diff --git a/arch/powerpc/include/asm/kvm_book3s_asm.h b/arch/powerpc/include/asm/kvm_book3s_asm.h index 0bd9348a4db91264d5e8a104f17ed77afcd5f815..412b2f389474a3c6c9b27120cf6f208fc5b25c8a 100644 --- a/arch/powerpc/include/asm/kvm_book3s_asm.h +++ b/arch/powerpc/include/asm/kvm_book3s_asm.h @@ -106,6 +106,7 @@ struct kvmppc_host_state { }; struct kvmppc_book3s_shadow_vcpu { + bool in_use; ulong gpr[14]; u32 cr; u32 xer; diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index fe14ca3dd171cd60b3c07191fa3bdd78a141e2a6..5b9e9063cfaf0c407be267a67ab26d35fcc84a93 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -66,6 +66,7 @@ static void kvmppc_core_vcpu_load_pr(struct kvm_vcpu *vcpu, int cpu) struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); memcpy(svcpu->slb, to_book3s(vcpu)->slb_shadow, sizeof(svcpu->slb)); svcpu->slb_max = to_book3s(vcpu)->slb_shadow_max; + svcpu->in_use = 0; svcpu_put(svcpu); #endif vcpu->cpu = smp_processor_id(); @@ -78,6 +79,9 @@ static void kvmppc_core_vcpu_put_pr(struct kvm_vcpu *vcpu) { #ifdef CONFIG_PPC_BOOK3S_64 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + if (svcpu->in_use) { + kvmppc_copy_from_svcpu(vcpu, svcpu); + } memcpy(to_book3s(vcpu)->slb_shadow, svcpu->slb, sizeof(svcpu->slb)); to_book3s(vcpu)->slb_shadow_max = svcpu->slb_max; svcpu_put(svcpu); @@ -110,12 +114,26 @@ void kvmppc_copy_to_svcpu(struct kvmppc_book3s_shadow_vcpu *svcpu, svcpu->ctr = vcpu->arch.ctr; svcpu->lr = vcpu->arch.lr; svcpu->pc = vcpu->arch.pc; + svcpu->in_use = true; } /* Copy data touched by real-mode code from shadow vcpu back to vcpu */ void kvmppc_copy_from_svcpu(struct kvm_vcpu *vcpu, struct kvmppc_book3s_shadow_vcpu *svcpu) { + /* + * vcpu_put would just call us again because in_use hasn't + * been updated yet. + */ + preempt_disable(); + + /* + * Maybe we were already preempted and synced the svcpu from + * our preempt notifiers. Don't bother touching this svcpu then. + */ + if (!svcpu->in_use) + goto out; + vcpu->arch.gpr[0] = svcpu->gpr[0]; vcpu->arch.gpr[1] = svcpu->gpr[1]; vcpu->arch.gpr[2] = svcpu->gpr[2]; @@ -139,6 +157,10 @@ void kvmppc_copy_from_svcpu(struct kvm_vcpu *vcpu, vcpu->arch.fault_dar = svcpu->fault_dar; vcpu->arch.fault_dsisr = svcpu->fault_dsisr; vcpu->arch.last_inst = svcpu->last_inst; + svcpu->in_use = false; + +out: + preempt_enable(); } static int kvmppc_core_check_requests_pr(struct kvm_vcpu *vcpu)