KVM: PPC: Book3S HV: Fix instruction emulation

paulusmack · agraf · commit 2bf27601c7b5 · 2015-03-20T11:42:33.000+01:00
Commit 4a157d6 ("KVM: PPC: Book3S HV: Fix endianness of instruction obtained from HEIR register") had the side effect that we no longer reset vcpu->arch.last_inst to -1 on guest exit in the cases where the instruction is not fetched from the guest. This means that if instruction emulation turns out to be required in those cases, the host will emulate the wrong instruction, since vcpu->arch.last_inst will contain the last instruction that was emulated. This fixes it by making sure that vcpu->arch.last_inst is reset to -1 in those cases. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -1005,6 +1005,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	/* Save HEIR (HV emulation assist reg) in emul_inst
 	   if this is an HEI (HV emulation interrupt, e40) */
 	li	r3,KVM_INST_FETCH_FAILED
+	stw	r3,VCPU_LAST_INST(r9)
 	cmpwi	r12,BOOK3S_INTERRUPT_H_EMUL_ASSIST
 	bne	11f
 	mfspr	r3,SPRN_HEIR
