KVM: Let host know whether the guest can handle async PF in non-userspace context.

If guest can detect that it runs in non-preemptable context it can
handle async PFs at any time, so let host know that it can send async
PF even if guest cpu is not in userspace.

Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This commit is contained in:
Gleb Natapov
2010-10-14 11:22:55 +02:00
committed by Avi Kivity
parent 6c047cd982
commit 6adba52742
5 changed files with 11 additions and 4 deletions

View File

@@ -449,6 +449,9 @@ void __cpuinit kvm_guest_cpu_init(void)
if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF) && kvmapf) {
u64 pa = __pa(&__get_cpu_var(apf_reason));
#ifdef CONFIG_PREEMPT
pa |= KVM_ASYNC_PF_SEND_ALWAYS;
#endif
wrmsrl(MSR_KVM_ASYNC_PF_EN, pa | KVM_ASYNC_PF_ENABLED);
__get_cpu_var(apf_reason).enabled = 1;
printk(KERN_INFO"KVM setup async PF for cpu %d\n",