On 12/14/2011 08:39 AM, Avi Kivity wrote:

On 12/14/2011 02:16 PM, Marcelo Tosatti wrote:

quoted

quoted

Having this controlled from userspace means it doesn't work for SIGSTOP
or for long scheduling delays.  What about doing this automatically
based on preempt notifiers?

Long scheduling delays should be considered hangups from the guest
perspective.

Why?  To the guest it looks like slow hardware, but it will interpret it
as a softlockup.

quoted

About SIGSTOP, that is a corner case. Unsure if its even properly supported
by QEMU.

It works from my experience.

We don't adjust vm_clock's offset on SIGSTOP/SIGCONT so while it may appear to 
work okay, QEMU isn't exhibiting the behavior it is supposed to.

Regards,

Anthony Liguori