Re: [Qemu-devel] rtc: lost some interrupts at 1024Hz.

[Fabrice Bellard]

It seems to be a host kernel problem.

Regards,

Fabrice.

Brad Campbell wrote:
> G'day all,
>
> Just wonder if anyone else is seeing this. I've not had a chance to 
> track it down or try to debug it yet.
>
> I'm running latest QEMU CVS with kqemu and the -no-tsc patch on a 
> vanilla 2.6.17.3 kernel with suspend2.
>
> The VM behaves perfectly until I do a suspend/resume of the host. When 
> the machine comes back, most of the time (not all the time however) it 
> ends up flooding my logs with this message.
>
> Jul  8 17:26:03 localhost kernel: [43299223.910000] rtc: lost some 
> interrupts at 1024Hz.
> Jul  8 17:26:03 localhost kernel: [43299223.930000] rtc: lost some 
> interrupts at 1024Hz.
> Jul  8 17:26:03 localhost kernel: [43299223.950000] rtc: lost some 
> interrupts at 1024Hz.
> Jul  8 17:26:03 localhost kernel: [43299223.970000] rtc: lost some 
> interrupts at 1024Hz.
>
> Of course if I shutdown/reboot the VM the problem goes away. I've seen 
> this before but it's been a while from memory.
> I'm running a vanilla 2.6.17.3 kernel in the guest booted with GRUB and 
> both host and guest are configured with HZ=100.
>
> I seem to recall mplayer does the same thing if I leave something 
> playing over a suspend/resume, but I've not had a chance to look at it 
> further. It's pretty reproducible here with qemu anyway.
>
> This is about the only remaining thing that is preventing me leaving 
> VM's up over suspend/resume now. Other than that, it's all good.
>
> I'll probably get to looking at it in the next couple of weeks if nobody 
> has any pointers.
> Brad