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

[Brad Campbell]

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
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