diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 271fefb..9d08d8c 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -38,8 +38,7 @@
 
 #define KVM_MAX_VCPUS		NR_CPUS
 #define KVM_MAX_VCORES		NR_CPUS
-#define KVM_USER_MEM_SLOTS 32
-#define KVM_MEM_SLOTS_NUM KVM_USER_MEM_SLOTS
+#define KVM_USER_MEM_SLOTS	512
 
 #ifdef CONFIG_KVM_MMIO
 #define KVM_COALESCED_MMIO_PAGE_OFFSET 1
diff --git a/arch/powerpc/kvm/book3s_64_mmu.c b/arch/powerpc/kvm/book3s_64_mmu.c
index 774a253..9bf7031 100644
--- a/arch/powerpc/kvm/book3s_64_mmu.c
+++ b/arch/powerpc/kvm/book3s_64_mmu.c
@@ -377,15 +377,12 @@
 
 static void kvmppc_mmu_book3s_64_slbmte(struct kvm_vcpu *vcpu, u64 rs, u64 rb)
 {
-	struct kvmppc_vcpu_book3s *vcpu_book3s;
 	u64 esid, esid_1t;
 	int slb_nr;
 	struct kvmppc_slb *slbe;
 
 	dprintk("KVM MMU: slbmte(0x%llx, 0x%llx)\n", rs, rb);
 
-	vcpu_book3s = to_book3s(vcpu);
-
 	esid = GET_ESID(rb);
 	esid_1t = GET_ESID_1T(rb);
 	slb_nr = rb & 0xfff;
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 6b35269..2675ae3 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -833,6 +833,24 @@
 
 	vcpu->stat.sum_exits++;
 
+	/*
+	 * This can happen if an interrupt occurs in the last stages
+	 * of guest entry or the first stages of guest exit (i.e. after
+	 * setting paca->kvm_hstate.in_guest to KVM_GUEST_MODE_GUEST_HV
+	 * and before setting it to KVM_GUEST_MODE_HOST_HV).
+	 * That can happen due to a bug, or due to a machine check
+	 * occurring at just the wrong time.
+	 */
+	if (vcpu->arch.shregs.msr & MSR_HV) {
+		printk(KERN_EMERG "KVM trap in HV mode!\n");
+		printk(KERN_EMERG "trap=0x%x | pc=0x%lx | msr=0x%llx\n",
+			vcpu->arch.trap, kvmppc_get_pc(vcpu),
+			vcpu->arch.shregs.msr);
+		kvmppc_dump_regs(vcpu);
+		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		run->hw.hardware_exit_reason = vcpu->arch.trap;
+		return RESUME_HOST;
+	}
 	run->exit_reason = KVM_EXIT_UNKNOWN;
 	run->ready_for_interrupt_injection = 1;
 	switch (vcpu->arch.trap) {
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 3c6badc..6ee26de 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -2153,7 +2153,7 @@
 
 	/* Emulate H_SET_DABR/X on P8 for the sake of compat mode guests */
 2:	rlwimi	r5, r4, 5, DAWRX_DR | DAWRX_DW
-	rlwimi	r5, r4, 1, DAWRX_WT
+	rlwimi	r5, r4, 2, DAWRX_WT
 	clrrdi	r4, r4, 3
 	std	r4, VCPU_DAWR(r3)
 	std	r5, VCPU_DAWRX(r3)
@@ -2404,6 +2404,8 @@
 	 * guest as machine check causing guest to crash.
 	 */
 	ld	r11, VCPU_MSR(r9)
+	rldicl.	r0, r11, 64-MSR_HV_LG, 63 /* check if it happened in HV mode */
+	bne	mc_cont			/* if so, exit to host */
 	andi.	r10, r11, MSR_RI	/* check for unrecoverable exception */
 	beq	1f			/* Deliver a machine check to guest */
 	ld	r10, VCPU_PC(r9)
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 6fd2405..a3b182d 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -919,21 +919,17 @@
 				r = -ENXIO;
 				break;
 			}
-			vcpu->arch.vr.vr[reg->id - KVM_REG_PPC_VR0] = val.vval;
+			val.vval = vcpu->arch.vr.vr[reg->id - KVM_REG_PPC_VR0];
 			break;
 		case KVM_REG_PPC_VSCR:
 			if (!cpu_has_feature(CPU_FTR_ALTIVEC)) {
 				r = -ENXIO;
 				break;
 			}
-			vcpu->arch.vr.vscr.u[3] = set_reg_val(reg->id, val);
+			val = get_reg_val(reg->id, vcpu->arch.vr.vscr.u[3]);
 			break;
 		case KVM_REG_PPC_VRSAVE:
-			if (!cpu_has_feature(CPU_FTR_ALTIVEC)) {
-				r = -ENXIO;
-				break;
-			}
-			vcpu->arch.vrsave = set_reg_val(reg->id, val);
+			val = get_reg_val(reg->id, vcpu->arch.vrsave);
 			break;
 #endif /* CONFIG_ALTIVEC */
 		default:
@@ -974,17 +970,21 @@
 				r = -ENXIO;
 				break;
 			}
-			val.vval = vcpu->arch.vr.vr[reg->id - KVM_REG_PPC_VR0];
+			vcpu->arch.vr.vr[reg->id - KVM_REG_PPC_VR0] = val.vval;
 			break;
 		case KVM_REG_PPC_VSCR:
 			if (!cpu_has_feature(CPU_FTR_ALTIVEC)) {
 				r = -ENXIO;
 				break;
 			}
-			val = get_reg_val(reg->id, vcpu->arch.vr.vscr.u[3]);
+			vcpu->arch.vr.vscr.u[3] = set_reg_val(reg->id, val);
 			break;
 		case KVM_REG_PPC_VRSAVE:
-			val = get_reg_val(reg->id, vcpu->arch.vrsave);
+			if (!cpu_has_feature(CPU_FTR_ALTIVEC)) {
+				r = -ENXIO;
+				break;
+			}
+			vcpu->arch.vrsave = set_reg_val(reg->id, val);
 			break;
 #endif /* CONFIG_ALTIVEC */
 		default: