In a previous mail, Jeremy Fitzhardinge wrote: > The softlockup watchdog is currently a nuisance in a virtual machine, > since the whole system could have the CPU stolen from it for a long > period of time. While it would be unlikely for a guest domain to be > denied timer interrupts for over 10s, it could happen and any > softlockup message would be completely spurious. I wonder how the guest domain can be denied timer interrupts for such a long time ? The only reason I see is that the guest domain is not scheduled at all (host domain or another higher priority guest running). Now in SMP host and guest, what happens if a guest CPU is not scheduled for a while ? An example: in kernel/pid.c:alloc_pid(), if one of the guest CPUs is descheduled when holding the pidmap_lock, what happens to the other guest CPUs who want to alloc/free pids ? Are they blocked too ? -- Cyprien Laplace _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
