Message ID | 4E947628.6020105@cn.fujitsu.com |
---|---|
State | New |
Headers | show |
[ dropped unaffected seabios from CC ] On 2011-10-11 19:00, Lai Jiangshan wrote: > From: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> > > Currently, NMI interrupt is blindly sent to all the vCPUs when NMI > button event happens. This doesn't properly emulate real hardware on > which NMI button event triggers LINT1. Because of this, NMI is sent to > the processor even when LINT1 is maskied in LVT. For example, this > causes the problem that kdump initiated by NMI sometimes doesn't work > on KVM, because kdump assumes NMI is masked on CPUs other than CPU0. > > With this patch, KVM_NMI ioctl is handled as follows. > > - When in-kernel irqchip is enabled, KVM_NMI ioctl is handled as a > request of triggering LINT1 on the processor. LINT1 is emulated in > in-kernel irqchip. > > - When in-kernel irqchip is disabled, KVM_NMI ioctl is handled as a > request of injecting NMI to the processor. This assumes LINT1 is > already emulated in userland. > > (laijs) Changed from v1: > Add KVM_NMI API document > Add KVM_CAP_USER_NMI > > Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> > Tested-by: Lai Jiangshan <laijs@cn.fujitsu.com> > --- > Documentation/virtual/kvm/api.txt | 20 ++++++++++++++++++++ > arch/x86/kvm/irq.h | 1 + > arch/x86/kvm/lapic.c | 7 +++++++ > arch/x86/kvm/x86.c | 12 ++++++++++++ > include/linux/kvm.h | 3 +++ > 5 files changed, 43 insertions(+), 0 deletions(-) > > diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt > index b0e4b9c..5c24cc3 100644 > --- a/Documentation/virtual/kvm/api.txt > +++ b/Documentation/virtual/kvm/api.txt > @@ -1430,6 +1430,26 @@ is supported; 2 if the processor requires all virtual machines to have > an RMA, or 1 if the processor can use an RMA but doesn't require it, > because it supports the Virtual RMA (VRMA) facility. > > +4.64 KVM_NMI > + > +Capability: KVM_CAP_USER_NMI KVM_CAP_LAPIC_NMI needs to be listed here as well. > +Architectures: x86 > +Type: vcpu ioctl > +Parameters: none > +Returns: 0 on success, -1 on error > + > +This ioctl injects NMI to the vcpu. > + > +If with capability KVM_CAP_LAPIC_NMI, KVM_NMI ioctl is handled as follows: > + > + - When in-kernel irqchip is enabled, KVM_NMI ioctl is handled as a > + request of triggering LINT1 on the processor. LINT1 is emulated in > + in-kernel lapic irqchip. > + > + - When in-kernel irqchip is disabled, KVM_NMI ioctl is handled as a > + request of injecting NMI to the processor. This assumes LINT1 is > + already emulated in userland lapic. Not sure if we document previous behaviour in the file as well. If we do, the !KVM_CAP_LAPIC_NMI case requires some words. > + > 5. The kvm_run structure > > Application code obtains a pointer to the kvm_run structure by > diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h > index 53e2d08..0c96315 100644 > --- a/arch/x86/kvm/irq.h > +++ b/arch/x86/kvm/irq.h > @@ -95,6 +95,7 @@ void kvm_pic_reset(struct kvm_kpic_state *s); > void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu); > void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu); > void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu); > +void kvm_apic_lint1_deliver(struct kvm_vcpu *vcpu); > void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu); > void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu); > void __kvm_migrate_timers(struct kvm_vcpu *vcpu); > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c > index 57dcbd4..87fe36a 100644 > --- a/arch/x86/kvm/lapic.c > +++ b/arch/x86/kvm/lapic.c > @@ -1039,6 +1039,13 @@ void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu) > kvm_apic_local_deliver(apic, APIC_LVT0); > } > > +void kvm_apic_lint1_deliver(struct kvm_vcpu *vcpu) > +{ > + struct kvm_lapic *apic = vcpu->arch.apic; > + > + kvm_apic_local_deliver(apic, APIC_LVT1); > +} > + > static struct kvm_timer_ops lapic_timer_ops = { > .is_periodic = lapic_is_periodic, > }; > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 84a28ea..6862ef7 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -2729,12 +2729,24 @@ static int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, > return 0; > } > > +#ifdef KVM_CAP_LAPIC_NMI Unneeded #ifdef, that CAP is always available on x86. > +static int kvm_vcpu_ioctl_nmi(struct kvm_vcpu *vcpu) > +{ > + if (irqchip_in_kernel(vcpu->kvm)) > + kvm_apic_lint1_deliver(vcpu); > + else > + kvm_inject_nmi(vcpu); > + > + return 0; > +} > +#else > static int kvm_vcpu_ioctl_nmi(struct kvm_vcpu *vcpu) > { > kvm_inject_nmi(vcpu); > > return 0; > } > +#endif > > static int vcpu_ioctl_tpr_access_reporting(struct kvm_vcpu *vcpu, > struct kvm_tpr_access_ctl *tac) > diff --git a/include/linux/kvm.h b/include/linux/kvm.h > index aace6b8..5253a5c 100644 > --- a/include/linux/kvm.h > +++ b/include/linux/kvm.h > @@ -554,6 +554,9 @@ struct kvm_ppc_pvinfo { > #define KVM_CAP_PPC_SMT 64 > #define KVM_CAP_PPC_RMA 65 > #define KVM_CAP_S390_GMAP 71 > +#ifdef KVM_CAP_USER_NMI #ifdef __KVM_HAVE_USER_NMI > +#define KVM_CAP_LAPIC_NMI 72 > +#endif > > #ifdef KVM_CAP_IRQ_ROUTING > Jan
(2011/10/12 2:00), Lai Jiangshan wrote: > From: Kenji Kaneshige<kaneshige.kenji@jp.fujitsu.com> > > Currently, NMI interrupt is blindly sent to all the vCPUs when NMI > button event happens. This doesn't properly emulate real hardware on > which NMI button event triggers LINT1. Because of this, NMI is sent to > the processor even when LINT1 is maskied in LVT. For example, this > causes the problem that kdump initiated by NMI sometimes doesn't work > on KVM, because kdump assumes NMI is masked on CPUs other than CPU0. > > With this patch, KVM_NMI ioctl is handled as follows. > > - When in-kernel irqchip is enabled, KVM_NMI ioctl is handled as a > request of triggering LINT1 on the processor. LINT1 is emulated in > in-kernel irqchip. > > - When in-kernel irqchip is disabled, KVM_NMI ioctl is handled as a > request of injecting NMI to the processor. This assumes LINT1 is > already emulated in userland. > > (laijs) Changed from v1: > Add KVM_NMI API document > Add KVM_CAP_USER_NMI > > Signed-off-by: Kenji Kaneshige<kaneshige.kenji@jp.fujitsu.com> > Tested-by: Lai Jiangshan<laijs@cn.fujitsu.com> > --- > Documentation/virtual/kvm/api.txt | 20 ++++++++++++++++++++ > arch/x86/kvm/irq.h | 1 + > arch/x86/kvm/lapic.c | 7 +++++++ > arch/x86/kvm/x86.c | 12 ++++++++++++ > include/linux/kvm.h | 3 +++ > 5 files changed, 43 insertions(+), 0 deletions(-) > > diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt > index b0e4b9c..5c24cc3 100644 > --- a/Documentation/virtual/kvm/api.txt > +++ b/Documentation/virtual/kvm/api.txt > @@ -1430,6 +1430,26 @@ is supported; 2 if the processor requires all virtual machines to have > an RMA, or 1 if the processor can use an RMA but doesn't require it, > because it supports the Virtual RMA (VRMA) facility. > > +4.64 KVM_NMI > + > +Capability: KVM_CAP_USER_NMI > +Architectures: x86 > +Type: vcpu ioctl > +Parameters: none > +Returns: 0 on success, -1 on error > + > +This ioctl injects NMI to the vcpu. > + > +If with capability KVM_CAP_LAPIC_NMI, KVM_NMI ioctl is handled as follows: > + > + - When in-kernel irqchip is enabled, KVM_NMI ioctl is handled as a > + request of triggering LINT1 on the processor. LINT1 is emulated in > + in-kernel lapic irqchip. > + > + - When in-kernel irqchip is disabled, KVM_NMI ioctl is handled as a > + request of injecting NMI to the processor. This assumes LINT1 is > + already emulated in userland lapic. > + > 5. The kvm_run structure > > Application code obtains a pointer to the kvm_run structure by > diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h > index 53e2d08..0c96315 100644 > --- a/arch/x86/kvm/irq.h > +++ b/arch/x86/kvm/irq.h > @@ -95,6 +95,7 @@ void kvm_pic_reset(struct kvm_kpic_state *s); > void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu); > void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu); > void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu); > +void kvm_apic_lint1_deliver(struct kvm_vcpu *vcpu); > void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu); > void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu); > void __kvm_migrate_timers(struct kvm_vcpu *vcpu); > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c > index 57dcbd4..87fe36a 100644 > --- a/arch/x86/kvm/lapic.c > +++ b/arch/x86/kvm/lapic.c > @@ -1039,6 +1039,13 @@ void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu) > kvm_apic_local_deliver(apic, APIC_LVT0); > } > > +void kvm_apic_lint1_deliver(struct kvm_vcpu *vcpu) > +{ > + struct kvm_lapic *apic = vcpu->arch.apic; > + > + kvm_apic_local_deliver(apic, APIC_LVT1); > +} > + > static struct kvm_timer_ops lapic_timer_ops = { > .is_periodic = lapic_is_periodic, > }; > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 84a28ea..6862ef7 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -2729,12 +2729,24 @@ static int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, > return 0; > } > > +#ifdef KVM_CAP_LAPIC_NMI > +static int kvm_vcpu_ioctl_nmi(struct kvm_vcpu *vcpu) > +{ > + if (irqchip_in_kernel(vcpu->kvm)) > + kvm_apic_lint1_deliver(vcpu); > + else > + kvm_inject_nmi(vcpu); > + > + return 0; > +} > +#else > static int kvm_vcpu_ioctl_nmi(struct kvm_vcpu *vcpu) > { > kvm_inject_nmi(vcpu); > > return 0; > } > +#endif I don't think we need to keep old kvm_vcpu_ioctl_nmi() behavior because it's clearly a bug. Regards, Kenji Kaneshige
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index b0e4b9c..5c24cc3 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -1430,6 +1430,26 @@ is supported; 2 if the processor requires all virtual machines to have an RMA, or 1 if the processor can use an RMA but doesn't require it, because it supports the Virtual RMA (VRMA) facility. +4.64 KVM_NMI + +Capability: KVM_CAP_USER_NMI +Architectures: x86 +Type: vcpu ioctl +Parameters: none +Returns: 0 on success, -1 on error + +This ioctl injects NMI to the vcpu. + +If with capability KVM_CAP_LAPIC_NMI, KVM_NMI ioctl is handled as follows: + + - When in-kernel irqchip is enabled, KVM_NMI ioctl is handled as a + request of triggering LINT1 on the processor. LINT1 is emulated in + in-kernel lapic irqchip. + + - When in-kernel irqchip is disabled, KVM_NMI ioctl is handled as a + request of injecting NMI to the processor. This assumes LINT1 is + already emulated in userland lapic. + 5. The kvm_run structure Application code obtains a pointer to the kvm_run structure by diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h index 53e2d08..0c96315 100644 --- a/arch/x86/kvm/irq.h +++ b/arch/x86/kvm/irq.h @@ -95,6 +95,7 @@ void kvm_pic_reset(struct kvm_kpic_state *s); void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu); void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu); void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu); +void kvm_apic_lint1_deliver(struct kvm_vcpu *vcpu); void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu); void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu); void __kvm_migrate_timers(struct kvm_vcpu *vcpu); diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 57dcbd4..87fe36a 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1039,6 +1039,13 @@ void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu) kvm_apic_local_deliver(apic, APIC_LVT0); } +void kvm_apic_lint1_deliver(struct kvm_vcpu *vcpu) +{ + struct kvm_lapic *apic = vcpu->arch.apic; + + kvm_apic_local_deliver(apic, APIC_LVT1); +} + static struct kvm_timer_ops lapic_timer_ops = { .is_periodic = lapic_is_periodic, }; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 84a28ea..6862ef7 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2729,12 +2729,24 @@ static int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, return 0; } +#ifdef KVM_CAP_LAPIC_NMI +static int kvm_vcpu_ioctl_nmi(struct kvm_vcpu *vcpu) +{ + if (irqchip_in_kernel(vcpu->kvm)) + kvm_apic_lint1_deliver(vcpu); + else + kvm_inject_nmi(vcpu); + + return 0; +} +#else static int kvm_vcpu_ioctl_nmi(struct kvm_vcpu *vcpu) { kvm_inject_nmi(vcpu); return 0; } +#endif static int vcpu_ioctl_tpr_access_reporting(struct kvm_vcpu *vcpu, struct kvm_tpr_access_ctl *tac) diff --git a/include/linux/kvm.h b/include/linux/kvm.h index aace6b8..5253a5c 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -554,6 +554,9 @@ struct kvm_ppc_pvinfo { #define KVM_CAP_PPC_SMT 64 #define KVM_CAP_PPC_RMA 65 #define KVM_CAP_S390_GMAP 71 +#ifdef KVM_CAP_USER_NMI +#define KVM_CAP_LAPIC_NMI 72 +#endif #ifdef KVM_CAP_IRQ_ROUTING