=localtime,clock=vm,driftfix=slew -global kvm-
  pit.lost_tick_policy=discard -no-shutdown -boot strict=on -device
  piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 -drive
  file=/datastore/vm/test1/test1.img,format=qcow2,if=none,id=drive-
  virtio-disk0 -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x4,drive
  =drive-virtio-disk0,id=virtio-disk0,bootindex=2 -drive if=none,id
  =drive-ide0-1-0,readonly=on -device ide-cd,bus=ide.1,unit=0,drive
  =drive-ide0-1-0,id=ide0-1-0,bootindex=1 -netdev
  tap,fd=23,id=hostnet0,vhost=on,vhostfd=25 -device virtio-net
  pci,netdev=hostnet0,id=net0,mac=52:54:00:66:2e:0f,bus=pci.0,addr=0x3
  -vnc 0.0.0.0:0 -device cirrus-vga,id=video0,bus=pci.0,addr=0x2 -device
  virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5 -msg timestamp=on

  File system:  zfs v0.6.5.6

  While running: 
  virsh blockcommit test1 vda --active --pivot --verbose

  VM running very heavy IO load

  GDB reporting:

  #0  0x00007fd80132c3f8 in raise () at /lib64/libc.so.6
  #1  0x00007fd80132dffa in abort () at /lib64/libc.so.6
  #2  0x00007fd801324c17 in __assert_fail_base () at /lib64/libc.so.6
  #3  0x00007fd801324cc2 in  () at /lib64/libc.so.6
  #4  0x000055d9918d7572 in bdrv_replace_in_backing_chain (old=0x55d993ed9c10, 
new=0x55d9931ccc10) at block.c:2096
          __PRETTY_FUNCTION__ = "bdrv_replace_in_backing_chain"
  #5  0x000055d991911869 in mirror_exit (job=0x55d993fef830, 
opaque=0x55d999bbefe0) at block/mirror.c:376
          to_replace = 0x55d993ed9c10
          s = 0x55d993fef830
          data = 0x55d999bbefe0
          replace_aio_context = <optimized out>
          src = 0x55d993ed9c10
  #6  0x000055d9918da1dc in block_job_defer_to_main_loop_bh 
(opaque=0x55d9940ce850) at blockjob.c:481
          data = 0x55d9940ce850
          aio_context = 0x55d9931a2610
  #7  0x000055d9918d014b in aio_bh_poll (address@hidden) at async.c:92
          bh = <optimized out>
          bhp = <optimized out>
          next = 0x55d99440f910
          ret = 1
  #8  0x000055d9918dc8c0 in aio_dispatch (ctx=0x55d9931a2610) at aio-posix.c:305
          node = <optimized out>
          progress = false
  #9  0x000055d9918d000e in aio_ctx_dispatch (source=<optimized out>, 
callback=<optimized out>, user_data=<optimized out>) at async.c:231
          ctx = <optimized out>
  #10 0x00007fd8037cf787 in g_main_context_dispatch () at 
/usr/lib64/libglib-2.0.so.0
  #11 0x000055d9918db03b in main_loop_wait () at main-loop.c:211
          context = 0x55d9931a3200
          pfds = <optimized out>
          ret = 0
          spin_counter = 1
          ret = 0
          timeout = 4294967295
          timeout_ns = <optimized out>
  #12 0x000055d9918db03b in main_loop_wait (timeout=<optimized out>) at 
main-loop.c:256
          ret = 0
          spin_counter = 1
          ret = 0
          timeout = 4294967295
          timeout_ns = <optimized out>
  #13 0x000055d9918db03b in main_loop_wait (nonblocking=<optimized out>) at 
main-loop.c:504
          ret = 0
          timeout = 4294967295
          timeout_ns = <optimized out>
  #14 0x000055d991679cc4 in main () at vl.c:1923
          nonblocking = <optimized out>
          last_io = 2
          i = <optimized out>
          snapshot = <optimized out>
          linux_boot = <optimized out>
          initrd_filename = <optimized out>
          kernel_filename = <optimized out>
          kernel_cmdline = <optimized out>
          boot_order = <optimized out>
          boot_once = <optimized out>
          ds = <optimized out>
          cyls = <optimized out>
          heads = <optimized out>
          secs = <optimized out>
          translation = <optimized out>
          hda_opts = <optimized out>
          opts = <optimized out>
          machine_opts = <optimized out>
          icount_opts = <optimized out>
          olist = <optimized out>
          optind = 49
          optarg = 0x7fffc6d27f43 "timestamp=on"
          loadvm = <optimized out>
          machine_class = 0x55d993194d10
          cpu_model = <optimized out>
          vga_model = 0x0
          qtest_chrdev = <optimized out>
          qtest_log = <optimized out>
          pid_file = <optimized out>
          incoming = <optimized out>
          defconfig = <optimized out>
          userconfig = false
          log_mask = <optimized out>
          log_file = <optimized out>
          trace_events = <optimized out>
          trace_file = <optimized out>
          maxram_size = <optimized out>
          ram_slots = <optimized out>
          vmstate_dump_file = <optimized out>
          main_loop_err = 0x0
          err = 0x0
          __func__ = "main"
  #15 0x000055d991679cc4 in main (argc=<optimized out>, argv=<optimized out>, 
envp=<optimized out>) at vl.c:4699
          i = <optimized out>
          snapshot = <optimized out>
          linux_boot = <optimized out>
          initrd_filename = <optimized out>
          kernel_filename = <optimized out>
          kernel_cmdline = <optimized out>
          boot_order = <optimized out>
          boot_once = <optimized out>
          ds = <optimized out>
          cyls = <optimized out>
          heads = <optimized out>
          secs = <optimized out>
          translation = <optimized out>
          hda_opts = <optimized out>
          opts = <optimized out>
          machine_opts = <optimized out>
          icount_opts = <optimized out>
          olist = <optimized out>
          optind = 49
          optarg = 0x7fffc6d27f43 "timestamp=on"
          loadvm = <optimized out>
          machine_class = 0x55d993194d10
          cpu_model = <optimized out>
          vga_model = 0x0
          qtest_chrdev = <optimized out>
          qtest_log = <optimized out>
          pid_file = <optimized out>
          incoming = <optimized out>
          defconfig = <optimized out>
          userconfig = false
          log_mask = <optimized out>
          log_file = <optimized out>
          trace_events = <optimized out>
          trace_file = <optimized out>
          maxram_size = <optimized out>
          ram_slots = <optimized out>
          vmstate_dump_file = <optimized out>
          main_loop_err = 0x0
          err = 0x0
          __func__ = "main"


  I can reproduce this at will, and can provide more information per a
  dev's request.

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