On 22 Feb 2014, at 00:57, Matt Lupfer wrote: > I did some more debugging and found the problem was elsewhere. This > different timer behavior is exposing a bug in the HPET implementation. > > It's possible for the QEMU timer underlying the HPET to call the hpet_timer() > callback between when the timer is created and when the HPET device is > enabled (both actions initiated by the guest writing to HPET registers). > When this happens, the QEMU timer is rearmed to an expiration > time based on uninitialized values. That's preventing the system timer > interrupt from ticking in the guest during the timer check at boot. > > The changes to the timer implementation just makes this a lot more likely > to happen on CentOS 5.x kernels.
Thanks for debugging this. The timer changes for better or for worse seem to be quite good at uncovering bugs elsewhere. -- Alex Bligh
