Commit 53fafdbb8b21f ("KVM: x86: switch KVMCLOCK base to monotonic raw clock") changed kvmclock to use tkr_raw instead of tkr_mono. However, the default kvmclock_offset for the VM was still based on the monotonic clock and, if the raw clock drifted enough from the monotonic clock, this could cause a negative system_time to be written to the guest's struct pvclock. RHEL5 does not like it and (if it boots fast enough to observe a negative time value) it hangs. This series fixes the issue by using the raw clock everywhere. (And this, ladies and gentlemen, is why I was not applying patches to the KVM tree. I saw this before Christmas and could only reproduce it today, since it requires almost 2 weeks of uptime to reproduce on my machine. Of course, once you have the reproducer the fix is relatively easy to come up with). Paolo Paolo Bonzini (2): KVM: x86: reorganize pvclock_gtod_data members KVM: x86: use raw clock values consistently arch/x86/kvm/x86.c | 67 ++++++++++++++++++++++++++++-------------------------- 1 file changed, 35 insertions(+), 32 deletions(-) -- 1.8.3.1