From 6adba527420651b6cacaf392541c09fb108711a2 Mon Sep 17 00:00:00 2001 From: Gleb Natapov Date: Thu, 14 Oct 2010 11:22:55 +0200 Subject: 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 Signed-off-by: Gleb Natapov Signed-off-by: Marcelo Tosatti --- arch/x86/kernel/kvm.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch/x86/kernel/kvm.c') diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 47ea93e6b0d8..91b3d650898c 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -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", -- cgit v1.2.3