From: Gleb Natapov <[email protected]> Do not recheck io permission on every iteration.
Signed-off-by: Gleb Natapov <[email protected]> Signed-off-by: Avi Kivity <[email protected]> diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h index f397b79..3c7dd29 100644 --- a/arch/x86/include/asm/kvm_emulate.h +++ b/arch/x86/include/asm/kvm_emulate.h @@ -219,6 +219,7 @@ struct x86_emulate_ctxt { int interruptibility; bool restart; /* restart string instruction after writeback */ + bool perm_ok; /* do not check permissions if true */ int exception; /* exception that happens during emulation or -1 */ u32 error_code; /* error code for exception */ diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 05f80f7..acbf283 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -1622,9 +1622,15 @@ static bool emulator_io_permited(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops, u16 port, u16 len) { + if (ctxt->perm_ok) + return true; + if (emulator_bad_iopl(ctxt, ops)) if (!emulator_io_port_access_allowed(ctxt, ops, port, len)) return false; + + ctxt->perm_ok = true; + return true; } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c5878d8..e7e3b50 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3997,6 +3997,7 @@ int emulate_instruction(struct kvm_vcpu *vcpu, memcpy(c->regs, vcpu->arch.regs, sizeof c->regs); vcpu->arch.emulate_ctxt.interruptibility = 0; vcpu->arch.emulate_ctxt.exception = -1; + vcpu->arch.emulate_ctxt.perm_ok = false; r = x86_decode_insn(&vcpu->arch.emulate_ctxt); trace_kvm_emulate_insn_start(vcpu); -- To unsubscribe from this list: send the line "unsubscribe kvm-commits" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
