<div dir="ltr">i did the debugging as you said. Kindly refer the following logs:<div><br></div><div><div>(gdb) c</div><div>Continuing.</div><div>thread apply all bt</div><div>[New Thread 0x7fc337c6b700 (LWP 29520)]</div><div>
<br></div><div>Program received signal SIGSEGV, Segmentation fault.</div><div>0x0000000000000000 in ?? ()</div><div>(gdb) thread apply all bt</div><div><br></div><div>Thread 12 (Thread 0x7fc337c6b700 (LWP 29520)):</div><div>
#0 0x00007fc33509f18d in read () from /lib/x86_64-linux-gnu/libpthread.so.0</div><div>#1 0x00007fc32b1555c4 in read_all (fd=26, data=0x7fc3380e0a70, data@entry=0x20, len=len@entry=16, nonblocking=nonblocking@entry=0) at xs.c:365</div>
<div>#2 0x00007fc32b1556d8 in read_message (h=h@entry=0x7fc324013ee0, nonblocking=nonblocking@entry=0) at xs.c:1071</div><div>#3 0x00007fc32b156005 in read_thread (arg=0x7fc324013ee0) at xs.c:1137</div><div>#4 0x00007fc335097b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0</div>
<div>#5 0x00007fc3349daa3d in clone () from /lib/x86_64-linux-gnu/libc.so.6</div><div>#6 0x0000000000000000 in ?? ()</div><div><br></div><div>Thread 11 (Thread 0x7fc330e7f700 (LWP 29170)):</div><div>#0 0x00007fc33509c2d4 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/x86_64-linux-gnu/libpthread.so.0</div>
<div>#1 0x00007fc3371ae9ea in virCondWait (c=c@entry=0x7fc3380dbd80, m=m@entry=0x7fc3380dbd58) at util/virthreadpthread.c:117</div><div>#2 0x00007fc3371af0cb in virThreadPoolWorker (opaque=opaque@entry=0x7fc3380db870) at util/virthreadpool.c:103</div>
<div>#3 0x00007fc3371ae686 in virThreadHelper (data=<optimized out>) at util/virthreadpthread.c:161</div><div>#4 0x00007fc335097b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0</div><div>#5 0x00007fc3349daa3d in clone () from /lib/x86_64-linux-gnu/libc.so.6</div>
<div>#6 0x0000000000000000 in ?? ()</div><div><br></div><div>Thread 10 (Thread 0x7fc33067e700 (LWP 29171)):</div><div>#0 0x00007fc33509c2d4 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/x86_64-linux-gnu/libpthread.so.0</div>
<div>#1 0x00007fc3371ae9ea in virCondWait (c=c@entry=0x7fc3380dbd80, m=m@entry=0x7fc3380dbd58) at util/virthreadpthread.c:117</div><div>#2 0x00007fc3371af0cb in virThreadPoolWorker (opaque=opaque@entry=0x7fc3380db640) at util/virthreadpool.c:103</div>
<div>#3 0x00007fc3371ae686 in virThreadHelper (data=<optimized out>) at util/virthreadpthread.c:161</div><div>#4 0x00007fc335097b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0</div><div>#5 0x00007fc3349daa3d in clone () from /lib/x86_64-linux-gnu/libc.so.6</div>
<div>#6 0x0000000000000000 in ?? ()</div><div><br></div><div>Thread 9 (Thread 0x7fc32fe7d700 (LWP 29172)):</div><div>#0 0x00007fc33509c2d4 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/x86_64-linux-gnu/libpthread.so.0</div>
<div>#1 0x00007fc3371ae9ea in virCondWait (c=c@entry=0x7fc3380dbd80, m=m@entry=0x7fc3380dbd58) at util/virthreadpthread.c:117</div><div>#2 0x00007fc3371af0cb in virThreadPoolWorker (opaque=opaque@entry=0x7fc3380db870) at util/virthreadpool.c:103</div>
<div>#3 0x00007fc3371ae686 in virThreadHelper (data=<optimized out>) at util/virthreadpthread.c:161</div><div>#4 0x00007fc335097b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0</div><div>#5 0x00007fc3349daa3d in clone () from /lib/x86_64-linux-gnu/libc.so.6</div>
<div>#6 0x0000000000000000 in ?? ()</div><div><br></div><div>Thread 8 (Thread 0x7fc32f67c700 (LWP 29173)):</div><div>#0 0x00007fc33497cb9f in realloc () from /lib/x86_64-linux-gnu/libc.so.6</div><div>#1 0x00007fc3349eec85 in __vasprintf_chk () from /lib/x86_64-linux-gnu/libc.so.6</div>
<div>---Type <return> to continue, or q <return> to quit---</div><div>#2 0x00007fc3371aac0a in vasprintf (__ap=0x7fc32f67b6d0, __fmt=0x7fc337391017 "%llu: %s : %s:%d : %s\n", __ptr=0x7fc32f67b830)</div>
<div> at /usr/include/x86_64-linux-gnu/bits/stdio2.h:199</div><div>#3 virVasprintfInternal (report=report@entry=false, domcode=0, filename=0x0, funcname=0x0, linenr=0, strp=0x7fc32f67b830, </div><div> fmt=fmt@entry=0x7fc337391017 "%llu: %s : %s:%d : %s\n", list=list@entry=0x7fc32f67b6d0) at util/virstring.c:337</div>
<div>#4 0x00007fc3371aad1b in virAsprintfInternal (report=report@entry=false, domcode=domcode@entry=0, filename=filename@entry=0x0, funcname=funcname@entry=0x0, </div><div> linenr=linenr@entry=0, strp=strp@entry=0x7fc32f67b830, fmt=fmt@entry=0x7fc337391017 "%llu: %s : %s:%d : %s\n") at util/virstring.c:358</div>
<div>#5 0x00007fc33718cb59 in virLogFormatString (str=<optimized out>, priority=VIR_LOG_DEBUG, funcname=0x7fc337394734 "virObjectRef", linenr=293, msg=0x7fc32f67b830)</div><div> at util/virlog.c:719</div>
<div>#6 virLogVMessage (source=VIR_LOG_FROM_TRACE, priority=VIR_LOG_DEBUG, filename=0x7fc337394597 "util/virobject.c", linenr=293, funcname=0x7fc337394734 "virObjectRef", </div><div> metadata=0x0, fmt=fmt@entry=0x7fc3373945f1 "OBJECT_REF: obj=%p", vargs=vargs@entry=0x7fc32f67b8c0) at util/virlog.c:846</div>
<div>#7 0x00007fc33718cfc7 in virLogMessage (source=source@entry=VIR_LOG_FROM_TRACE, priority=priority@entry=VIR_LOG_DEBUG, </div><div> filename=filename@entry=0x7fc337394597 "util/virobject.c", linenr=linenr@entry=293, funcname=funcname@entry=0x7fc337394734 "virObjectRef", </div>
<div> metadata=metadata@entry=0x0, fmt=fmt@entry=0x7fc3373945f1 "OBJECT_REF: obj=%p") at util/virlog.c:778</div><div>#8 0x00007fc33719c3d7 in virObjectRef (anyobj=0x7fc338102720) at util/virobject.c:293</div>
<div>#9 0x00007fc32af1824f in libxlDriverConfigGet (driver=driver@entry=0x7fc338108930) at libxl/libxl_conf.c:1124</div><div>#10 0x00007fc32af1a50e in libxlVmCleanup (driver=driver@entry=0x7fc338108930, vm=vm@entry=0x7fc32400f530, reason=reason@entry=VIR_DOMAIN_SHUTOFF_DESTROYED)</div>
<div> at libxl/libxl_driver.c:264</div><div>#11 0x00007fc32af20274 in libxlVmReap (driver=0x7fc338108930, vm=0x7fc32400f530, reason=VIR_DOMAIN_SHUTOFF_DESTROYED) at libxl/libxl_driver.c:338</div><div>#12 0x00007fc32af207de in libxlDomainDestroyFlags (dom=0x7fc3380e3770, flags=<optimized out>) at libxl/libxl_driver.c:1507</div>
<div>#13 0x00007fc33723cd37 in virDomainDestroy (domain=domain@entry=0x7fc3380e3770) at libvirt.c:2342</div><div>#14 0x00007fc337cb9ba4 in remoteDispatchDomainDestroy (args=<optimized out>, rerr=0x7fc32f67bcd0, client=0x7fc32400ee60, server=<optimized out>, msg=<optimized out>)</div>
<div> at remote_dispatch.h:3165</div><div>#15 remoteDispatchDomainDestroyHelper (server=<optimized out>, client=0x7fc32400ee60, msg=<optimized out>, rerr=0x7fc32f67bcd0, args=<optimized out>, </div><div>
ret=<optimized out>) at remote_dispatch.h:3143</div><div>#16 0x00007fc3372b4d79 in virNetServerProgramDispatchCall (msg=0x7fc324014070, client=0x7fc32400ee60, server=0x7fc3380dbba0, prog=0x7fc324007750)</div><div>
at rpc/virnetserverprogram.c:435</div><div>#17 virNetServerProgramDispatch (prog=0x7fc324007750, server=server@entry=0x7fc3380dbba0, client=0x7fc32400ee60, msg=0x7fc324014070) at rpc/virnetserverprogram.c:305</div><div>
#18 0x00007fc3372aea78 in virNetServerProcessMsg (msg=<optimized out>, prog=<optimized out>, client=<optimized out>, srv=0x7fc3380dbba0) at rpc/virnetserver.c:165</div><div>#19 virNetServerHandleJob (jobOpaque=<optimized out>, opaque=0x7fc3380dbba0) at rpc/virnetserver.c:186</div>
<div>#20 0x00007fc3371af02e in virThreadPoolWorker (opaque=opaque@entry=0x7fc3380db640) at util/virthreadpool.c:144</div><div>#21 0x00007fc3371ae686 in virThreadHelper (data=<optimized out>) at util/virthreadpthread.c:161</div>
<div>#22 0x00007fc335097b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0</div><div>#23 0x00007fc3349daa3d in clone () from /lib/x86_64-linux-gnu/libc.so.6</div><div>#24 0x0000000000000000 in ?? ()</div><div>
<br></div><div>Thread 7 (Thread 0x7fc32ee7b700 (LWP 29174)):</div><div>#0 0x00007fc33509c2d4 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/x86_64-linux-gnu/libpthread.so.0</div><div>#1 0x00007fc3371ae9ea in virCondWait (c=c@entry=0x7fc3380dbd80, m=m@entry=0x7fc3380dbd58) at util/virthreadpthread.c:117</div>
<div>#2 0x00007fc3371af0cb in virThreadPoolWorker (opaque=opaque@entry=0x7fc3380db870) at util/virthreadpool.c:103</div><div>#3 0x00007fc3371ae686 in virThreadHelper (data=<optimized out>) at util/virthreadpthread.c:161</div>
<div>---Type <return> to continue, or q <return> to quit---</div><div>#4 0x00007fc335097b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0</div><div>#5 0x00007fc3349daa3d in clone () from /lib/x86_64-linux-gnu/libc.so.6</div>
<div>#6 0x0000000000000000 in ?? ()</div><div><br></div><div>Thread 6 (Thread 0x7fc32e67a700 (LWP 29175)):</div><div>#0 0x00007fc33509c2d4 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/x86_64-linux-gnu/libpthread.so.0</div>
<div>#1 0x00007fc3371ae9ea in virCondWait (c=c@entry=0x7fc3380dbe18, m=m@entry=0x7fc3380dbd58) at util/virthreadpthread.c:117</div><div>#2 0x00007fc3371af0eb in virThreadPoolWorker (opaque=opaque@entry=0x7fc3380db640) at util/virthreadpool.c:103</div>
<div>#3 0x00007fc3371ae686 in virThreadHelper (data=<optimized out>) at util/virthreadpthread.c:161</div><div>#4 0x00007fc335097b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0</div><div>#5 0x00007fc3349daa3d in clone () from /lib/x86_64-linux-gnu/libc.so.6</div>
<div>#6 0x0000000000000000 in ?? ()</div><div><br></div><div>Thread 5 (Thread 0x7fc32de79700 (LWP 29176)):</div><div>#0 0x00007fc33509c2d4 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/x86_64-linux-gnu/libpthread.so.0</div>
<div>#1 0x00007fc3371ae9ea in virCondWait (c=c@entry=0x7fc3380dbe18, m=m@entry=0x7fc3380dbd58) at util/virthreadpthread.c:117</div><div>#2 0x00007fc3371af0eb in virThreadPoolWorker (opaque=opaque@entry=0x7fc3380db870) at util/virthreadpool.c:103</div>
<div>#3 0x00007fc3371ae686 in virThreadHelper (data=<optimized out>) at util/virthreadpthread.c:161</div><div>#4 0x00007fc335097b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0</div><div>#5 0x00007fc3349daa3d in clone () from /lib/x86_64-linux-gnu/libc.so.6</div>
<div>#6 0x0000000000000000 in ?? ()</div><div><br></div><div>Thread 4 (Thread 0x7fc32d678700 (LWP 29177)):</div><div>#0 0x00007fc33509c2d4 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/x86_64-linux-gnu/libpthread.so.0</div>
<div>#1 0x00007fc3371ae9ea in virCondWait (c=c@entry=0x7fc3380dbe18, m=m@entry=0x7fc3380dbd58) at util/virthreadpthread.c:117</div><div>#2 0x00007fc3371af0eb in virThreadPoolWorker (opaque=opaque@entry=0x7fc3380db640) at util/virthreadpool.c:103</div>
<div>#3 0x00007fc3371ae686 in virThreadHelper (data=<optimized out>) at util/virthreadpthread.c:161</div><div>#4 0x00007fc335097b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0</div><div>#5 0x00007fc3349daa3d in clone () from /lib/x86_64-linux-gnu/libc.so.6</div>
<div>#6 0x0000000000000000 in ?? ()</div><div><br></div><div>Thread 3 (Thread 0x7fc32ce77700 (LWP 29178)):</div><div>#0 0x00007fc33509c2d4 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/x86_64-linux-gnu/libpthread.so.0</div>
<div>#1 0x00007fc3371ae9ea in virCondWait (c=c@entry=0x7fc3380dbe18, m=m@entry=0x7fc3380dbd58) at util/virthreadpthread.c:117</div><div>#2 0x00007fc3371af0eb in virThreadPoolWorker (opaque=opaque@entry=0x7fc3380db870) at util/virthreadpool.c:103</div>
<div>#3 0x00007fc3371ae686 in virThreadHelper (data=<optimized out>) at util/virthreadpthread.c:161</div><div>#4 0x00007fc335097b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0</div><div>#5 0x00007fc3349daa3d in clone () from /lib/x86_64-linux-gnu/libc.so.6</div>
<div>#6 0x0000000000000000 in ?? ()</div><div><br></div><div>---Type <return> to continue, or q <return> to quit---</div><div>Thread 2 (Thread 0x7fc32c676700 (LWP 29179)):</div><div>#0 0x00007fc33509c2d4 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/x86_64-linux-gnu/libpthread.so.0</div>
<div>#1 0x00007fc3371ae9ea in virCondWait (c=c@entry=0x7fc3380dbe18, m=m@entry=0x7fc3380dbd58) at util/virthreadpthread.c:117</div><div>#2 0x00007fc3371af0eb in virThreadPoolWorker (opaque=opaque@entry=0x7fc3380db640) at util/virthreadpool.c:103</div>
<div>#3 0x00007fc3371ae686 in virThreadHelper (data=<optimized out>) at util/virthreadpthread.c:161</div><div>#4 0x00007fc335097b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0</div><div>#5 0x00007fc3349daa3d in clone () from /lib/x86_64-linux-gnu/libc.so.6</div>
<div>#6 0x0000000000000000 in ?? ()</div><div><br></div><div>Thread 1 (Thread 0x7fc337c4d7c0 (LWP 29169)):</div><div>#0 0x0000000000000000 in ?? ()</div><div>#1 0x00007fc32ace881e in libxl_osevent_occurred_timeout (ctx=<optimized out>, for_libxl=0x7fc3380edf38) at libxl_event.c:1039</div>
<div>#2 0x00007fc32af199c7 in libxlDomainObjTimerCallback (timer=<optimized out>, timer_info=0x7fc3380e3310) at libxl/libxl_domain.c:216</div><div>#3 0x00007fc33717cf7d in virEventPollDispatchTimeouts () at util/vireventpoll.c:451</div>
<div>#4 virEventPollRunOnce () at util/vireventpoll.c:644</div><div>#5 0x00007fc33717b70b in virEventRunDefaultImpl () at util/virevent.c:274</div><div>#6 0x00007fc3372b0065 in virNetServerRun (srv=0x7fc3380dbba0) at rpc/virnetserver.c:1112</div>
<div>#7 0x00007fc337c9851c in main (argc=<optimized out>, argv=<optimized out>) at libvirtd.c:1513</div><div>(gdb) </div><div>(gdb) </div></div><div><br></div><div>****</div><div><br></div><div>regards,</div>
<div>cooldharma06.</div></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Thu, Dec 19, 2013 at 3:30 PM, Daniel P. Berrange <span dir="ltr"><<a href="mailto:berrange@redhat.com" target="_blank">berrange@redhat.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="im">On Thu, Dec 19, 2013 at 03:09:14PM +0530, cool dharma06 wrote:<br>
> I am newbie to this gdb debugging. now i did the bt in the debugging. In my<br>
> side still it showing the error. Following are the stacktrace which i got.<br>
> Kindly refer the following logs for full information:<br>
><br>
> ****<br>
> [New Thread 0x7f8503695700 (LWP 20012)]<br>
><br>
> Program received signal SIGSEGV, Segmentation fault.<br>
> 0x0000000000000000 in ?? ()<br>
> (gdb) bt<br>
> #0 0x0000000000000000 in ?? ()<br>
> #1 0x00007f84f671281e in libxl_osevent_occurred_timeout (ctx=<optimized<br>
> out>, for_libxl=0x7f8503bbbc38) at libxl_event.c:1039<br>
> #2 0x00007f84f69439c7 in libxlDomainObjTimerCallback (timer=<optimized<br>
> out>, timer_info=0x7f8503bb5930) at libxl/libxl_domain.c:216<br>
> #3 0x00007f8502ba6f7d in virEventPollDispatchTimeouts () at<br>
> util/vireventpoll.c:451<br>
> #4 virEventPollRunOnce () at util/vireventpoll.c:644<br>
> #5 0x00007f8502ba570b in virEventRunDefaultImpl () at util/virevent.c:274<br>
> #6 0x00007f8502cda065 in virNetServerRun (srv=0x7f8503ba6ba0) at<br>
> rpc/virnetserver.c:1112<br>
> #7 0x00007f85036c251c in main (argc=<optimized out>, argv=<optimized out>)<br>
> at libvirtd.c:1513<br>
> (gdb)<br>
<br>
</div>In this case, that stack trace looks like it ought to be sufficient<br>
to identify the problem - a clear NULL pointer reference. In general<br>
though you want to capture a stack trace of all threads in a program<br>
<br>
eg instead of 'bt', do 'thread apply all bt' next time.<br>
<br>
Regards,<br>
Daniel<br>
<span class="HOEnZb"><font color="#888888">--<br>
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</font></span></blockquote></div><br></div>