Commit 37f5bca6 authored Feb 19, 2010 by Alexander Graf Committed by Avi Kivity Apr 25, 2010

KVM: PPC: Add AGAIN type for emulation return



Emulation of an instruction can have different outcomes. It can succeed,
fail, require MMIO, do funky BookE stuff - or it can just realize something's
odd and will be fixed the next time around.

Exactly that is what EMULATE_AGAIN means. Using that flag we can now tell
the caller that nothing happened, but we still want to go back to the
guest and see what happens next time we come around.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>

parent 3587d534

arch/powerpc/include/asm/kvm_ppc.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -37,6 +37,7 @@ enum emulation_result {
		EMULATE_DO_MMIO, /* kvm_run filled with MMIO request */
		EMULATE_DO_DCR, /* kvm_run filled with DCR request */
		EMULATE_FAIL, /* can't emulate this instruction */
		EMULATE_AGAIN, /* something went wrong. go again */
		};

		extern int __kvmppc_vcpu_run(struct kvm_run kvm_run, struct kvm_vcpu vcpu);

arch/powerpc/kvm/book3s.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -789,6 +789,9 @@ int kvmppc_handle_exit(struct kvm_run run, struct kvm_vcpu vcpu,
		case EMULATE_DONE:
		r = RESUME_GUEST_NV;
		break;
		case EMULATE_AGAIN:
		r = RESUME_GUEST;
		break;
		case EMULATE_FAIL:
		printk(KERN_CRIT "%s: emulation at %lx failed (%08x)\n",
		__func__, vcpu->arch.pc, vcpu->arch.last_inst);

arch/powerpc/kvm/emulate.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -486,7 +486,9 @@ int kvmppc_emulate_instruction(struct kvm_run run, struct kvm_vcpu vcpu)

		if (emulated == EMULATE_FAIL) {
		emulated = kvmppc_core_emulate_op(run, vcpu, inst, &advance);
		if (emulated == EMULATE_FAIL) {
		if (emulated == EMULATE_AGAIN) {
		advance = 0;
		} else if (emulated == EMULATE_FAIL) {
		advance = 0;
		printk(KERN_ERR "Couldn't emulate instruction 0x%08x "
		"(op %d xop %d)\n", inst, get_op(inst), get_xop(inst));