[Qemu-devel] Re: KVM freeze when using --serial

[Thomas Kittel]

Hi again,

I just tried to use unix domain sockets.

So I used the parameter --monitor unix:monitor:server:nowait on the first VM
and the parameter --serial unix:monitor on the second VM,

And again the second VM freezes when running my test application.

cya Tom

Thomas Kittel wrote:
> Hi there,
>
> I already posted this problem to #kvm on freenode.
>
> Please set me in CC: when replying to this mail, as I am not 
> subscribed to this mailing lists right now.
>
> The Scenario is as follows:
>
> I got 2 VM processes in userspace.
>
> The first is started with the parameter --monitor pty.
>    => This results in a file /dev/pts/x in the host,
>        (crw--w---- 1 kittel tty 136, 3 2010-04-07 15:51 /dev/pts/3 on 
> my system)
>
> Another VM is then started with the parameter --serial /dev/pts/3
>    => This results in /dev/ttyS0 inside the second VM.
>
> Both VMs are running debian lenny. The host (debian) uses qemu-kvm 
> 0.12.3.
> "startvms.sh start" is used to start the VMs.
>
> Running the executable build from test.c in the second VM results in a 
> freeze of this VM.
> (The test.c included uses /dev/ttyS1 as /dev/ttyS0 is the VMs serial 
> console in my setup.)
> The process uses 100% CPU and is stuck in kvm_mutex_lock().
>
> Trying to use the build in gdbserver didn´t work because it also locked.
>
> Is there a way to tunnel one VMs monitor console to another VM?
>
> Thanks Thomas