Re: [libvirt] cont command failing via JSON monitor on restore
Jim Fehlig wrote:
Agreed. What error do you get back from the text monitor when cont
cmd
fails? I'd be interested in the following output from
$root/src/qemu/qemu_monitor_text.c:qemuMonitorCommandWithHandler()
VIR_DEBUG("Receive command reply ret=%d errno=%d %d bytes '%s'",
ret, msg.lastErrno, msg.rxLength, msg.rxBuffer);
Since I cannot reproduce the issue with qemu 0.13 using the text
monitor, I hacked qemu to simulate the error and got the following from
the debug message
Receive command reply ret=0 errno=0 71 bytes 'An incoming migration is
expected before this command can be executed'
msg.lastErrno is 0 (which is why ret is 0), but we've received the "An
incoming migration ..." error message. The message is available in
reply variable in
$root/src/qemu/qemu_monitor_text.c:qemuMonitorTextStartCPUs(), but
that's not a very robust way to check for error. Seems qemu should
return an error in addition to the message. I'm not familiar with the
qemu monitor code, but I suspect the qemu patch you referenced [1] was
insufficient wrt the text monitor.
I think a patch addressing the issue in the JSON monitor, where we can
reliably detect the error, is a good start. Would that be okay? Also,
recall that I cannot reproduce the issue with qemu 0.13. Perhaps other
post-0.12.5 changes have "fixed" the bug in the text monitor.
Regards,
Jim
[1] http://lists.gnu.org/archive/html/qemu-devel/2010-07/msg01574.html