From: Fan Zhang Date: Wed, 13 May 2015 08:58:41 +0000 (+0200) Subject: KVM: s390: host STP toleration for VMs X-Git-Tag: omap-for-v4.3/fixes-merge-window~47^2~1^2~1 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fdf036507f1fc036d5a06753e9e8b13f46de73e8;p=pandora-kernel.git KVM: s390: host STP toleration for VMs If the host has STP enabled, the TOD of the host will be changed during synchronization phases. These are performed during a stop_machine() call. As the guest TOD is based on the host TOD, we have to make sure that: - no VCPU is in the SIE (implicitly guaranteed via stop_machine()) - manual guest TOD calculations are not affected "Epoch" is the guest TOD clock delta to the host TOD clock. We have to adjust that value during the STP synchronization and make sure that code that accesses the epoch won't get interrupted in between (via disabling preemption). Signed-off-by: Fan Zhang Reviewed-by: David Hildenbrand Reviewed-by: Christian Borntraeger Acked-by: Martin Schwidefsky Signed-off-by: Christian Borntraeger --- Reading git-diff-tree failed