diff options
| author | Gleb Natapov <gleb@redhat.com> | 2010-10-14 11:22:55 +0200 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2011-01-12 11:23:21 +0200 |
| commit | 6adba527420651b6cacaf392541c09fb108711a2 (patch) | |
| tree | 1f81e4fc0bdf46b39ed62587a493f085633e8ac1 | |
| parent | 6c047cd982f944fa63b2d96de2a06463d113f9fa (diff) | |
| download | op-kernel-dev-6adba527420651b6cacaf392541c09fb108711a2.zip op-kernel-dev-6adba527420651b6cacaf392541c09fb108711a2.tar.gz | |
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>
| -rw-r--r-- | Documentation/kvm/msr.txt | 5 | ||||
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 1 | ||||
| -rw-r--r-- | arch/x86/include/asm/kvm_para.h | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/kvm.c | 3 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 5 |
5 files changed, 11 insertions, 4 deletions
diff --git a/Documentation/kvm/msr.txt b/Documentation/kvm/msr.txt index e67b4a8..d079aed 100644 --- a/Documentation/kvm/msr.txt +++ b/Documentation/kvm/msr.txt @@ -154,9 +154,10 @@ MSR_KVM_SYSTEM_TIME: 0x12 MSR_KVM_ASYNC_PF_EN: 0x4b564d02 data: Bits 63-6 hold 64-byte aligned physical address of a 64 byte memory area which must be in guest RAM and must be - zeroed. Bits 5-1 are reserved and should be zero. Bit 0 is 1 + zeroed. Bits 5-2 are reserved and should be zero. Bit 0 is 1 when asynchronous page faults are enabled on the vcpu 0 when - disabled. + disabled. Bit 2 is 1 if asynchronous page faults can be injected + when vcpu is in cpl == 0. First 4 byte of 64 byte memory location will be written to by the hypervisor at the time of asynchronous page fault (APF) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 167375c..b2ea428 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -422,6 +422,7 @@ struct kvm_vcpu_arch { struct gfn_to_hva_cache data; u64 msr_val; u32 id; + bool send_user_only; } apf; }; diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h index fbfd367..d3a1a48 100644 --- a/arch/x86/include/asm/kvm_para.h +++ b/arch/x86/include/asm/kvm_para.h @@ -38,6 +38,7 @@ #define KVM_MAX_MMU_OP_BATCH 32 #define KVM_ASYNC_PF_ENABLED (1 << 0) +#define KVM_ASYNC_PF_SEND_ALWAYS (1 << 1) /* Operations for KVM_HC_MMU_OP */ #define KVM_MMU_OP_WRITE_PTE 1 diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 47ea93e..91b3d65 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", diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index ac4c368..fff70b5 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1429,8 +1429,8 @@ static int kvm_pv_enable_async_pf(struct kvm_vcpu *vcpu, u64 data) { gpa_t gpa = data & ~0x3f; - /* Bits 1:5 are resrved, Should be zero */ - if (data & 0x3e) + /* Bits 2:5 are resrved, Should be zero */ + if (data & 0x3c) return 1; vcpu->arch.apf.msr_val = data; @@ -1444,6 +1444,7 @@ static int kvm_pv_enable_async_pf(struct kvm_vcpu *vcpu, u64 data) if (kvm_gfn_to_hva_cache_init(vcpu->kvm, &vcpu->arch.apf.data, gpa)) return 1; + vcpu->arch.apf.send_user_only = !(data & KVM_ASYNC_PF_SEND_ALWAYS); kvm_async_pf_wakeup_all(vcpu); return 0; } |
