Re: KVM VM(windows xp) reseted when running geekbench for about 2days

From: Gleb Natapov
Date: Fri Apr 19 2013 - 07:42:54 EST


On Fri, Apr 19, 2013 at 01:05:08AM +0000, Zhanghaoyu (A) wrote:
> >> On Thu, Apr 18, 2013 at 12:00:49PM +0000, Zhanghaoyu (A) wrote:
> >>> I start 10 VMs(windows xp), then running geekbench tool on them,
> >>> about 2 days, one of them was reset, I found the reset operation is
> >>> done by int kvm_cpu_exec(CPUArchState *env) {
> >>> ...
> >>> switch (run->exit_reason)
> >>> ...
> >>> case KVM_EXIT_SHUTDOWN:
> >>> DPRINTF("shutdown\n");
> >>> qemu_system_reset_request();
> >>> ret = EXCP_INTERRUPT;
> >>> break;
> >>> ...
> >>> }
> >>>
> >>> KVM_EXIT_SHUTDOWN exit reason was set previously in triple fault handle handle_triple_fault().
> >>>
> >> How do you know that reset was done here? This is not the only place
> >> where qemu_system_reset_request() is called.
> I used gdb to debug QEMU process, and add a breakpoint in qemu_system_reset_request(), when the case occurred, backtrace shown as below,
> (gdb) bt
> #0 qemu_system_reset_request () at vl.c:1964
> #1 0x00007f9ef9dc5991 in kvm_cpu_exec (env=0x7f9efac47100)
> at /gt/qemu-kvm-1.4/qemu-kvm-1.4/kvm-all.c:1602
> #2 0x00007f9ef9d5b229 in qemu_kvm_cpu_thread_fn (arg=0x7f9efac47100)
> at /gt/qemu-kvm-1.4/qemu-kvm-1.4/cpus.c:759
> #3 0x00007f9ef898b5f0 in start_thread () from /lib64/libpthread.so.0
> #4 0x00007f9ef86fa84d in clone () from /lib64/libc.so.6
> #5 0x0000000000000000 in ?? ()
>
> And, I add printk log in all place where KVM_EXIT_SHUTDOWN exit reason is set, only handle_triple_fault() was called.
> >
> >Make sure XP is not set to auto-reset in case of BSOD.
> No, winxp is not set to auto-reset in case of BSOD. No Winxp event log reported.
> >
> >Best regards,
> >Yan.
> >
> >>
> >>> What causes the triple fault?
> >>>
> >> Are you asking what is triple fault or why it happened in your case?
> What I asked is why triple fault happened in my case.
> >> For the former see here: http://en.wikipedia.org/wiki/Triple_fault
> >> For the later it is to late to tell after VM reset. You can run QEMU
> >> with -no-reboot -no-shutdown. VM will pause instead of rebooting and
> >> then you can examine what is going on.
> Great thanks, I'll run QEMU with -no-reboot -no-shutdown options, if VM paused in my case, what should I examined?
>
Register state "info registers" in the monitor for each vcpu. Code
around the instruction that faulted.

--
Gleb.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/