Re: Panic on a -current from 13/12/2018

[Masanobu SAITOH <msaitoh%execsw.org@localhost>]

On 2018/12/17 1:09, Chavdar Ivanov wrote:
> I have no idea. As I said, it is running under VirtualBox on a Windows
> 10 host; I put the host in hibernation whilst the NetBSD guest is
> running.

I tested today's -current on VirtualBox 5.2.22 on Windows 7 64bit
(on Core i7-2600). I tried hybernate(shutdown ->hybernate(H)) a few times
but I couldn't reproduce the problem yet.

> > > >          while (deltat > 0) {
> > > >                  xtick = lapic_gettick();
> > > >                  if (lapic_broken_periodic && xtick == 0 && otick == 0) {
> > > >                          lapic_initclocks();
> > > >                          xtick = lapic_gettick();
> > > >                          if (xtick == 0)
> > > >                                  panic("lapic timer stopped ticking");   <=========== here!
> > > >                  }

If that panic is from this, lapic_broken_periodic must be true, but it's set only
when the VM is KVM:
>                 /*
>                  * Apply workaround for broken periodic timer under KVM
>                  */
>                 if (vm_guest == VM_GUEST_KVM) {
>                         lapic_broken_periodic = true;
>                         lapic_timecounter.tc_quality = -100;
>                         aprint_debug_dev(ci->ci_dev,
>                             "applying KVM timer workaround\n");
>                 }

 Could you try to reproduce the problem and see the panic message?
ci4ic4-panic-01.png has backtrace and it wiped out the panic message.

 Regards.

> Previously it survived this, using the Intel Desktop NIC
> emulation within VirtualBox, even my ssh connections (from the host to
> the guest) remained active. I switched the NIC emulation for the
> NetBSD guest to virtio-net, now it behaves as before, surviving a
> hibernation.
>
> There was a VirtualBox upgrade a few weeks ago, perhaps the problem is there.
> On Sun, 16 Dec 2018 at 15:55, SAITOH Masanobu <msaitoh%execsw.org@localhost> wrote:
> > Hi.
> >
> > On 2018/12/16 18:09, Chavdar Ivanov wrote:
> > > Repeated this morning. Happens when the host hibernates when the
> > > machine is running. The initial trace is slightly different, but the
> > > lines with wm_gmii are the same, so for now I will switch to a
> > > different NIC emulator.
> >
> > In your .png:
> > > vpanic()
> > > lapic_delay()
> > > wm_gmii_mdic_readreg()
> > > .
> > > .
> > > .
> >
> > There is no panic message itself, but I suspect it's:
> > > static void
> > > lapic_delay(unsigned int usec)
> > > {
> > >          int32_t xtick, otick;
> > >          int64_t deltat;         /* XXX may want to be 64bit */
> > >
> > >          otick = lapic_gettick();
> > >
> > >          if (usec <= 0)
> > >                  return;
> > >          if (usec <= 25)
> > >                  deltat = lapic_delaytab[usec];
> > >          else
> > >                  deltat = (lapic_frac_cycle_per_usec * usec) >> 32;
> > >
> > >          while (deltat > 0) {
> > >                  xtick = lapic_gettick();
> > >                  if (lapic_broken_periodic && xtick == 0 && otick == 0) {
> > >                          lapic_initclocks();
> > >                          xtick = lapic_gettick();
> > >                          if (xtick == 0)
> > >                                  panic("lapic timer stopped ticking");   <=========== here!
> > >                  }
> > >                  if (xtick > otick)
> > >                          deltat -= lapic_tval - (xtick - otick);
> > >                  else
> > >                          deltat -= otick - xtick;
> > >                  otick = xtick;
> > >
> > >                  x86_pause();
> > >          }
> > > }
> >
> > Why does it cause?
> >
> >
> > > And yes, it used to survive many hibernations of the hosts before. I
> > > only had to adjust the time after waking the host up.
> > > On Sat, 15 Dec 2018 at 10:59, Chavdar Ivanov <ci4ic4%gmail.com@localhost> wrote:
> > > > Hi,
> > > >
> > > > On 8.99.27 AMD64 running under VirtualBox I got this morning the panic
> > > > in http://ci4ic4.tx0.org/ci4ic4-panic-01.png
> > > >
> > > > I have the  coredump, if it is of interest. I thought it might be
> > > > useful, as it is apparently in the wm driver.
> > > >
> > > > Chavdar
> > > > --
> > > > ----
> >
> >
> > --
> > -----------------------------------------------
> >                  SAITOH Masanobu (msaitoh%execsw.org@localhost
> >                                   msaitoh%netbsd.org@localhost)


--
-----------------------------------------------
                SAITOH Masanobu (msaitoh%execsw.org@localhost
                                 msaitoh%netbsd.org@localhost)