An exception might occur during decode (e.g., #PF during fetch). Currently, the exception is ignored and emulation is performed. Instead, emulation should be skipped and the fault should be injected. Skipping instruction should report a failure in this case.
Signed-off-by: Nadav Amit <[email protected]> --- arch/x86/kvm/emulate.c | 3 +++ arch/x86/kvm/x86.c | 8 ++++++++ 2 files changed, 11 insertions(+), 0 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 05a562b..e06dc98 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -3869,6 +3869,9 @@ done: if (ctxt->memopp && ctxt->memopp->type == OP_MEM && ctxt->rip_relative) ctxt->memopp->addr.mem.ea += ctxt->_eip; + if (rc == X86EMUL_PROPAGATE_FAULT) + ctxt->have_exception = true; + return (rc != X86EMUL_CONTINUE) ? EMULATION_FAILED : EMULATION_OK; } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 1171def..05fd3d7 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4443,10 +4443,17 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, } if (emulation_type & EMULTYPE_SKIP) { + if (ctxt->have_exception) + return EMULATE_FAIL; kvm_rip_write(vcpu, ctxt->_eip); return EMULATE_DONE; } + if (ctxt->have_exception) { + writeback = false; + goto post; + } + if (retry_instruction(ctxt, cr2, emulation_type)) return EMULATE_DONE; @@ -4470,6 +4477,7 @@ restart: return handle_emulation_failure(vcpu); } +post: if (ctxt->have_exception) { inject_emulated_exception(vcpu); r = EMULATE_DONE; -- 1.7.4.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
