Program received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7f79a8bfe700 (LWP 11306)] 0x00007f79badf323f in virtio_blk_rw_complete (opaque=0x7f79bb9606a0, ret=0) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/hw/block/virtio-blk.c:99 99 bdrv_acct_done(req->dev->bs, &req->acct); (gdb) thread apply all bt Thread 5 (Thread 0x7f79aa753700 (LWP 11302)): #0 0x00007f79b4a87727 in ioctl () from /lib64/libc.so.6 #1 0x00007f79bade24d9 in kvm_vcpu_ioctl (address@hidden, address@hidden) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/kvm-all.c:1845 #2 0x00007f79bade2615 in kvm_cpu_exec (address@hidden) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/kvm-all.c:1714 #3 0x00007f79badcdd2c in qemu_kvm_cpu_thread_fn (arg=0x7f79bba17eb0) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/cpus.c:874 #4 0x00007f79b7589f3a in start_thread () from /lib64/libpthread.so.0 #5 0x00007f79b4a8fc3d in clone () from /lib64/libc.so.6 Thread 4 (Thread 0x7f79a9f52700 (LWP 11303)): #0 0x00007f79b4a87727 in ioctl () from /lib64/libc.so.6 #1 0x00007f79bade24d9 in kvm_vcpu_ioctl (address@hidden, address@hidden) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/kvm-all.c:1845 #2 0x00007f79bade2615 in kvm_cpu_exec (address@hidden) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/kvm-all.c:1714 #3 0x00007f79badcdd2c in qemu_kvm_cpu_thread_fn (arg=0x7f79bba53760) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/cpus.c:874 #4 0x00007f79b7589f3a in start_thread () from /lib64/libpthread.so.0 #5 0x00007f79b4a8fc3d in clone () from /lib64/libc.so.6 Thread 3 (Thread 0x7f79a8bfe700 (LWP 11306)): #0 0x00007f79badf323f in virtio_blk_rw_complete (opaque=0x7f79bb9606a0, ret=0) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/hw/block/virtio-blk.c:99 #1 0x00007f79bb029a62 in bdrv_co_em_bh (opaque=0x7f789400dc30) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/block.c:4666 #2 0x00007f79bb021597 in aio_bh_poll (address@hidden) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/async.c:81 #3 0x00007f79bb032d05 in aio_poll (ctx=0x7f79bba37e90, address@hidden) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/aio-posix.c:188 #4 0x00007f79baea67b7 in iothread_run (opaque=0x7f79bbc18728) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/iothread.c:41 #5 0x00007f79b7589f3a in start_thread () from /lib64/libpthread.so.0 #6 0x00007f79b4a8fc3d in clone () from /lib64/libc.so.6 Thread 2 (Thread 0x7f789b7ff700 (LWP 11307)): #0 0x00007f79b758dd0c in pthread_cond_wait () from /lib64/libpthread.so.0 #1 0x00007f79bb07fcb9 in qemu_cond_wait (address@hidden, address@hidden) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/util/qemu-thread-posix.c:135 #2 0x00007f79bb01c95b in vnc_worker_thread_loop (address@hidden) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/ui/vnc-jobs.c:222 #3 0x00007f79bb01cd30 in vnc_worker_thread (arg=0x7f79bbc17e20) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/ui/vnc-jobs.c:323 #4 0x00007f79b7589f3a in start_thread () from /lib64/libpthread.so.0 #5 0x00007f79b4a8fc3d in clone () from /lib64/libc.so.6 Thread 1 (Thread 0x7f79bac87980 (LWP 11301)): #0 0x00007f79b4a86116 in ppoll () from /lib64/libc.so.6 #1 0x00007f79bb031b19 in ppoll (__ss=0x0, __timeout=0x7fffa40e26e0, __nfds=, __fds=) at /usr/include/bits/poll2.h:77 #2 qemu_poll_ns (fds=, nfds=, address@hidden) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/qemu-timer.c:319 #3 0x00007f79bb030f04 in os_host_main_loop_wait (timeout=510000000) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/main-loop.c:229 #4 main_loop_wait (nonblocking=) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/main-loop.c:484 #5 0x00007f79bad9eb9d in main_loop () at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/vl.c:2010 #6 main (argc=, argv=, envp=) at /var/tmp/portage/app-emulation/qemu-2.1.0/work/qemu-2.1.0/vl.c:4530