1 files changed, 38 insertions, 1 deletions

diff --git a/arch/powerpc/kvm/book3s_64_rmhandlers.S b/arch/powerpc/kvm/book3s_64_rmhandlers.S
index cd9f0b609e48..9ad1c2645d6f 100644
--- a/arch/powerpc/kvm/book3s_64_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_64_rmhandlers.S
@@ -49,7 +49,7 @@ kvmppc_trampoline_\intno:
         mfcr    r12
         stw     r12, PACA_KVM_SCRATCH1(r13)
         lbz     r12, PACA_KVM_IN_GUEST(r13)
-        cmpwi   r12, 0
+        cmpwi   r12, KVM_GUEST_MODE_NONE
         bne     ..kvmppc_handler_hasmagic_\intno
         /* No KVM guest? Then jump back to the Linux handler! */
         lwz     r12, PACA_KVM_SCRATCH1(r13)
@@ -60,6 +60,11 @@ kvmppc_trampoline_\intno:
 
         /* Now we know we're handling a KVM guest */
 ..kvmppc_handler_hasmagic_\intno:
+
+        /* Should we just skip the faulting instruction? */
+        cmpwi   r12, KVM_GUEST_MODE_SKIP
+        beq     kvmppc_handler_skip_ins
+
         /* Let's store which interrupt we're handling */
         li      r12, \intno
 
@@ -86,6 +91,38 @@ INTERRUPT_TRAMPOLINE	BOOK3S_INTERRUPT_ALTIVEC
 INTERRUPT_TRAMPOLINE    BOOK3S_INTERRUPT_VSX
 
 /*
+ * Bring us back to the faulting code, but skip the
+ * faulting instruction.
+ *
+ * This is a generic exit path from the interrupt
+ * trampolines above.
+ *
+ * Input Registers:
+ *
+ * R12               = free
+ * R13               = PACA
+ * PACA.KVM.SCRATCH0 = guest R12
+ * PACA.KVM.SCRATCH1 = guest CR
+ * SPRG_SCRATCH0     = guest R13
+ *
+ */
+kvmppc_handler_skip_ins:
+
+        /* Patch the IP to the next instruction */
+        mfsrr0  r12
+        addi    r12, r12, 4
+        mtsrr0  r12
+
+        /* Clean up all state */
+        lwz     r12, PACA_KVM_SCRATCH1(r13)
+        mtcr    r12
+        ld      r12, PACA_KVM_SCRATCH0(r13)
+        mfspr   r13, SPRN_SPRG_SCRATCH0
+
+        /* And get back into the code */
+        RFI
+
+/*
  * This trampoline brings us back to a real mode handler
  *
  * Input Registers: