On Sun, Aug 01, 2010 at 11:54:38AM +0300, Avi Kivity wrote: > On 08/01/2010 11:28 AM, Gleb Natapov wrote: > >On Sat, Jul 31, 2010 at 08:25:13PM +0300, Avi Kivity wrote: > >> On 07/29/2010 03:11 PM, Gleb Natapov wrote: > >>>No need to update vcpu state since instruction is in the middle of the > >>>emulation. > >>> > >>>Signed-off-by: Gleb Natapov<gleb@xxxxxxxxxx> > >>>--- > >>> arch/x86/kvm/x86.c | 31 +++++++++++++------------------ > >>> 1 files changed, 13 insertions(+), 18 deletions(-) > >>> > >>>diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > >>>index 76fbc32..7e5f075 100644 > >>>--- a/arch/x86/kvm/x86.c > >>>+++ b/arch/x86/kvm/x86.c > >>>@@ -4057,32 +4057,27 @@ restart: > >>> return handle_emulation_failure(vcpu); > >>> } > >>> > >>>- toggle_interruptibility(vcpu, vcpu->arch.emulate_ctxt.interruptibility); > >>>- kvm_x86_ops->set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags); > >>>- memcpy(vcpu->arch.regs, c->regs, sizeof c->regs); > >>>- kvm_rip_write(vcpu, vcpu->arch.emulate_ctxt.eip); > >>>+ r = EMULATE_DONE; > >>> > >>>- if (vcpu->arch.emulate_ctxt.exception>= 0) { > >>>+ if (vcpu->arch.emulate_ctxt.exception>= 0) > >>> inject_emulated_exception(vcpu); > >>>- return EMULATE_DONE; > >>>- } > >>>- > >>>- if (vcpu->arch.pio.count) { > >>>+ else if (vcpu->arch.pio.count) { > >>> if (!vcpu->arch.pio.in) > >>> vcpu->arch.pio.count = 0; > >>>- return EMULATE_DO_MMIO; > >>>- } > >>>- > >>>- if (vcpu->mmio_needed) { > >>>+ r = EMULATE_DO_MMIO; > >>>+ } else if (vcpu->mmio_needed) { > >>> if (vcpu->mmio_is_write) > >>> vcpu->mmio_needed = 0; > >>>- return EMULATE_DO_MMIO; > >>>- } > >>>- > >>>- if (vcpu->arch.emulate_ctxt.restart) > >>>+ r = EMULATE_DO_MMIO; > >>>+ } else if (vcpu->arch.emulate_ctxt.restart) > >>> goto restart; > >>> > >>>- return EMULATE_DONE; > >>>+ toggle_interruptibility(vcpu, vcpu->arch.emulate_ctxt.interruptibility); > >>>+ kvm_x86_ops->set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags); > >>>+ memcpy(vcpu->arch.regs, c->regs, sizeof c->regs); > >>>+ kvm_rip_write(vcpu, vcpu->arch.emulate_ctxt.eip); > >>>+ > >>>+ return r; > >>> } > >>> EXPORT_SYMBOL_GPL(emulate_instruction); > >>> > >>What about kvm-tpr-opt.c? It uses rip after pio. > >> > >It uses rip _during_ pio. And pio emulation changes rip > >only at the end of emulation. > > But non-emulated pio does a skip_emulated_instruction() immediately > (or so the code in kvm-tpr-opt.c assumes: > Indeed, this is bug in non-emulated pio. But the patch does not change rip behaviour for emulated pio. vcpu->arch.emulate_ctxt.eip is updated only at the end of emulation. > >static void vtpr_ioport_write(void *opaque, uint32_t addr, uint32_t val) > >{ > > CPUState *env = cpu_single_env; > > uint32_t rip; > > > > cpu_synchronize_state(env); > > > > rip = env->eip - 2; > > write_byte_virt(env, rip, 0x66); > > write_byte_virt(env, rip + 1, 0x90); > > ) > > -- > error compiling committee.c: too many arguments to function -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html