From 61db97cc1e7fce4fd16f72b1350e1728797fa26f Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Fri, 16 Apr 2010 00:11:52 +0200 Subject: [PATCH] KVM: PPC: Emulate segment fault Book3S_32 doesn't know about segment faults. It only knows about page faults. So in order to know that we didn't map a segment, we need to fake segment faults. We do this by setting invalid segment registers to an invalid VSID and then check for that VSID on normal page faults. Signed-off-by: Alexander Graf Signed-off-by: Avi Kivity --- arch/powerpc/kvm/book3s.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c index d0986968a61..f8ac26599f6 100644 --- a/arch/powerpc/kvm/book3s.c +++ b/arch/powerpc/kvm/book3s.c @@ -775,6 +775,18 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu, switch (exit_nr) { case BOOK3S_INTERRUPT_INST_STORAGE: vcpu->stat.pf_instruc++; + +#ifdef CONFIG_PPC_BOOK3S_32 + /* We set segments as unused segments when invalidating them. So + * treat the respective fault as segment fault. */ + if (to_svcpu(vcpu)->sr[kvmppc_get_pc(vcpu) >> SID_SHIFT] + == SR_INVALID) { + kvmppc_mmu_map_segment(vcpu, kvmppc_get_pc(vcpu)); + r = RESUME_GUEST; + break; + } +#endif + /* only care about PTEG not found errors, but leave NX alone */ if (to_svcpu(vcpu)->shadow_srr1 & 0x40000000) { r = kvmppc_handle_pagefault(run, vcpu, kvmppc_get_pc(vcpu), exit_nr); @@ -799,6 +811,17 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu, { ulong dar = kvmppc_get_fault_dar(vcpu); vcpu->stat.pf_storage++; + +#ifdef CONFIG_PPC_BOOK3S_32 + /* We set segments as unused segments when invalidating them. So + * treat the respective fault as segment fault. */ + if ((to_svcpu(vcpu)->sr[dar >> SID_SHIFT]) == SR_INVALID) { + kvmppc_mmu_map_segment(vcpu, dar); + r = RESUME_GUEST; + break; + } +#endif + /* The only case we need to handle is missing shadow PTEs */ if (to_svcpu(vcpu)->fault_dsisr & DSISR_NOHPTE) { r = kvmppc_handle_pagefault(run, vcpu, dar, exit_nr); -- 2.46.0