tree 2ff1cf6f59b0591ea39c0457705188d5f46cb118
parent 62786b9e81a2dbe9c073a2ade52d33a2627d6d85
author Marcelo Tosatti <mtosatti@redhat.com> 1212781055 -0300
committer Avi Kivity <avi@qumranet.com> 1214299012 +0300

KVM: Fix race between timer migration and vcpu migration

A guest vcpu instance can be scheduled to a different physical CPU
between the test for KVM_REQ_MIGRATE_TIMER and local_irq_disable().

If that happens, the timer will only be migrated to the current pCPU on
the next exit, meaning that guest LAPIC timer event can be delayed until
a host interrupt is triggered.

Fix it by cancelling guest entry if any vcpu request is pending.  This
has the side effect of nicely consolidating vcpu->requests checks.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>