diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h
index 090fcd1..c235867 100644
--- a/arch/powerpc/include/asm/exception-64s.h
+++ b/arch/powerpc/include/asm/exception-64s.h
@@ -147,8 +147,9 @@ END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,943)
 
 #define __EXCEPTION_PROLOG_1(area, extra, vec)				\
 	GET_PACA(r13);							\
-	std	r9,area+EX_R9(r13);	/* save r9 - r12 */		\
-	std	r10,area+EX_R10(r13);					\
+	std	r9,area+EX_R9(r13);	/* save r9 */			\
+	HMT_MEDIUM_PPR_SAVE(area, r9);					\
+	std	r10,area+EX_R10(r13);	/* save r10 - r12 */		\
 	BEGIN_FTR_SECTION_NESTED(66);					\
 	mfspr	r10,SPRN_CFAR;						\
 	std	r10,area+EX_CFAR(r13);					\
@@ -264,6 +265,7 @@ do_kvm_##n:								\
 	std	r10,GPR1(r1);		/* save r1 in stackframe	*/ \
 	beq	4f;			/* if from kernel mode		*/ \
 	ACCOUNT_CPU_USER_ENTRY(r9, r10);				   \
+	SAVE_PPR(area, r9, r10);					   \
 4:	std	r2,GPR2(r1);		/* save r2 in stackframe	*/ \
 	SAVE_4GPRS(3, r1);		/* save r3 - r6 in stackframe	*/ \
 	SAVE_2GPRS(7, r1);		/* save r7, r8 in stackframe	*/ \
@@ -305,7 +307,7 @@ do_kvm_##n:								\
 	. = loc;					\
 	.globl label##_pSeries;				\
 label##_pSeries:					\
-	HMT_MEDIUM;					\
+	HMT_MEDIUM_PPR_DISCARD;				\
 	SET_SCRATCH0(r13);		/* save r13 */		\
 	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common,	\
 				 EXC_STD, KVMTEST_PR, vec)
@@ -314,7 +316,7 @@ label##_pSeries:					\
 	. = loc;					\
 	.globl label##_hv;				\
 label##_hv:						\
-	HMT_MEDIUM;					\
+	HMT_MEDIUM_PPR_DISCARD;				\
 	SET_SCRATCH0(r13);	/* save r13 */			\
 	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common,	\
 				 EXC_HV, KVMTEST, vec)
@@ -323,7 +325,7 @@ label##_hv:						\
 	. = loc;					\
 	.globl label##_relon_pSeries;			\
 label##_relon_pSeries:					\
-	HMT_MEDIUM;					\
+	HMT_MEDIUM_PPR_DISCARD;				\
 	/* No guest interrupts come through here */	\
 	SET_SCRATCH0(r13);		/* save r13 */	\
 	EXCEPTION_RELON_PROLOG_PSERIES(PACA_EXGEN, label##_common, \
@@ -333,7 +335,7 @@ label##_relon_pSeries:					\
 	. = loc;					\
 	.globl label##_relon_hv;			\
 label##_relon_hv:					\
-	HMT_MEDIUM;					\
+	HMT_MEDIUM_PPR_DISCARD;				\
 	/* No guest interrupts come through here */	\
 	SET_SCRATCH0(r13);	/* save r13 */		\
 	EXCEPTION_RELON_PROLOG_PSERIES(PACA_EXGEN, label##_common, \
@@ -368,7 +370,7 @@ label##_relon_hv:					\
 #define SOFTEN_NOTEST_HV(vec)		_SOFTEN_TEST(EXC_HV, vec)
 
 #define __MASKABLE_EXCEPTION_PSERIES(vec, label, h, extra)		\
-	HMT_MEDIUM;							\
+	HMT_MEDIUM_PPR_DISCARD;						\
 	SET_SCRATCH0(r13);    /* save r13 */				\
 	__EXCEPTION_PROLOG_1(PACA_EXGEN, extra, vec);		\
 	EXCEPTION_PROLOG_PSERIES_1(label##_common, h);
@@ -390,7 +392,7 @@ label##_hv:								\
 				    EXC_HV, SOFTEN_TEST_HV)
 
 #define __MASKABLE_RELON_EXCEPTION_PSERIES(vec, label, h, extra)	\
-	HMT_MEDIUM;							\
+	HMT_MEDIUM_PPR_DISCARD;						\
 	SET_SCRATCH0(r13);    /* save r13 */				\
 	__EXCEPTION_PROLOG_1(PACA_EXGEN, extra, vec);		\
 	EXCEPTION_RELON_PROLOG_PSERIES_1(label##_common, h);
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 4e78247..886fc64 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -227,6 +227,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
 
 	beq-	1f
 	ACCOUNT_CPU_USER_EXIT(r11, r12)
+	HMT_MEDIUM_LOW_HAS_PPR
 	ld	r13,GPR13(r1)	/* only restore r13 if returning to usermode */
 1:	ld	r2,GPR2(r1)
 	ld	r1,GPR1(r1)
@@ -303,6 +304,7 @@ syscall_exit_work:
 	subi	r12,r12,TI_FLAGS
 
 4:	/* Anything else left to do? */
+	SET_DEFAULT_THREAD_PPR(r3, r9)		/* Set thread.ppr = 3 */
 	andi.	r0,r9,(_TIF_SYSCALL_T_OR_A|_TIF_SINGLESTEP)
 	beq	.ret_from_except_lite
 
@@ -764,6 +766,7 @@ fast_exception_return:
 	andi.	r0,r3,MSR_PR
 	beq	1f
 	ACCOUNT_CPU_USER_EXIT(r2, r4)
+	RESTORE_PPR(r2, r4)
 	REST_GPR(13, r1)
 1:
 	mtspr	SPRN_SRR1,r3
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 4665e82..6f9d83d 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -104,7 +104,7 @@ __start_interrupts:
 
 	.globl system_reset_pSeries;
 system_reset_pSeries:
-	HMT_MEDIUM;
+	HMT_MEDIUM_PPR_DISCARD
 	SET_SCRATCH0(r13)
 #ifdef CONFIG_PPC_P7_NAP
 BEGIN_FTR_SECTION
@@ -158,7 +158,7 @@ machine_check_pSeries_1:
 	. = 0x300
 	.globl data_access_pSeries
 data_access_pSeries:
-	HMT_MEDIUM
+	HMT_MEDIUM_PPR_DISCARD
 	SET_SCRATCH0(r13)
 BEGIN_FTR_SECTION
 	b	data_access_check_stab
@@ -170,7 +170,7 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_SLB)
 	. = 0x380
 	.globl data_access_slb_pSeries
 data_access_slb_pSeries:
-	HMT_MEDIUM
+	HMT_MEDIUM_PPR_DISCARD
 	SET_SCRATCH0(r13)
 	EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST, 0x380)
 	std	r3,PACA_EXSLB+EX_R3(r13)
@@ -201,7 +201,7 @@ data_access_slb_pSeries:
 	. = 0x480
 	.globl instruction_access_slb_pSeries
 instruction_access_slb_pSeries:
-	HMT_MEDIUM
+	HMT_MEDIUM_PPR_DISCARD
 	SET_SCRATCH0(r13)
 	EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x480)
 	std	r3,PACA_EXSLB+EX_R3(r13)
@@ -322,10 +322,11 @@ vsx_unavailable_pSeries_1:
 	. = 0x1500
 	.global denorm_exception_hv
 denorm_exception_hv:
-	HMT_MEDIUM
+	HMT_MEDIUM_PPR_DISCARD
 	mtspr	SPRN_SPRG_HSCRATCH0,r13
 	mfspr	r13,SPRN_SPRG_HPACA
 	std	r9,PACA_EXGEN+EX_R9(r13)
+	HMT_MEDIUM_PPR_SAVE(PACA_EXGEN, r9)
 	std	r10,PACA_EXGEN+EX_R10(r13)
 	std	r11,PACA_EXGEN+EX_R11(r13)
 	std	r12,PACA_EXGEN+EX_R12(r13)
@@ -367,7 +368,7 @@ denorm_exception_hv:
 machine_check_pSeries:
 	.globl machine_check_fwnmi
 machine_check_fwnmi:
-	HMT_MEDIUM
+	HMT_MEDIUM_PPR_DISCARD
 	SET_SCRATCH0(r13)		/* save r13 */
 	EXCEPTION_PROLOG_PSERIES(PACA_EXMC, machine_check_common,
 				 EXC_STD, KVMTEST, 0x200)
@@ -496,6 +497,7 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_206)
 	mtspr	SPRN_HSRR0,r11
 	mtcrf	0x80,r9
 	ld	r9,PACA_EXGEN+EX_R9(r13)
+	RESTORE_PPR_PACA(PACA_EXGEN, r10)
 	ld	r10,PACA_EXGEN+EX_R10(r13)
 	ld	r11,PACA_EXGEN+EX_R11(r13)
 	ld	r12,PACA_EXGEN+EX_R12(r13)
@@ -586,7 +588,7 @@ _GLOBAL(__replay_interrupt)
 	.globl system_reset_fwnmi
       .align 7
 system_reset_fwnmi:
-	HMT_MEDIUM
+	HMT_MEDIUM_PPR_DISCARD
 	SET_SCRATCH0(r13)		/* save r13 */
 	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common, EXC_STD,
 				 NOTEST, 0x100)
@@ -690,7 +692,7 @@ machine_check_common:
 	. = 0x4380
 	.globl data_access_slb_relon_pSeries
 data_access_slb_relon_pSeries:
-	HMT_MEDIUM
+	HMT_MEDIUM_PPR_DISCARD
 	SET_SCRATCH0(r13)
 	EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x380)
 	std	r3,PACA_EXSLB+EX_R3(r13)
@@ -715,7 +717,7 @@ data_access_slb_relon_pSeries:
 	. = 0x4480
 	.globl instruction_access_slb_relon_pSeries
 instruction_access_slb_relon_pSeries:
-	HMT_MEDIUM
+	HMT_MEDIUM_PPR_DISCARD
 	SET_SCRATCH0(r13)
 	EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x480)
 	std	r3,PACA_EXSLB+EX_R3(r13)
@@ -1036,6 +1038,7 @@ _GLOBAL(slb_miss_realmode)
 	mtcrf	0x01,r9		/* slb_allocate uses cr0 and cr7 */
 .machine	pop
 
+	RESTORE_PPR_PACA(PACA_EXSLB, r9)
 	ld	r9,PACA_EXSLB+EX_R9(r13)
 	ld	r10,PACA_EXSLB+EX_R10(r13)
 	ld	r11,PACA_EXSLB+EX_R11(r13)
@@ -1383,7 +1386,7 @@ initial_stab:
 
 #ifdef CONFIG_PPC_POWERNV
 _GLOBAL(opal_mc_secondary_handler)
-	HMT_MEDIUM
+	HMT_MEDIUM_PPR_DISCARD
 	SET_SCRATCH0(r13)
 	GET_PACA(r13)
 	clrldi	r3,r3,2