KVM virsh console lockups with FreeBSD 10

[Christian Kratzer]

Hi,

I have several FreeBSD 10-RELEASE amd64 VMs running on KVM under CentOS 6.5.

I use the KVM serial console with "virsh console" for out of band access to those VMs and can reproduce lockups of the console when pasting stuff into them.

I have following in the VM:

     ck at TEST:~ % uname -a
     FreeBSD webmail2.cksoft.de 10.0-RELEASE-p7 FreeBSD 10.0-RELEASE-p7 #0: Tue Jul  8 06:37:44 UTC 2014     root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC  amd64
     ck at TEST:~ % freebsd-version
     10.0-RELEASE-p8
     ck at TEST:~ % cat /boot/loader.conf
     comconsole_speed="115200"       # Set the current serial console speed
     console="comconsole"            # A comma separated list of console(s)
     ck at TEST:~ % grep ttyu0 /etc/ttys
     ttyu0   "/usr/libexec/getty std.115200" dialup  on  secure
     ck at TEST:~ %

and following in the KVM configuration file:

     <serial type='pty'>
       <target port='0'/>
     </serial>
     <console type='pty'>
       <target type='serial' port='0'/>
     </console>

I can happily type in the console and dump large file to the console without any problems.

But as soon I paste some text into the console it locks up and requires a reboot of the VM to come back to life.

I cannot see anything strange in ps when I check the hung connection:

     ck at TEST:~ % ps xawel | grep u0
        0 924    1   0  20  0 47660 2732 wait     Is   u0   0:00.02  login [pam] (login)
        0 942  924   0  20  0 23496 3512 pause    I    u0   0:00.03  -csh (csh)
        0 945  942   0  20  0 23372 3432 ttyin    I+   u0   0:00.01  vi
     ck at TEST:~ %

In above example the console hung after a couple of characters pasted into vi.

Any ideas on how to debug this ?

Greetings
Christian

-- 
Christian Kratzer                   CK Software GmbH
Email:   ck at cksoft.de               Wildberger Weg 24/2
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