Hi all, I got a depressed problem(libvirtd crash with SIGABRT or SIGSEGV sometimes) when attach a nbd disk to a VM by using cmd as follow: virsh attach-disk 228 --source /dev/nbd0 --target vdd --sourcetype block --driver qemu --subdriver raw or just using virsh attach-disk 228 /dev/nbd0 vdd. and this problem occurs everytime when I attach a nbd disk to VM. the device nbd0 is create by qemu-nbd cmd: qemu-nbd -c /dev/nbd0 /home/hzwangpan/zero root@114-113-199-15:/home/hzwangpan# qemu-nbd -V qemu-nbd version 0.0.1 the 'zero' file was created by qemu-img cmd: qemu-img create -f raw zero 512M qemu-img version 1.1.0, Copyright (c) 2004-2008 Fabrice Bellard Some info of packages' version is listed below: root@114-113-199-15:/home/hzwangpan# dpkg -l | grep libvi ii libvirt-bin 0.9.12-4 programs for the libvirt library ii libvirt-dev 0.9.12-4 development files for the libvirt library ii libvirt0 0.9.12-4 library for interfacing with different virtualization systems ii libvirt0-dbg 0.9.12-4 library for interfacing with different virtualization systems root@114-113-199-15:/home/hzwangpan# virsh version Compiled against library: libvir 0.9.12 Using library: libvir 0.9.12 Using API: QEMU 0.9.12 Running hypervisor: QEMU 1.1.0 root@114-113-199-15:/home/hzwangpan# kvm -version QEMU emulator version 1.1.0 (qemu-kvm-1.1.0+dfsg-3, Debian), Copyright (c) 2003-2008 Fabrice Bellard root@114-113-199-15:/home/hzwangpan# uname -a Linux 114-113-199-15 3.2.0-3-amd64 #1 SMP Thu Jun 28 09:07:26 UTC 2012 x86_64 GNU/Linux root@114-113-199-15:/home/hzwangpan# cat /etc/issue Debian GNU/Linux wheezy/sid \n \l the backtrace info when libvirtd crash is list here: 1) one situation: *** glibc detected *** /usr/sbin/libvirtd: malloc(): memory corruption (fast): 0x000000000087bc10 *** ======= Backtrace: ========= /lib/x86_64-linux-gnu/libc.so.6(+0x75b46)[0x7ffff4608b46] /lib/x86_64-linux-gnu/libc.so.6(+0x79428)[0x7ffff460c428] /lib/x86_64-linux-gnu/libc.so.6(__libc_malloc+0x70)[0x7ffff460d960] /lib/x86_64-linux-gnu/libc.so.6(__strdup+0x22)[0x7ffff4612912] /usr/lib/libvirt.so.0(virJSONValueObjectAppend+0x39)[0x7ffff77b75c9] /usr/lib/libvirt.so.0(virJSONValueObjectAppendString+0x37)[0x7ffff77b7e87] /usr/sbin/libvirtd[0x4aa884] /usr/sbin/libvirtd[0x4ac3a7] /usr/sbin/libvirtd[0x49d303] /usr/sbin/libvirtd[0x4a8bfe] /usr/sbin/libvirtd[0x4b0814] /usr/sbin/libvirtd[0x484a5d] /usr/sbin/libvirtd[0x461d9e] /usr/lib/libvirt.so.0(virDomainAttachDevice+0xdd)[0x7ffff7846f5d] /usr/sbin/libvirtd[0x43ccfe] /usr/lib/libvirt.so.0(+0x129866)[0x7ffff788a866] /usr/lib/libvirt.so.0(+0x1254d1)[0x7ffff78864d1] /usr/lib/libvirt.so.0(+0x6273e)[0x7ffff77c373e] /usr/lib/libvirt.so.0(+0x621c9)[0x7ffff77c31c9] /lib/x86_64-linux-gnu/libpthread.so.0(+0x6b50)[0x7ffff4d27b50] /lib/x86_64-linux-gnu/libc.so.6(clone+0x6d)[0x7ffff466b6dd] ======= Memory map: ======== 00400000-0053d000 r-xp 00000000 08:01 69457 /usr/sbin/libvirtd 0073c000-0073e000 r--p 0013c000 08:01 69457 /usr/sbin/libvirtd 0073e000-00746000 rw-p 0013e000 08:01 69457 /usr/sbin/libvirtd 00746000-00aa1000 rw-p 00000000 00:00 0 [heap] 7fffe0000000-7fffe021f000 rw-p 00000000 00:00 0 7fffe021f000-7fffe4000000 ---p 00000000 00:00 0 7fffe77ff000-7fffe7800000 ---p 00000000 00:00 0 7fffe7800000-7fffe8000000 rw-p 00000000 00:00 0 7fffe8000000-7fffe8175000 rw-p 00000000 00:00 0 7fffe8175000-7fffec000000 ---p 00000000 00:00 0 7fffec138000-7fffec139000 ---p 00000000 00:00 0 7fffec139000-7fffec939000 rw-p 00000000 00:00 0 7fffec939000-7fffec96e000 r--s 00000000 08:06 286722 /var/cache/nscd/passwd 7fffec96e000-7fffec99a000 rw-p 00000000 00:00 0 7fffec99a000-7fffec99b000 ---p 00000000 00:00 0 7fffec99b000-7fffed19b000 rw-p 00000000 00:00 0 7fffed19b000-7fffed315000 r-xp 00000000 08:01 124989 /usr/lib/x86_64-linux-gnu/libdb-5.1.so 7fffed315000-7fffed515000 ---p 0017a000 08:01 124989 /usr/lib/x86_64-linux-gnu/libdb-5.1.so 7fffed515000-7fffed51b000 r--p 0017a000 08:01 124989 /usr/lib/x86_64-linux-gnu/libdb-5.1.so 7fffed51b000-7fffed51e000 rw-p 00180000 08:01 124989 /usr/lib/x86_64-linux-gnu/libdb-5.1.so 7fffed51e000-7fffed524000 r-xp 00000000 08:01 133549 /usr/lib/x86_64-linux-gnu/sasl2/libsasldb.so.2.0.25 7fffed524000-7fffed723000 ---p 00006000 08:01 133549 /usr/lib/x86_64-linux-gnu/sasl2/libsasldb.so.2.0.25 7fffed723000-7fffed724000 r--p 00005000 08:01 133549 /usr/lib/x86_64-linux-gnu/sasl2/libsasldb.so.2.0.25 7fffed724000-7fffed725000 rw-p 00006000 08:01 133549 /usr/lib/x86_64-linux-gnu/sasl2/libsasldb.so.2.0.25 7fffed725000-7fffed75a000 r--s 00000000 08:06 286723 /var/cache/nscd/group 7fffed75a000-7fffed75b000 ---p 00000000 00:00 0 7fffed75b000-7fffedf5b000 rw-p 00000000 00:00 0 7fffedf5b000-7fffedf5c000 ---p 00000000 00:00 0 7fffedf5c000-7fffee75c000 rw-p 00000000 00:00 0 7fffee75c000-7fffee75d000 ---p 00000000 00:00 0 7fffee75d000-7fffeef5d000 rw-p 00000000 00:00 0 7fffeef5d000-7fffeef5e000 ---p 00000000 00:00 0 7fffeef5e000-7fffef75e000 rw-p 00000000 00:00 0 7fffef75e000-7fffef75f000 ---p 00000000 00:00 0 7fffef75f000-7fffeff5f000 rw-p 00000000 00:00 0 7fffeff5f000-7fffeff60000 ---p 00000000 00:00 0 7fffeff60000-7ffff0760000 rw-p 00000000 00:00 0 7ffff0760000-7ffff0761000 ---p 00000000 00:00 0 7ffff0761000-7ffff0f61000 rw-p 00000000 00:00 0 7ffff0f61000-7ffff0f62000 ---p 00000000 00:00 0 7ffff0f62000-7ffff1762000 rw-p 00000000 00:00 0 7ffff1762000-7ffff1763000 ---p 00000000 00:00 0 7ffff1763000-7ffff1f63000 rw-p 00000000 00:00 0 7ffff1f63000-7ffff1f64000 ---p 00000000 00:00 0 7ffff1f64000-7ffff2764000 rw-p 00000000 00:00 0 7ffff2764000-7ffff2799000 r--s 00000000 08:06 303114 /var/cache/nscd/hosts 7ffff2799000-7ffff27ae000 r-xp 00000000 08:01 57404 /lib/x86_64-linux-gnu/libgcc_s.so.1 7ffff27ae000-7ffff29ae000 ---p 00015000 08:01 57404 /lib/x86_64-linux-gnu/libgcc_s.so.1 7ffff29ae000-7ffff29af000 rw-p 00015000 08:01 57404 /lib/x86_64-linux-gnu/libgcc_s.so.1 7ffff29af000-7ffff29c7000 r-xp 00000000 08:01 110124 /usr/lib/libfa.so.1.3.5 7ffff29c7000-7ffff2bc7000 ---p 00018000 08:01 110124 /usr/lib/libfa.so.1.3.5 7ffff2bc7000-7ffff2bc8000 rw-p 00018000 08:01 110124 /usr/lib/libfa.so.1.3.5 7ffff2bc8000-7ffff2be9000 r-xp 00000000 08:01 57814 /lib/x86_64-linux-gnu/liblzma.so.5.0.0 7ffff2be9000-7ffff2de9000 ---p 00021000 08:01 57814 /lib/x86_64-linux-gnu/liblzma.so.5.0.0 7ffff2de9000-7ffff2dea000 r--p 00021000 08:01 57814 /lib/x86_64-linux-gnu/liblzma.so.5.0.0 7ffff2dea000-7ffff2deb000 rw-p 00022000 08:01 57814 /lib/x86_64-linux-gnu/liblzma.so.5.0.0 7ffff2deb000-7ffff2e6c000 r-xp 00000000 08:01 57526 /lib/x86_64-linux-gnu/libm-2.13.so 7ffff2e6c000-7ffff306b000 ---p 00081000 08:01 57526 /lib/x86_64-linux-gnu/libm-2.13.so 7ffff306b000-7ffff306c000 r--p 00080000 08:01 57526 /lib/x86_64-linux-gnu/libm-2.13.so 7ffff306c000-7ffff306d000 rw-p 00081000 08:01 57526 /lib/x86_64-linux-gnu/libm-2.13.so 7ffff306d000-7ffff30a9000 r-xp 00000000 08:01 76972 /usr/lib/x86_64-linux-gnu/libxslt.so.1.1.26 7ffff30a9000-7ffff32a8000 ---p 0003c000 08:01 76972 /usr/lib/x86_64-linux-gnu/libxslt.so.1.1.26 7ffff32a8000-7ffff32aa000 r--p 0003b000 08:01 76972 /usr/lib/x86_64-linux-gnu/libxslt.so.1.1.26 7ffff32aa000-7ffff32ab000 rw-p 0003d000 08:01 76972 /usr/lib/x86_64-linux-gnu/libxslt.so.1.1.26 7ffff32ab000-7ffff32bf000 r-xp 00000000 08:01 76971 /usr/lib/x86_64-linux-gnu/libexslt.so.0.8.15 7ffff32bf000-7ffff34be000 ---p 00014000 08:01 76971 /usr/lib/x86_64-linux-gnu/libexslt.so.0.8.15 7ffff34be000-7ffff34bf000 r--p 00013000 08:01 76971 /usr/lib/x86_64-linux-gnu/libexslt.so.0.8.15 7ffff34bf000-7ffff34c0000 rw-p 00014000 08:01 76971 /usr/lib/x86_64-linux-gnu/libexslt.so.0.8.15 7ffff34c0000-7ffff3519000 r-xp 00000000 08:01 93870 /usr/lib/libaugeas.so.0.15.0 7ffff3519000-7ffff3718000 ---p 00059000 08:01 93870 /usr/lib/libaugeas.so.0.15.0 7ffff3718000-7ffff371b000 rw-p 00058000 08:01 93870 /usr/lib/libaugeas.so.0.15.0 7ffff371b000-7ffff372e000 r-xp 00000000 08:01 57421 /lib/x86_64-linux-gnu/libresolv-2.13.so Program received signal SIGABRT, Aborted. [Switching to Thread 0x7ffff1761700 (LWP 8216)] 0x00007ffff45c5475 in raise () from /lib/x86_64-linux-gnu/libc.so.6 (gdb) bt #0 0x00007ffff45c5475 in raise () from /lib/x86_64-linux-gnu/libc.so.6 #1 0x00007ffff45c86f0 in abort () from /lib/x86_64-linux-gnu/libc.so.6 #2 0x00007ffff45ff2fb in ?? () from /lib/x86_64-linux-gnu/libc.so.6 #3 0x00007ffff4608b46 in ?? () from /lib/x86_64-linux-gnu/libc.so.6 #4 0x00007ffff460c428 in ?? () from /lib/x86_64-linux-gnu/libc.so.6 #5 0x00007ffff460d960 in malloc () from /lib/x86_64-linux-gnu/libc.so.6 #6 0x00007ffff4612912 in strdup () from /lib/x86_64-linux-gnu/libc.so.6 #7 0x00007ffff77b75c9 in virJSONValueObjectAppend (object=object@entry=0x91d810, key=key@entry=0x4fef81 "execute", value=value@entry=0x85de90) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/util/json.c:274 #8 0x00007ffff77b7e87 in virJSONValueObjectAppendString (object=object@entry=0x91d810, key=key@entry=0x4fef81 "execute", value=value@entry=0x51196f "human-monitor-command") at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/util/json.c:296 #9 0x00000000004aa884 in qemuMonitorJSONMakeCommandRaw (wrap=wrap@entry=false, cmdname=cmdname@entry=0x51196f "human-monitor-command") at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_monitor_json.c:404 #10 0x00000000004ac3a7 in qemuMonitorJSONHumanCommandWithFd (mon=mon@entry=0x7fffe80010b0, cmd_str=<optimized out>, scm_fd=-1, reply_str=0x7ffff1760920) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_monitor_json.c:886 #11 0x000000000049d303 in qemuMonitorHMPCommandWithFd (mon=mon@entry=0x7fffe80010b0, cmd=<optimized out>, scm_fd=scm_fd@entry=-1, reply=reply@entry=0x7ffff1760920) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_monitor.c:910 #12 0x00000000004a8bfe in qemuMonitorTextAddDrive (mon=mon@entry=0x7fffe80010b0, drivestr=drivestr@entry=0x7fffe0202020 "file=/dev/nbd0,if=none,id=drive-virtio-disk3,format=raw") at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_monitor_text.c:2836 #13 0x00000000004b0814 in qemuMonitorJSONAddDrive (mon=0x7fffe80010b0, drivestr=0x7fffe0202020 "file=/dev/nbd0,if=none,id=drive-virtio-disk3,format=raw") at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_monitor_json.c:2979 #14 0x00000000004a1bad in qemuMonitorAddDrive (mon=<optimized out>, drivestr=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_monitor.c:2571 #15 0x0000000000484a5d in qemuDomainAttachPciDiskDevice (conn=conn@entry=0x7fffe00111f0, driver=driver@entry=0x81fec0, vm=vm@entry=0x82f6b0, disk=disk@entry=0x7fffe02024d0) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_hotplug.c:250 #16 0x0000000000461d9e in qemuDomainAttachDeviceDiskLive (vm=0x82f6b0, driver=0x81fec0, conn=0x7fffe00111f0, dev=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_driver.c:5179 #17 qemuDomainAttachDeviceLive (dev=0x7fffe001d5b0, vm=0x82f6b0, dom=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_driver.c:5238 #18 qemuDomainModifyDeviceFlags (dom=<optimized out>, xml=0x7fffe001d5b0 "\001", flags=<optimized out>, action=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_driver.c:5779 #19 0x00007ffff7846f5d in virDomainAttachDevice (domain=domain@entry=0x7fffe0201fb0, xml=0x7fffe0201e50 "<disk type='block'>\n <driver name='qemu' type='raw'/>\n <source dev='/dev/nbd0'/>\n <target dev='vdd'/>\n</disk>\n") at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/libvirt.c:9288 #20 0x000000000043ccfe in remoteDispatchDomainAttachDevice (args=0x7fffe0201ff0, rerr=0x7ffff1760c90, client=<optimized out>, server=<optimized out>, msg=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./daemon/remote_dispatch.h:320 #21 remoteDispatchDomainAttachDeviceHelper (server=<optimized out>, client=<optimized out>, msg=<optimized out>, rerr=0x7ffff1760c90, args=0x7fffe0201ff0, ret=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./daemon/remote_dispatch.h:298 #22 0x00007ffff788a866 in virNetServerProgramDispatchCall (msg=0x7fffe8093d20, client=0x7fffe8053050, server=0x76e920, prog=0x778880) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/rpc/virnetserverprogram.c:416 #23 virNetServerProgramDispatch (prog=0x778880, server=server@entry=0x76e920, client=0x7fffe8053050, msg=0x7fffe8093d20) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/rpc/virnetserverprogram.c:289 #24 0x00007ffff78864d1 in virNetServerHandleJob (jobOpaque=<optimized out>, opaque=0x76e920) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/rpc/virnetserver.c:161 #25 0x00007ffff77c373e in virThreadPoolWorker (opaque=opaque@entry=0x7789a0) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/util/threadpool.c:144 #26 0x00007ffff77c31c9 in virThreadHelper (data=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/util/threads-pthread.c:161 #27 0x00007ffff4d27b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0 #28 0x00007ffff466b6dd in clone () from /lib/x86_64-linux-gnu/libc.so.6 #29 0x0000000000000000 in ?? () (gdb) f 7 #7 0x00007ffff77b75c9 in virJSONValueObjectAppend (object=object@entry=0x91d810, key=key@entry=0x4fef81 "execute", value=value@entry=0x85de90) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/util/json.c:274 warning: Source file is more recent than executable. 274 if (!(newkey = strdup(key))) (gdb) l 269 return -1; 270 271 if (virJSONValueObjectHasKey(object, key)) 272 return -1; 273 274 if (!(newkey = strdup(key))) 275 return -1; 276 277 if (VIR_REALLOC_N(object->data.object.pairs, 278 object->data.object.npairs + 1) < 0) { (gdb) 2) another situation: Program received signal SIGABRT, Aborted. [Switching to Thread 0x7ffff075f700 (LWP 11697)] 0x00007ffff45c5475 in raise () from /lib/x86_64-linux-gnu/libc.so.6 (gdb) bt #0 0x00007ffff45c5475 in raise () from /lib/x86_64-linux-gnu/libc.so.6 #1 0x00007ffff45c86f0 in abort () from /lib/x86_64-linux-gnu/libc.so.6 #2 0x00007ffff45ff2fb in ?? () from /lib/x86_64-linux-gnu/libc.so.6 #3 0x00007ffff4608b46 in ?? () from /lib/x86_64-linux-gnu/libc.so.6 #4 0x00007ffff460d87c in free () from /lib/x86_64-linux-gnu/libc.so.6 #5 0x00007ffff77ba4c9 in virFree (ptrptr=ptrptr@entry=0x7ffff075e8e8) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/util/memory.c:310 #6 0x000000000049d321 in qemuMonitorHMPCommandWithFd (mon=mon@entry=0x9214e0, cmd=<optimized out>, scm_fd=scm_fd@entry=-1, reply=reply@entry=0x7ffff075e920) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_monitor.c:916 #7 0x00000000004a8bfe in qemuMonitorTextAddDrive (mon=mon@entry=0x9214e0, drivestr=drivestr@entry=0x8f7090 "file=/dev/nbd0,if=none,id=drive-virtio-disk3,format=raw") at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_monitor_text.c:2836 #8 0x00000000004b0814 in qemuMonitorJSONAddDrive (mon=0x9214e0, drivestr=0x8f7090 "file=/dev/nbd0,if=none,id=drive-virtio-disk3,format=raw") at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_monitor_json.c:2979 #9 0x00000000004a1bad in qemuMonitorAddDrive (mon=<optimized out>, drivestr=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_monitor.c:2571 #10 0x0000000000484a5d in qemuDomainAttachPciDiskDevice (conn=conn@entry=0x9213c0, driver=driver@entry=0x8162c0, vm=vm@entry=0x820530, disk=disk@entry=0x8f5290) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_hotplug.c:250 #11 0x0000000000461d9e in qemuDomainAttachDeviceDiskLive (vm=0x820530, driver=0x8162c0, conn=0x9213c0, dev=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_driver.c:5179 #12 qemuDomainAttachDeviceLive (dev=0x8465b0, vm=0x820530, dom=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_driver.c:5238 #13 qemuDomainModifyDeviceFlags (dom=<optimized out>, xml=0x8465b0 "\001", flags=<optimized out>, action=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_driver.c:5779 #14 0x00007ffff7846f5d in virDomainAttachDevice (domain=domain@entry=0x8f6080, xml=0x8f5610 "<disk type='block'>\n <driver name='qemu' type='raw'/>\n <source dev='/dev/nbd0'/>\n <target dev='vdd'/>\n</disk>\n") at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/libvirt.c:9288 #15 0x000000000043ccfe in remoteDispatchDomainAttachDevice (args=0x8f60c0, rerr=0x7ffff075ec90, client=<optimized out>, server=<optimized out>, msg=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./daemon/remote_dispatch.h:320 #16 remoteDispatchDomainAttachDeviceHelper (server=<optimized out>, client=<optimized out>, msg=<optimized out>, rerr=0x7ffff075ec90, args=0x8f60c0, ret=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./daemon/remote_dispatch.h:298 #17 0x00007ffff788a866 in virNetServerProgramDispatchCall (msg=0x7fffe00929d0, client=0x7fffe0052880, server=0x76e920, prog=0x778880) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/rpc/virnetserverprogram.c:416 #18 virNetServerProgramDispatch (prog=0x778880, server=server@entry=0x76e920, client=0x7fffe0052880, msg=0x7fffe00929d0) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/rpc/virnetserverprogram.c:289 #19 0x00007ffff78864d1 in virNetServerHandleJob (jobOpaque=<optimized out>, opaque=0x76e920) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/rpc/virnetserver.c:161 #20 0x00007ffff77c373e in virThreadPoolWorker (opaque=opaque@entry=0x7789a0) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/util/threadpool.c:144 #21 0x00007ffff77c31c9 in virThreadHelper (data=<optimized out>) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/util/threads-pthread.c:161 #22 0x00007ffff4d27b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0 #23 0x00007ffff466b6dd in clone () from /lib/x86_64-linux-gnu/libc.so.6 #24 0x0000000000000000 in ?? () (gdb) f 6 #6 0x000000000049d321 in qemuMonitorHMPCommandWithFd (mon=mon@entry=0x9214e0, cmd=<optimized out>, scm_fd=scm_fd@entry=-1, reply=reply@entry=0x7ffff075e920) at /build/buildd-libvirt_0.9.12-4-amd64-KyxbcZ/libvirt-0.9.12/./src/qemu/qemu_monitor.c:916 916 VIR_FREE(json_cmd); (gdb) l 911 } else { 912 ret = qemuMonitorTextCommandWithFd(mon, cmd, scm_fd, reply); 913 } 914 915 cleanup: 916 VIR_FREE(json_cmd); 917 return ret; 918 } 919 920 /* Ensure proper locking around callbacks. */ (gdb) p json_cmd $3 = 0x933c20 "drive_add dummy file=/dev/nbd0,if=none,id=drive-virtio-disk3,format=raw" (gdb) anybody can give me any clue? Thanks in advance! 2012-08-16 Wangpan