Jan Kiszka wrote: > User space may not want to overwrite asynchronously changing VCPU event > states on write-back. So allow to skip nmi.pending and sipi_vector by > setting corresponding bits in the flags field of kvm_vcpu_events. >
What will happen to this patch now? Merge during 2.6.33 window or drop? Jan > Signed-off-by: Jan Kiszka <[email protected]> > --- > > Documentation/kvm/api.txt | 10 +++++++++- > arch/x86/include/asm/kvm.h | 4 ++++ > arch/x86/kvm/x86.c | 9 ++++++--- > 3 files changed, 19 insertions(+), 4 deletions(-) > > diff --git a/Documentation/kvm/api.txt b/Documentation/kvm/api.txt > index e1a1141..ee07e3a 100644 > --- a/Documentation/kvm/api.txt > +++ b/Documentation/kvm/api.txt > @@ -685,7 +685,7 @@ struct kvm_vcpu_events { > __u8 pad; > } nmi; > __u32 sipi_vector; > - __u32 flags; /* must be zero */ > + __u32 flags; > }; > > 4.30 KVM_SET_VCPU_EVENTS > @@ -701,6 +701,14 @@ vcpu. > > See KVM_GET_VCPU_EVENTS for the data structure. > > +Fields that may be modified asynchronously by running VCPUs can be excluded > +from the update. These fields are nmi.pending and sipi_vector. Set the > +corresponding mask bits in the flags field to suppress overwriting their > +current state: > + > +KVM_VCPUEVENT_MASK_NMI_PENDING - do not update nmi.pending > +KVM_VCPUEVENT_MASK_SIPI_VECTOR - do not update sipi_vector > + > > 5. The kvm_run structure > > diff --git a/arch/x86/include/asm/kvm.h b/arch/x86/include/asm/kvm.h > index 950df43..acf8585 100644 > --- a/arch/x86/include/asm/kvm.h > +++ b/arch/x86/include/asm/kvm.h > @@ -254,6 +254,10 @@ struct kvm_reinject_control { > __u8 reserved[31]; > }; > > +/* When set in flags, skip corresponding fields on KVM_SET_VCPU_EVENTS */ > +#define KVM_VCPUEVENT_MASK_NMI_PENDING 0x00000001 > +#define KVM_VCPUEVENT_MASK_SIPI_VECTOR 0x00000002 > + > /* for KVM_GET/SET_VCPU_EVENTS */ > struct kvm_vcpu_events { > struct { > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index dd15d7a..368843c 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -1953,7 +1953,8 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct > kvm_vcpu *vcpu, > static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu, > struct kvm_vcpu_events *events) > { > - if (events->flags) > + if (events->flags & > + ~(KVM_VCPUEVENT_MASK_NMI_PENDING | KVM_VCPUEVENT_MASK_SIPI_VECTOR)) > return -EINVAL; > > vcpu_load(vcpu); > @@ -1970,10 +1971,12 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct > kvm_vcpu *vcpu, > kvm_pic_clear_isr_ack(vcpu->kvm); > > vcpu->arch.nmi_injected = events->nmi.injected; > - vcpu->arch.nmi_pending = events->nmi.pending; > + if (!(events->flags & KVM_VCPUEVENT_MASK_NMI_PENDING)) > + vcpu->arch.nmi_pending = events->nmi.pending; > kvm_x86_ops->set_nmi_mask(vcpu, events->nmi.masked); > > - vcpu->arch.sipi_vector = events->sipi_vector; > + if (!(events->flags & KVM_VCPUEVENT_MASK_SIPI_VECTOR)) > + vcpu->arch.sipi_vector = events->sipi_vector; > > vcpu_put(vcpu); > > -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
