From 5c6cedf488a1144ac4f683f3ea1a642533d1dcd2 Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Thu, 29 Jul 2010 14:47:49 +0200 Subject: KVM: PPC: Add PV guest critical sections When running in hooked code we need a way to disable interrupts without clobbering any interrupts or exiting out to the hypervisor. To achieve this, we have an additional critical field in the shared page. If that field is equal to the r1 register of the guest, it tells the hypervisor that we're in such a critical section and thus may not receive any interrupts. Signed-off-by: Alexander Graf Signed-off-by: Avi Kivity --- arch/powerpc/kvm/book3s.c | 18 ++++++++++++++++-- arch/powerpc/kvm/booke.c | 15 +++++++++++++++ 2 files changed, 31 insertions(+), 2 deletions(-) (limited to 'arch/powerpc/kvm') diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c index 5cb5f0d9381..d6227ff0cea 100644 --- a/arch/powerpc/kvm/book3s.c +++ b/arch/powerpc/kvm/book3s.c @@ -251,14 +251,28 @@ int kvmppc_book3s_irqprio_deliver(struct kvm_vcpu *vcpu, unsigned int priority) int deliver = 1; int vec = 0; ulong flags = 0ULL; + ulong crit_raw = vcpu->arch.shared->critical; + ulong crit_r1 = kvmppc_get_gpr(vcpu, 1); + bool crit; + + /* Truncate crit indicators in 32 bit mode */ + if (!(vcpu->arch.shared->msr & MSR_SF)) { + crit_raw &= 0xffffffff; + crit_r1 &= 0xffffffff; + } + + /* Critical section when crit == r1 */ + crit = (crit_raw == crit_r1); + /* ... and we're in supervisor mode */ + crit = crit && !(vcpu->arch.shared->msr & MSR_PR); switch (priority) { case BOOK3S_IRQPRIO_DECREMENTER: - deliver = vcpu->arch.shared->msr & MSR_EE; + deliver = (vcpu->arch.shared->msr & MSR_EE) && !crit; vec = BOOK3S_INTERRUPT_DECREMENTER; break; case BOOK3S_IRQPRIO_EXTERNAL: - deliver = vcpu->arch.shared->msr & MSR_EE; + deliver = (vcpu->arch.shared->msr & MSR_EE) && !crit; vec = BOOK3S_INTERRUPT_EXTERNAL; break; case BOOK3S_IRQPRIO_SYSTEM_RESET: diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index 13e0747178e..104d0ee8c8a 100644 --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -147,6 +147,20 @@ static int kvmppc_booke_irqprio_deliver(struct kvm_vcpu *vcpu, int allowed = 0; ulong uninitialized_var(msr_mask); bool update_esr = false, update_dear = false; + ulong crit_raw = vcpu->arch.shared->critical; + ulong crit_r1 = kvmppc_get_gpr(vcpu, 1); + bool crit; + + /* Truncate crit indicators in 32 bit mode */ + if (!(vcpu->arch.shared->msr & MSR_SF)) { + crit_raw &= 0xffffffff; + crit_r1 &= 0xffffffff; + } + + /* Critical section when crit == r1 */ + crit = (crit_raw == crit_r1); + /* ... and we're in supervisor mode */ + crit = crit && !(vcpu->arch.shared->msr & MSR_PR); switch (priority) { case BOOKE_IRQPRIO_DTLB_MISS: @@ -181,6 +195,7 @@ static int kvmppc_booke_irqprio_deliver(struct kvm_vcpu *vcpu, case BOOKE_IRQPRIO_DECREMENTER: case BOOKE_IRQPRIO_FIT: allowed = vcpu->arch.shared->msr & MSR_EE; + allowed = allowed && !crit; msr_mask = MSR_CE|MSR_ME|MSR_DE; break; case BOOKE_IRQPRIO_DEBUG: -- cgit v1.2.3