>>> On 11.09.15 at 03:18, <ko...@jp.fujitsu.com> wrote: > Jan Beulich <jbeul...@suse.com> writes: >> From: Kouya Shimura <ko...@jp.fujitsu.com> >> >> The ACPI PM timer is sometimes broken on live migration. >> Since vcpu->arch.hvm_vcpu.guest_time is always zero in other than >> "delay for missed ticks mode". Even in "delay for missed ticks mode", >> vcpu's guest_time field is not valid (i.e. zero) when >> the state of vcpu is "blocked". (see pt_save_timer function) >> >> The original author (Tim Deegan) of pmtimer_save() must have intended >> that it saves the last scheduled time of the vcpu. Unfortunately it was >> already implied this bug. FYI, there is no other timer mode than >> "delay for missed ticks mode" then. >> >> For consistency with HPET, pmtimer_save() should refer hvm_get_guest_time() >> to update the counter as well as hpet_save() does. >> >> Without this patch, the clock of windows server 2012R2 without HPET >> might leap forward several minutes on live migration. >> >> Signed-off-by: Kouya Shimura <ko...@jp.fujitsu.com> >> >> Retain use of ->arch.hvm_vcpu.guest_time when non-zero. Do the inverse >> adjustment for vHPET. > > I'm fine with this change. > Why not modify the subject too?
Right - adding "and hpet" to it. Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
