Re: [Qemu-discuss] qemu hangs

[Nerijus Baliūnas]

2016-08-16 20:26, Peter Maydell rašė:
> > Yes, it still hangs:
> >
> > # gdb /usr/bin/qemu-system-alpha
> > (gdb) r -S -no-user-config -nodefaults -nographic -M none -qmp
> > unix:/var/lib/libvirt/qemu/capabilities.monitor.sock,server,nowait -pidfile
> > /var/lib/libvirt/qemu/capabilities.pidfile
> > Starting program: /usr/bin/qemu-system-alpha -S -no-user-config -nodefaults
> > -nographic -M none -qmp
> > unix:/var/lib/libvirt/qemu/capabilities.monitor.sock,server,nowait -pidfile
> > /var/lib/libvirt/qemu/capabilities.pidfile
> > [Thread debugging using libthread_db enabled]
> > Using host libthread_db library "/lib64/libthread_db.so.1".
> > [New Thread 0x7fffc9708700 (LWP 13010)]
> > ^C
>
> Has it actually hung, or is it just waiting for you to talk
> QMP protocol to it on the socket ?

Probably hung, because the same command launches on another PC,
process is running and the shell returns.

> I think what is happening here is that libvirt starts these
> QEMU processes to query them for what they support. What should
> happen is that QEMU is started, libvirt talks QMP protocol to
> them and then stops the QEMU processes when it's found out the
> answers to its questions. I think we need to somehow get a
> log of what libvirt is doing on the QMP socket to find out
> whether this bug is in QEMU (eg libvirt asks it to do something
> and it hangs) or in libvirt (eg libvirt doesn't tell
> QEMU to quit).

Yes, but as I wrote above, the command runs on another PC
even without libvirt. So most probably something wrong with qemu.

The PC with a problem is quite old AMD Athlon 64 X2 Dual-Core
Processor TK-55.