diff options
Diffstat (limited to 'arch/mips/kvm/mips.c')
| -rw-r--r-- | arch/mips/kvm/mips.c | 50 |
1 files changed, 46 insertions, 4 deletions
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c index e59cb6246f76..a25e0b73ee70 100644 --- a/arch/mips/kvm/mips.c +++ b/arch/mips/kvm/mips.c @@ -414,6 +414,24 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, return -ENOIOCTLCMD; } +/* + * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while + * the vCPU is running. + * + * This must be noinstr as instrumentation may make use of RCU, and this is not + * safe during the EQS. + */ +static int noinstr kvm_mips_vcpu_enter_exit(struct kvm_vcpu *vcpu) +{ + int ret; + + guest_state_enter_irqoff(); + ret = kvm_mips_callbacks->vcpu_run(vcpu); + guest_state_exit_irqoff(); + + return ret; +} + int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) { int r = -EINTR; @@ -434,7 +452,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) lose_fpu(1); local_irq_disable(); - guest_enter_irqoff(); + guest_timing_enter_irqoff(); trace_kvm_enter(vcpu); /* @@ -445,10 +463,23 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) */ smp_store_mb(vcpu->mode, IN_GUEST_MODE); - r = kvm_mips_callbacks->vcpu_run(vcpu); + r = kvm_mips_vcpu_enter_exit(vcpu); + + /* + * We must ensure that any pending interrupts are taken before + * we exit guest timing so that timer ticks are accounted as + * guest time. Transiently unmask interrupts so that any + * pending interrupts are taken. + * + * TODO: is there a barrier which ensures that pending interrupts are + * recognised? Currently this just hopes that the CPU takes any pending + * interrupts between the enable and disable. + */ + local_irq_enable(); + local_irq_disable(); trace_kvm_out(vcpu); - guest_exit_irqoff(); + guest_timing_exit_irqoff(); local_irq_enable(); out: @@ -1168,7 +1199,7 @@ static void kvm_mips_set_c0_status(void) /* * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV) */ -int kvm_mips_handle_exit(struct kvm_vcpu *vcpu) +static int __kvm_mips_handle_exit(struct kvm_vcpu *vcpu) { struct kvm_run *run = vcpu->run; u32 cause = vcpu->arch.host_cp0_cause; @@ -1357,6 +1388,17 @@ int kvm_mips_handle_exit(struct kvm_vcpu *vcpu) return ret; } +int noinstr kvm_mips_handle_exit(struct kvm_vcpu *vcpu) +{ + int ret; + + guest_state_exit_irqoff(); + ret = __kvm_mips_handle_exit(vcpu); + guest_state_enter_irqoff(); + + return ret; +} + /* Enable FPU for guest and restore context */ void kvm_own_fpu(struct kvm_vcpu *vcpu) { |