* Marcus (shadow...@gmail.com) wrote: > Dang, I was hoping some ground was being made on this.
Can you answer the same questions I asked Marcin? What's the latest version of QEMU you've seen this on, what CPU are you using, what guest OS and what's your QEMU command line? Dave > > On Wed, Apr 2, 2014 at 11:05 AM, Marcin Gibu??a <m.gib...@beyond.pl> wrote: > >>> Yes, that's where it gets weird. I've never seen this on fresh VM. > >>> It needs to be idle for couple of hours at least. And even then it > >>> doesn't always hang. > >> > >> > >> So your OS is just sitting at a text console, running nothing special? > >> When you reboot after the migration what's the last thing you see > >> in the guests logs? Is there anything from after the migration? > > > > > > Yes, it's completely idle. After reboot there is nothing in logs. I've > > dumped memory of one of hanged test VMs and found kernel message buffer. The > > last entries were: > > > > > > init: failsafe main process (659) killed by TERM signal > > init: plymouth-upstart-bridge main process (651) killed by TERM signal > > > > <migration goes here, guest hangs> > > > > Clocksource tsc unstable (delta = 470666274 ns) > > > > <inject-nmi to test> > > > > Uhhuh. NMI received for unknown reason 30 on CPU 0. > > Do you have a strange power saving mode enabled?I: > > > > Dazed and confused, but trying to continue > > Uhhuh. NMI received for unknown reason 20 on CPU 0. > > Do you have a strange power saving mode enabled?I: > > > > Dazed and confused, but trying to continue > > <0>Dazed and confused, but trying to continue > > > > > > > > I've tried to disassemble where VM kernel (3.8.something from Ubuntu) is > > spinning (using qemu-monitor, registers info and symbols from guest kernel) > > and it was loop inside __run_timers function from kernel/timer.c: > > > > while (time_after_eq(jiffies, base->timer_jiffies)) { > > ... > > } > > > > However my disassembly and qemu debugging skills are limited, would it help > > if I dump memory of broken VM and send it you somehow? > > > > -- > > mg > > > > > > > -- Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK