[PATCH v2 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe

[PATCH v2 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/52xx/lite5200_sleep.S | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/platforms/52xx/lite5200_sleep.S b/arch/powerpc/platforms/52xx/lite5200_sleep.S
index 3a9969c429b3..70083649c9ea 100644
--- a/arch/powerpc/platforms/52xx/lite5200_sleep.S
+++ b/arch/powerpc/platforms/52xx/lite5200_sleep.S
@@ -248,6 +248,7 @@ mmu_on:
 
 
 	blr
+_ASM_NOKPROBE_SYMBOL(lite5200_wakeup)
 
 
 /* ---------------------------------------------------------------------- */
@@ -391,6 +392,7 @@ restore_regs:
 	LOAD_SPRN(TBWU,  0x5b);
 
 	blr
+_ASM_NOKPROBE_SYMBOL(restore_regs)
 
 
 
-- 
2.25.0

[PATCH v2 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/52xx/lite5200_sleep.S | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/platforms/52xx/lite5200_sleep.S b/arch/powerpc/platforms/52xx/lite5200_sleep.S
index 3a9969c429b3..70083649c9ea 100644
--- a/arch/powerpc/platforms/52xx/lite5200_sleep.S
+++ b/arch/powerpc/platforms/52xx/lite5200_sleep.S
@@ -248,6 +248,7 @@ mmu_on:
 
 
 	blr
+_ASM_NOKPROBE_SYMBOL(lite5200_wakeup)
 
 
 /* ---------------------------------------------------------------------- */
@@ -391,6 +392,7 @@ restore_regs:
 	LOAD_SPRN(TBWU,  0x5b);
 
 	blr
+_ASM_NOKPROBE_SYMBOL(restore_regs)
 
 
 
-- 
2.25.0

[PATCH v2 02/12] powerpc/82xx: Blacklist pq2_restart() for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/82xx/pq2.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/powerpc/platforms/82xx/pq2.c b/arch/powerpc/platforms/82xx/pq2.c
index 1cdd5ed9d896..3b5cb39a564c 100644
--- a/arch/powerpc/platforms/82xx/pq2.c
+++ b/arch/powerpc/platforms/82xx/pq2.c
@@ -10,6 +10,8 @@
  * Copyright (c) 2006 MontaVista Software, Inc.
  */
 
+#include <linux/kprobes.h>
+
 #include <asm/cpm2.h>
 #include <asm/io.h>
 #include <asm/pci-bridge.h>
@@ -29,6 +31,7 @@ void __noreturn pq2_restart(char *cmd)
 
 	panic("Restart failed\n");
 }
+NOKPROBE_SYMBOL(pq2_restart)
 
 #ifdef CONFIG_PCI
 static int pq2_pci_exclude_device(struct pci_controller *hose,
-- 
2.25.0

[PATCH v2 02/12] powerpc/82xx: Blacklist pq2_restart() for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/82xx/pq2.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/powerpc/platforms/82xx/pq2.c b/arch/powerpc/platforms/82xx/pq2.c
index 1cdd5ed9d896..3b5cb39a564c 100644
--- a/arch/powerpc/platforms/82xx/pq2.c
+++ b/arch/powerpc/platforms/82xx/pq2.c
@@ -10,6 +10,8 @@
  * Copyright (c) 2006 MontaVista Software, Inc.
  */
 
+#include <linux/kprobes.h>
+
 #include <asm/cpm2.h>
 #include <asm/io.h>
 #include <asm/pci-bridge.h>
@@ -29,6 +31,7 @@ void __noreturn pq2_restart(char *cmd)
 
 	panic("Restart failed\n");
 }
+NOKPROBE_SYMBOL(pq2_restart)
 
 #ifdef CONFIG_PCI
 static int pq2_pci_exclude_device(struct pci_controller *hose,
-- 
2.25.0

[PATCH v2 03/12] powerpc/83xx: Blacklist mpc83xx_deep_resume() for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/83xx/suspend-asm.S | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/platforms/83xx/suspend-asm.S b/arch/powerpc/platforms/83xx/suspend-asm.S
index 3acd7470dc5e..bc6bd4d0ae96 100644
--- a/arch/powerpc/platforms/83xx/suspend-asm.S
+++ b/arch/powerpc/platforms/83xx/suspend-asm.S
@@ -548,3 +548,4 @@ mpc83xx_deep_resume:
 	mtdec	r0
 
 	rfi
+_ASM_NOKPROBE_SYMBOL(mpc83xx_deep_resume)
-- 
2.25.0

[PATCH v2 03/12] powerpc/83xx: Blacklist mpc83xx_deep_resume() for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/83xx/suspend-asm.S | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/platforms/83xx/suspend-asm.S b/arch/powerpc/platforms/83xx/suspend-asm.S
index 3acd7470dc5e..bc6bd4d0ae96 100644
--- a/arch/powerpc/platforms/83xx/suspend-asm.S
+++ b/arch/powerpc/platforms/83xx/suspend-asm.S
@@ -548,3 +548,4 @@ mpc83xx_deep_resume:
 	mtdec	r0
 
 	rfi
+_ASM_NOKPROBE_SYMBOL(mpc83xx_deep_resume)
-- 
2.25.0

[PATCH v2 04/12] powerpc/powermac: Blacklist functions running with MMU disabled for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powermac/cache.S | 2 ++
 arch/powerpc/platforms/powermac/sleep.S | 5 ++++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powermac/cache.S b/arch/powerpc/platforms/powermac/cache.S
index da69e0fcb4f1..ced225415486 100644
--- a/arch/powerpc/platforms/powermac/cache.S
+++ b/arch/powerpc/platforms/powermac/cache.S
@@ -184,6 +184,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 
 	mtlr	r10
 	blr
+_ASM_NOKPROBE_SYMBOL(flush_disable_75x)
 
 /* This code is for 745x processors */
 flush_disable_745x:
@@ -351,4 +352,5 @@ END_FTR_SECTION_IFSET(CPU_FTR_L3CR)
 	mtmsr	r11		/* restore DR and EE */
 	isync
 	blr
+_ASM_NOKPROBE_SYMBOL(flush_disable_745x)
 #endif	/* CONFIG_PPC_BOOK3S_32 */
diff --git a/arch/powerpc/platforms/powermac/sleep.S b/arch/powerpc/platforms/powermac/sleep.S
index bd6085b470b7..f9a680fdd9c4 100644
--- a/arch/powerpc/platforms/powermac/sleep.S
+++ b/arch/powerpc/platforms/powermac/sleep.S
@@ -244,7 +244,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_SPEC7450)
 	mtmsr	r2
 	isync
 	b	1b
-
+_ASM_NOKPROBE_SYMBOL(low_cpu_die)
 /*
  * Here is the resume code.
  */
@@ -282,6 +282,7 @@ _GLOBAL(core99_wake_up)
 	lwz	r1,0(r3)
 
 	/* Pass thru to older resume code ... */
+_ASM_NOKPROBE_SYMBOL(core99_wake_up)
 /*
  * Here is the resume code for older machines.
  * r1 has the physical address of SL_PC(sp).
@@ -429,6 +430,7 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
 	lwz	r0,4(r1)
 	mtlr	r0
 	blr
+_ASM_NOKPROBE_SYMBOL(grackle_wake_up)
 
 turn_on_mmu:
 	mflr	r4
@@ -438,6 +440,7 @@ turn_on_mmu:
 	sync
 	isync
 	rfi
+_ASM_NOKPROBE_SYMBOL(turn_on_mmu)
 
 #endif /* defined(CONFIG_PM) || defined(CONFIG_CPU_FREQ) */
 
-- 
2.25.0

[PATCH v2 04/12] powerpc/powermac: Blacklist functions running with MMU disabled for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powermac/cache.S | 2 ++
 arch/powerpc/platforms/powermac/sleep.S | 5 ++++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powermac/cache.S b/arch/powerpc/platforms/powermac/cache.S
index da69e0fcb4f1..ced225415486 100644
--- a/arch/powerpc/platforms/powermac/cache.S
+++ b/arch/powerpc/platforms/powermac/cache.S
@@ -184,6 +184,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 
 	mtlr	r10
 	blr
+_ASM_NOKPROBE_SYMBOL(flush_disable_75x)
 
 /* This code is for 745x processors */
 flush_disable_745x:
@@ -351,4 +352,5 @@ END_FTR_SECTION_IFSET(CPU_FTR_L3CR)
 	mtmsr	r11		/* restore DR and EE */
 	isync
 	blr
+_ASM_NOKPROBE_SYMBOL(flush_disable_745x)
 #endif	/* CONFIG_PPC_BOOK3S_32 */
diff --git a/arch/powerpc/platforms/powermac/sleep.S b/arch/powerpc/platforms/powermac/sleep.S
index bd6085b470b7..f9a680fdd9c4 100644
--- a/arch/powerpc/platforms/powermac/sleep.S
+++ b/arch/powerpc/platforms/powermac/sleep.S
@@ -244,7 +244,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_SPEC7450)
 	mtmsr	r2
 	isync
 	b	1b
-
+_ASM_NOKPROBE_SYMBOL(low_cpu_die)
 /*
  * Here is the resume code.
  */
@@ -282,6 +282,7 @@ _GLOBAL(core99_wake_up)
 	lwz	r1,0(r3)
 
 	/* Pass thru to older resume code ... */
+_ASM_NOKPROBE_SYMBOL(core99_wake_up)
 /*
  * Here is the resume code for older machines.
  * r1 has the physical address of SL_PC(sp).
@@ -429,6 +430,7 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
 	lwz	r0,4(r1)
 	mtlr	r0
 	blr
+_ASM_NOKPROBE_SYMBOL(grackle_wake_up)
 
 turn_on_mmu:
 	mflr	r4
@@ -438,6 +440,7 @@ turn_on_mmu:
 	sync
 	isync
 	rfi
+_ASM_NOKPROBE_SYMBOL(turn_on_mmu)
 
 #endif /* defined(CONFIG_PM) || defined(CONFIG_CPU_FREQ) */
 
-- 
2.25.0

[PATCH v2 05/12] powerpc/mem: Blacklist flush_dcache_icache_phys() for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/mm/mem.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 9b4f5fb719e0..bcb6af6ba29a 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -32,6 +32,7 @@
 #include <linux/vmalloc.h>
 #include <linux/memremap.h>
 #include <linux/dma-direct.h>
+#include <linux/kprobes.h>
 
 #include <asm/pgalloc.h>
 #include <asm/prom.h>
@@ -466,6 +467,7 @@ static void flush_dcache_icache_phys(unsigned long physaddr)
 		: "r" (nb), "r" (msr), "i" (bytes), "r" (msr0)
 		: "ctr", "memory");
 }
+NOKPROBE_SYMBOL(flush_dcache_icache_phys)
 #endif // !defined(CONFIG_PPC_8xx) && !defined(CONFIG_PPC64)
 
 /*
-- 
2.25.0

[PATCH v2 05/12] powerpc/mem: Blacklist flush_dcache_icache_phys() for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/mm/mem.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 9b4f5fb719e0..bcb6af6ba29a 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -32,6 +32,7 @@
 #include <linux/vmalloc.h>
 #include <linux/memremap.h>
 #include <linux/dma-direct.h>
+#include <linux/kprobes.h>
 
 #include <asm/pgalloc.h>
 #include <asm/prom.h>
@@ -466,6 +467,7 @@ static void flush_dcache_icache_phys(unsigned long physaddr)
 		: "r" (nb), "r" (msr), "i" (bytes), "r" (msr0)
 		: "ctr", "memory");
 }
+NOKPROBE_SYMBOL(flush_dcache_icache_phys)
 #endif // !defined(CONFIG_PPC_8xx) && !defined(CONFIG_PPC64)
 
 /*
-- 
2.25.0

[PATCH v2 06/12] powerpc/32s: Make local symbols non visible in hash_low.

[Christophe Leroy]

In hash_low.S, a lot of named local symbols are used instead of
numbers to ease code readability. However, they don't need to be
visible.

In order to ease blacklisting of functions running with MMU
disabled for kprobe, rename the symbols to .Lsymbols in order
to hide them as if they were numbered labels.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
v2: lisibility ==> readability
---
 arch/powerpc/mm/book3s32/hash_low.S | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/arch/powerpc/mm/book3s32/hash_low.S b/arch/powerpc/mm/book3s32/hash_low.S
index 6d236080cb1a..2afa3fa2012d 100644
--- a/arch/powerpc/mm/book3s32/hash_low.S
+++ b/arch/powerpc/mm/book3s32/hash_low.S
@@ -81,7 +81,7 @@ _GLOBAL(hash_page)
 	rlwinm.	r8,r8,0,0,20		/* extract pt base address */
 #endif
 #ifdef CONFIG_SMP
-	beq-	hash_page_out		/* return if no mapping */
+	beq-	.Lhash_page_out		/* return if no mapping */
 #else
 	/* XXX it seems like the 601 will give a machine fault on the
 	   rfi if its alignment is wrong (bottom 4 bits of address are
@@ -109,11 +109,11 @@ _GLOBAL(hash_page)
 #if (PTE_FLAGS_OFFSET != 0)
 	addi	r8,r8,PTE_FLAGS_OFFSET
 #endif
-retry:
+.Lretry:
 	lwarx	r6,0,r8			/* get linux-style pte, flag word */
 	andc.	r5,r3,r6		/* check access & ~permission */
 #ifdef CONFIG_SMP
-	bne-	hash_page_out		/* return if access not permitted */
+	bne-	.Lhash_page_out		/* return if access not permitted */
 #else
 	bnelr-
 #endif
@@ -128,7 +128,7 @@ retry:
 #endif /* CONFIG_SMP */
 #endif /* CONFIG_PTE_64BIT */
 	stwcx.	r5,0,r8			/* attempt to update PTE */
-	bne-	retry			/* retry if someone got there first */
+	bne-	.Lretry			/* retry if someone got there first */
 
 	mfsrin	r3,r4			/* get segment reg for segment */
 #ifndef CONFIG_VMAP_STACK
@@ -156,7 +156,7 @@ retry:
 #endif
 
 #ifdef CONFIG_SMP
-hash_page_out:
+.Lhash_page_out:
 	eieio
 	lis	r8, (mmu_hash_lock - PAGE_OFFSET)@ha
 	li	r0,0
@@ -358,7 +358,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
 1:	LDPTEu	r6,HPTE_SIZE(r4)	/* get next PTE */
 	CMPPTE	0,r6,r5
 	bdnzf	2,1b			/* loop while ctr != 0 && !cr0.eq */
-	beq+	found_slot
+	beq+	.Lfound_slot
 
 	patch_site	0f, patch__hash_page_B
 	/* Search the secondary PTEG for a matching PTE */
@@ -370,7 +370,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
 2:	LDPTEu	r6,HPTE_SIZE(r4)
 	CMPPTE	0,r6,r5
 	bdnzf	2,2b
-	beq+	found_slot
+	beq+	.Lfound_slot
 	xori	r5,r5,PTE_H		/* clear H bit again */
 
 	/* Search the primary PTEG for an empty slot */
@@ -379,7 +379,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
 1:	LDPTEu	r6,HPTE_SIZE(r4)	/* get next PTE */
 	TST_V(r6)			/* test valid bit */
 	bdnzf	2,1b			/* loop while ctr != 0 && !cr0.eq */
-	beq+	found_empty
+	beq+	.Lfound_empty
 
 	/* update counter of times that the primary PTEG is full */
 	lis	r4, (primary_pteg_full - PAGE_OFFSET)@ha
@@ -397,7 +397,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
 2:	LDPTEu	r6,HPTE_SIZE(r4)
 	TST_V(r6)
 	bdnzf	2,2b
-	beq+	found_empty
+	beq+	.Lfound_empty
 	xori	r5,r5,PTE_H		/* clear H bit again */
 
 	/*
@@ -435,9 +435,9 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
 
 #ifndef CONFIG_SMP
 	/* Store PTE in PTEG */
-found_empty:
+.Lfound_empty:
 	STPTE	r5,0(r4)
-found_slot:
+.Lfound_slot:
 	STPTE	r8,HPTE_SIZE/2(r4)
 
 #else /* CONFIG_SMP */
@@ -458,8 +458,8 @@ found_slot:
  * We do however have to make sure that the PTE is never in an invalid
  * state with the V bit set.
  */
-found_empty:
-found_slot:
+.Lfound_empty:
+.Lfound_slot:
 	CLR_V(r5,r0)		/* clear V (valid) bit in PTE */
 	STPTE	r5,0(r4)
 	sync
-- 
2.25.0

[PATCH v2 06/12] powerpc/32s: Make local symbols non visible in hash_low.

[Christophe Leroy]

In hash_low.S, a lot of named local symbols are used instead of
numbers to ease code readability. However, they don't need to be
visible.

In order to ease blacklisting of functions running with MMU
disabled for kprobe, rename the symbols to .Lsymbols in order
to hide them as if they were numbered labels.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
v2: lisibility ==> readability
---
 arch/powerpc/mm/book3s32/hash_low.S | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/arch/powerpc/mm/book3s32/hash_low.S b/arch/powerpc/mm/book3s32/hash_low.S
index 6d236080cb1a..2afa3fa2012d 100644
--- a/arch/powerpc/mm/book3s32/hash_low.S
+++ b/arch/powerpc/mm/book3s32/hash_low.S
@@ -81,7 +81,7 @@ _GLOBAL(hash_page)
 	rlwinm.	r8,r8,0,0,20		/* extract pt base address */
 #endif
 #ifdef CONFIG_SMP
-	beq-	hash_page_out		/* return if no mapping */
+	beq-	.Lhash_page_out		/* return if no mapping */
 #else
 	/* XXX it seems like the 601 will give a machine fault on the
 	   rfi if its alignment is wrong (bottom 4 bits of address are
@@ -109,11 +109,11 @@ _GLOBAL(hash_page)
 #if (PTE_FLAGS_OFFSET != 0)
 	addi	r8,r8,PTE_FLAGS_OFFSET
 #endif
-retry:
+.Lretry:
 	lwarx	r6,0,r8			/* get linux-style pte, flag word */
 	andc.	r5,r3,r6		/* check access & ~permission */
 #ifdef CONFIG_SMP
-	bne-	hash_page_out		/* return if access not permitted */
+	bne-	.Lhash_page_out		/* return if access not permitted */
 #else
 	bnelr-
 #endif
@@ -128,7 +128,7 @@ retry:
 #endif /* CONFIG_SMP */
 #endif /* CONFIG_PTE_64BIT */
 	stwcx.	r5,0,r8			/* attempt to update PTE */
-	bne-	retry			/* retry if someone got there first */
+	bne-	.Lretry			/* retry if someone got there first */
 
 	mfsrin	r3,r4			/* get segment reg for segment */
 #ifndef CONFIG_VMAP_STACK
@@ -156,7 +156,7 @@ retry:
 #endif
 
 #ifdef CONFIG_SMP
-hash_page_out:
+.Lhash_page_out:
 	eieio
 	lis	r8, (mmu_hash_lock - PAGE_OFFSET)@ha
 	li	r0,0
@@ -358,7 +358,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
 1:	LDPTEu	r6,HPTE_SIZE(r4)	/* get next PTE */
 	CMPPTE	0,r6,r5
 	bdnzf	2,1b			/* loop while ctr != 0 && !cr0.eq */
-	beq+	found_slot
+	beq+	.Lfound_slot
 
 	patch_site	0f, patch__hash_page_B
 	/* Search the secondary PTEG for a matching PTE */
@@ -370,7 +370,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
 2:	LDPTEu	r6,HPTE_SIZE(r4)
 	CMPPTE	0,r6,r5
 	bdnzf	2,2b
-	beq+	found_slot
+	beq+	.Lfound_slot
 	xori	r5,r5,PTE_H		/* clear H bit again */
 
 	/* Search the primary PTEG for an empty slot */
@@ -379,7 +379,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
 1:	LDPTEu	r6,HPTE_SIZE(r4)	/* get next PTE */
 	TST_V(r6)			/* test valid bit */
 	bdnzf	2,1b			/* loop while ctr != 0 && !cr0.eq */
-	beq+	found_empty
+	beq+	.Lfound_empty
 
 	/* update counter of times that the primary PTEG is full */
 	lis	r4, (primary_pteg_full - PAGE_OFFSET)@ha
@@ -397,7 +397,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
 2:	LDPTEu	r6,HPTE_SIZE(r4)
 	TST_V(r6)
 	bdnzf	2,2b
-	beq+	found_empty
+	beq+	.Lfound_empty
 	xori	r5,r5,PTE_H		/* clear H bit again */
 
 	/*
@@ -435,9 +435,9 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
 
 #ifndef CONFIG_SMP
 	/* Store PTE in PTEG */
-found_empty:
+.Lfound_empty:
 	STPTE	r5,0(r4)
-found_slot:
+.Lfound_slot:
 	STPTE	r8,HPTE_SIZE/2(r4)
 
 #else /* CONFIG_SMP */
@@ -458,8 +458,8 @@ found_slot:
  * We do however have to make sure that the PTE is never in an invalid
  * state with the V bit set.
  */
-found_empty:
-found_slot:
+.Lfound_empty:
+.Lfound_slot:
 	CLR_V(r5,r0)		/* clear V (valid) bit in PTE */
 	STPTE	r5,0(r4)
 	sync
-- 
2.25.0

[PATCH v2 07/12] powerpc/32s: Blacklist functions running with MMU disabled for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/mm/book3s32/hash_low.S | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/powerpc/mm/book3s32/hash_low.S b/arch/powerpc/mm/book3s32/hash_low.S
index 2afa3fa2012d..f5f836477009 100644
--- a/arch/powerpc/mm/book3s32/hash_low.S
+++ b/arch/powerpc/mm/book3s32/hash_low.S
@@ -163,6 +163,7 @@ _GLOBAL(hash_page)
 	stw	r0, (mmu_hash_lock - PAGE_OFFSET)@l(r8)
 	blr
 #endif /* CONFIG_SMP */
+_ASM_NOKPROBE_SYMBOL(hash_page)
 
 /*
  * Add an entry for a particular page to the hash table.
@@ -267,6 +268,7 @@ _GLOBAL(add_hash_page)
 	lwz	r0,4(r1)
 	mtlr	r0
 	blr
+_ASM_NOKPROBE_SYMBOL(add_hash_page)
 
 /*
  * This routine adds a hardware PTE to the hash table.
@@ -472,6 +474,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
 
 	sync		/* make sure pte updates get to memory */
 	blr
+_ASM_NOKPROBE_SYMBOL(create_hpte)
 
 	.section .bss
 	.align	2
@@ -628,6 +631,7 @@ _GLOBAL(flush_hash_pages)
 	isync
 	blr
 EXPORT_SYMBOL(flush_hash_pages)
+_ASM_NOKPROBE_SYMBOL(flush_hash_pages)
 
 /*
  * Flush an entry from the TLB
@@ -665,6 +669,7 @@ _GLOBAL(_tlbie)
 	sync
 #endif /* CONFIG_SMP */
 	blr
+_ASM_NOKPROBE_SYMBOL(_tlbie)
 
 /*
  * Flush the entire TLB. 603/603e only
@@ -706,3 +711,4 @@ _GLOBAL(_tlbia)
 	isync
 #endif /* CONFIG_SMP */
 	blr
+_ASM_NOKPROBE_SYMBOL(_tlbia)
-- 
2.25.0

[PATCH v2 07/12] powerpc/32s: Blacklist functions running with MMU disabled for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/mm/book3s32/hash_low.S | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/powerpc/mm/book3s32/hash_low.S b/arch/powerpc/mm/book3s32/hash_low.S
index 2afa3fa2012d..f5f836477009 100644
--- a/arch/powerpc/mm/book3s32/hash_low.S
+++ b/arch/powerpc/mm/book3s32/hash_low.S
@@ -163,6 +163,7 @@ _GLOBAL(hash_page)
 	stw	r0, (mmu_hash_lock - PAGE_OFFSET)@l(r8)
 	blr
 #endif /* CONFIG_SMP */
+_ASM_NOKPROBE_SYMBOL(hash_page)
 
 /*
  * Add an entry for a particular page to the hash table.
@@ -267,6 +268,7 @@ _GLOBAL(add_hash_page)
 	lwz	r0,4(r1)
 	mtlr	r0
 	blr
+_ASM_NOKPROBE_SYMBOL(add_hash_page)
 
 /*
  * This routine adds a hardware PTE to the hash table.
@@ -472,6 +474,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
 
 	sync		/* make sure pte updates get to memory */
 	blr
+_ASM_NOKPROBE_SYMBOL(create_hpte)
 
 	.section .bss
 	.align	2
@@ -628,6 +631,7 @@ _GLOBAL(flush_hash_pages)
 	isync
 	blr
 EXPORT_SYMBOL(flush_hash_pages)
+_ASM_NOKPROBE_SYMBOL(flush_hash_pages)
 
 /*
  * Flush an entry from the TLB
@@ -665,6 +669,7 @@ _GLOBAL(_tlbie)
 	sync
 #endif /* CONFIG_SMP */
 	blr
+_ASM_NOKPROBE_SYMBOL(_tlbie)
 
 /*
  * Flush the entire TLB. 603/603e only
@@ -706,3 +711,4 @@ _GLOBAL(_tlbia)
 	isync
 #endif /* CONFIG_SMP */
 	blr
+_ASM_NOKPROBE_SYMBOL(_tlbia)
-- 
2.25.0

[PATCH v2 08/12] powerpc/rtas: Remove machine_check_in_rtas()

[Christophe Leroy]

machine_check_in_rtas() is just a trap.

Do the trap directly in the machine check exception handler.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/entry_32.S | 6 ------
 arch/powerpc/kernel/head_32.S  | 2 +-
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index a6371fb8f761..e652f6506888 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -1391,10 +1391,4 @@ _GLOBAL(enter_rtas)
 	mtspr	SPRN_SRR0,r8
 	mtspr	SPRN_SRR1,r9
 	RFI			/* return to caller */
-
-	.globl	machine_check_in_rtas
-machine_check_in_rtas:
-	twi	31,0,0
-	/* XXX load up BATs and panic */
-
 #endif /* CONFIG_PPC_RTAS */
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index daaa153950c2..cbd30cac2496 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -297,7 +297,7 @@ MachineCheck:
 	cmpwi	cr1, r4, 0
 #endif
 	beq	cr1, machine_check_tramp
-	b	machine_check_in_rtas
+	twi	31, 0, 0
 #else
 	b	machine_check_tramp
 #endif
-- 
2.25.0

[PATCH v2 08/12] powerpc/rtas: Remove machine_check_in_rtas()

[Christophe Leroy]

machine_check_in_rtas() is just a trap.

Do the trap directly in the machine check exception handler.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/entry_32.S | 6 ------
 arch/powerpc/kernel/head_32.S  | 2 +-
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index a6371fb8f761..e652f6506888 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -1391,10 +1391,4 @@ _GLOBAL(enter_rtas)
 	mtspr	SPRN_SRR0,r8
 	mtspr	SPRN_SRR1,r9
 	RFI			/* return to caller */
-
-	.globl	machine_check_in_rtas
-machine_check_in_rtas:
-	twi	31,0,0
-	/* XXX load up BATs and panic */
-
 #endif /* CONFIG_PPC_RTAS */
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index daaa153950c2..cbd30cac2496 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -297,7 +297,7 @@ MachineCheck:
 	cmpwi	cr1, r4, 0
 #endif
 	beq	cr1, machine_check_tramp
-	b	machine_check_in_rtas
+	twi	31, 0, 0
 #else
 	b	machine_check_tramp
 #endif
-- 
2.25.0

[PATCH v2 09/12] powerpc/32: Blacklist functions running with MMU disabled for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/cpu_setup_6xx.S | 2 ++
 arch/powerpc/kernel/entry_32.S      | 3 +++
 arch/powerpc/kernel/fpu.S           | 1 +
 arch/powerpc/kernel/idle_6xx.S      | 1 +
 arch/powerpc/kernel/idle_e500.S     | 1 +
 arch/powerpc/kernel/l2cr_6xx.S      | 1 +
 arch/powerpc/kernel/misc.S          | 2 ++
 arch/powerpc/kernel/misc_32.S       | 2 ++
 arch/powerpc/kernel/swsusp_32.S     | 2 ++
 arch/powerpc/kernel/vector.S        | 1 +
 10 files changed, 16 insertions(+)

diff --git a/arch/powerpc/kernel/cpu_setup_6xx.S b/arch/powerpc/kernel/cpu_setup_6xx.S
index f6517f67265a..f8b5ff64b604 100644
--- a/arch/powerpc/kernel/cpu_setup_6xx.S
+++ b/arch/powerpc/kernel/cpu_setup_6xx.S
@@ -288,6 +288,7 @@ _GLOBAL(__init_fpu_registers)
 	mtmsr	r10
 	isync
 	blr
+_ASM_NOKPROBE_SYMBOL(__init_fpu_registers)
 
 
 /* Definitions for the table use to save CPU states */
@@ -483,4 +484,5 @@ _GLOBAL(__restore_cpu_setup)
 1:
 	mtcr	r7
 	blr
+_ASM_NOKPROBE_SYMBOL(__restore_cpu_setup)
 
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index e652f6506888..94f78c03cb79 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -313,6 +313,7 @@ stack_ovf:
 	mtspr	SPRN_SRR1,r10
 	SYNC
 	RFI
+_ASM_NOKPROBE_SYMBOL(stack_ovf)
 #endif
 
 #ifdef CONFIG_TRACE_IRQFLAGS
@@ -1337,6 +1338,7 @@ nonrecoverable:
 	bl	unrecoverable_exception
 	/* shouldn't return */
 	b	4b
+_ASM_NOKPROBE_SYMBOL(nonrecoverable)
 
 	.section .bss
 	.align	2
@@ -1391,4 +1393,5 @@ _GLOBAL(enter_rtas)
 	mtspr	SPRN_SRR0,r8
 	mtspr	SPRN_SRR1,r9
 	RFI			/* return to caller */
+_ASM_NOKPROBE_SYMBOL(enter_rtas)
 #endif /* CONFIG_PPC_RTAS */
diff --git a/arch/powerpc/kernel/fpu.S b/arch/powerpc/kernel/fpu.S
index 3235a8da6af7..1dfccf58fbb1 100644
--- a/arch/powerpc/kernel/fpu.S
+++ b/arch/powerpc/kernel/fpu.S
@@ -119,6 +119,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX)
 	/* restore registers and return */
 	/* we haven't used ctr or xer or lr */
 	blr
+_ASM_NOKPROBE_SYMBOL(load_up_fpu)
 
 /*
  * save_fpu(tsk)
diff --git a/arch/powerpc/kernel/idle_6xx.S b/arch/powerpc/kernel/idle_6xx.S
index 433d97bea1f3..69df840f7253 100644
--- a/arch/powerpc/kernel/idle_6xx.S
+++ b/arch/powerpc/kernel/idle_6xx.S
@@ -187,6 +187,7 @@ BEGIN_FTR_SECTION
 	mtspr	SPRN_HID1, r9
 END_FTR_SECTION_IFSET(CPU_FTR_DUAL_PLL_750FX)
 	b	transfer_to_handler_cont
+_ASM_NOKPROBE_SYMBOL(power_save_ppc32_restore)
 
 	.data
 
diff --git a/arch/powerpc/kernel/idle_e500.S b/arch/powerpc/kernel/idle_e500.S
index 308f499e146c..72c85b6f3898 100644
--- a/arch/powerpc/kernel/idle_e500.S
+++ b/arch/powerpc/kernel/idle_e500.S
@@ -90,3 +90,4 @@ _GLOBAL(power_save_ppc32_restore)
 #endif
 
 	b	transfer_to_handler_cont
+_ASM_NOKPROBE_SYMBOL(power_save_ppc32_restore)
diff --git a/arch/powerpc/kernel/l2cr_6xx.S b/arch/powerpc/kernel/l2cr_6xx.S
index 2020d255585f..5f07aa5e9851 100644
--- a/arch/powerpc/kernel/l2cr_6xx.S
+++ b/arch/powerpc/kernel/l2cr_6xx.S
@@ -455,5 +455,6 @@ _GLOBAL(__inval_enable_L1)
 	sync
 
  	blr
+_ASM_NOKPROBE_SYMBOL(__inval_enable_L1)
 
 
diff --git a/arch/powerpc/kernel/misc.S b/arch/powerpc/kernel/misc.S
index 65f9f731c229..5be96feccb55 100644
--- a/arch/powerpc/kernel/misc.S
+++ b/arch/powerpc/kernel/misc.S
@@ -36,6 +36,8 @@ _GLOBAL(add_reloc_offset)
 	add	r3,r3,r5
 	mtlr	r0
 	blr
+_ASM_NOKPROBE_SYMBOL(reloc_offset)
+_ASM_NOKPROBE_SYMBOL(add_reloc_offset)
 
 	.align	3
 2:	PPC_LONG 1b
diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index d80212be8698..1edcc41e15fc 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -246,6 +246,7 @@ _GLOBAL(real_readb)
 	sync
 	isync
 	blr
+_ASM_NOKPROBE_SYMBOL(real_readb)
 
 	/*
  * Do an IO access in real mode
@@ -263,6 +264,7 @@ _GLOBAL(real_writeb)
 	sync
 	isync
 	blr
+_ASM_NOKPROBE_SYMBOL(real_writeb)
 
 #endif /* CONFIG_40x */
 
diff --git a/arch/powerpc/kernel/swsusp_32.S b/arch/powerpc/kernel/swsusp_32.S
index cbdf86228eaa..f73f4d72fea4 100644
--- a/arch/powerpc/kernel/swsusp_32.S
+++ b/arch/powerpc/kernel/swsusp_32.S
@@ -395,6 +395,7 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
 
 	li	r3,0
 	blr
+_ASM_NOKPROBE_SYMBOL(swsusp_arch_resume)
 
 /* FIXME:This construct is actually not useful since we don't shut
  * down the instruction MMU, we could just flip back MSR-DR on.
@@ -406,4 +407,5 @@ turn_on_mmu:
 	sync
 	isync
 	rfi
+_ASM_NOKPROBE_SYMBOL(turn_on_mmu)
 
diff --git a/arch/powerpc/kernel/vector.S b/arch/powerpc/kernel/vector.S
index d20c5e79e03c..efc5b52f95d2 100644
--- a/arch/powerpc/kernel/vector.S
+++ b/arch/powerpc/kernel/vector.S
@@ -89,6 +89,7 @@ _GLOBAL(load_up_altivec)
 	REST_32VRS(0,r4,r6)
 	/* restore registers and return */
 	blr
+_ASM_NOKPROBE_SYMBOL(load_up_altivec)
 
 /*
  * save_altivec(tsk)
-- 
2.25.0

[PATCH v2 09/12] powerpc/32: Blacklist functions running with MMU disabled for kprobe

[Christophe Leroy]

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/cpu_setup_6xx.S | 2 ++
 arch/powerpc/kernel/entry_32.S      | 3 +++
 arch/powerpc/kernel/fpu.S           | 1 +
 arch/powerpc/kernel/idle_6xx.S      | 1 +
 arch/powerpc/kernel/idle_e500.S     | 1 +
 arch/powerpc/kernel/l2cr_6xx.S      | 1 +
 arch/powerpc/kernel/misc.S          | 2 ++
 arch/powerpc/kernel/misc_32.S       | 2 ++
 arch/powerpc/kernel/swsusp_32.S     | 2 ++
 arch/powerpc/kernel/vector.S        | 1 +
 10 files changed, 16 insertions(+)

diff --git a/arch/powerpc/kernel/cpu_setup_6xx.S b/arch/powerpc/kernel/cpu_setup_6xx.S
index f6517f67265a..f8b5ff64b604 100644
--- a/arch/powerpc/kernel/cpu_setup_6xx.S
+++ b/arch/powerpc/kernel/cpu_setup_6xx.S
@@ -288,6 +288,7 @@ _GLOBAL(__init_fpu_registers)
 	mtmsr	r10
 	isync
 	blr
+_ASM_NOKPROBE_SYMBOL(__init_fpu_registers)
 
 
 /* Definitions for the table use to save CPU states */
@@ -483,4 +484,5 @@ _GLOBAL(__restore_cpu_setup)
 1:
 	mtcr	r7
 	blr
+_ASM_NOKPROBE_SYMBOL(__restore_cpu_setup)
 
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index e652f6506888..94f78c03cb79 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -313,6 +313,7 @@ stack_ovf:
 	mtspr	SPRN_SRR1,r10
 	SYNC
 	RFI
+_ASM_NOKPROBE_SYMBOL(stack_ovf)
 #endif
 
 #ifdef CONFIG_TRACE_IRQFLAGS
@@ -1337,6 +1338,7 @@ nonrecoverable:
 	bl	unrecoverable_exception
 	/* shouldn't return */
 	b	4b
+_ASM_NOKPROBE_SYMBOL(nonrecoverable)
 
 	.section .bss
 	.align	2
@@ -1391,4 +1393,5 @@ _GLOBAL(enter_rtas)
 	mtspr	SPRN_SRR0,r8
 	mtspr	SPRN_SRR1,r9
 	RFI			/* return to caller */
+_ASM_NOKPROBE_SYMBOL(enter_rtas)
 #endif /* CONFIG_PPC_RTAS */
diff --git a/arch/powerpc/kernel/fpu.S b/arch/powerpc/kernel/fpu.S
index 3235a8da6af7..1dfccf58fbb1 100644
--- a/arch/powerpc/kernel/fpu.S
+++ b/arch/powerpc/kernel/fpu.S
@@ -119,6 +119,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX)
 	/* restore registers and return */
 	/* we haven't used ctr or xer or lr */
 	blr
+_ASM_NOKPROBE_SYMBOL(load_up_fpu)
 
 /*
  * save_fpu(tsk)
diff --git a/arch/powerpc/kernel/idle_6xx.S b/arch/powerpc/kernel/idle_6xx.S
index 433d97bea1f3..69df840f7253 100644
--- a/arch/powerpc/kernel/idle_6xx.S
+++ b/arch/powerpc/kernel/idle_6xx.S
@@ -187,6 +187,7 @@ BEGIN_FTR_SECTION
 	mtspr	SPRN_HID1, r9
 END_FTR_SECTION_IFSET(CPU_FTR_DUAL_PLL_750FX)
 	b	transfer_to_handler_cont
+_ASM_NOKPROBE_SYMBOL(power_save_ppc32_restore)
 
 	.data
 
diff --git a/arch/powerpc/kernel/idle_e500.S b/arch/powerpc/kernel/idle_e500.S
index 308f499e146c..72c85b6f3898 100644
--- a/arch/powerpc/kernel/idle_e500.S
+++ b/arch/powerpc/kernel/idle_e500.S
@@ -90,3 +90,4 @@ _GLOBAL(power_save_ppc32_restore)
 #endif
 
 	b	transfer_to_handler_cont
+_ASM_NOKPROBE_SYMBOL(power_save_ppc32_restore)
diff --git a/arch/powerpc/kernel/l2cr_6xx.S b/arch/powerpc/kernel/l2cr_6xx.S
index 2020d255585f..5f07aa5e9851 100644
--- a/arch/powerpc/kernel/l2cr_6xx.S
+++ b/arch/powerpc/kernel/l2cr_6xx.S
@@ -455,5 +455,6 @@ _GLOBAL(__inval_enable_L1)
 	sync
 
  	blr
+_ASM_NOKPROBE_SYMBOL(__inval_enable_L1)
 
 
diff --git a/arch/powerpc/kernel/misc.S b/arch/powerpc/kernel/misc.S
index 65f9f731c229..5be96feccb55 100644
--- a/arch/powerpc/kernel/misc.S
+++ b/arch/powerpc/kernel/misc.S
@@ -36,6 +36,8 @@ _GLOBAL(add_reloc_offset)
 	add	r3,r3,r5
 	mtlr	r0
 	blr
+_ASM_NOKPROBE_SYMBOL(reloc_offset)
+_ASM_NOKPROBE_SYMBOL(add_reloc_offset)
 
 	.align	3
 2:	PPC_LONG 1b
diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index d80212be8698..1edcc41e15fc 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -246,6 +246,7 @@ _GLOBAL(real_readb)
 	sync
 	isync
 	blr
+_ASM_NOKPROBE_SYMBOL(real_readb)
 
 	/*
  * Do an IO access in real mode
@@ -263,6 +264,7 @@ _GLOBAL(real_writeb)
 	sync
 	isync
 	blr
+_ASM_NOKPROBE_SYMBOL(real_writeb)
 
 #endif /* CONFIG_40x */
 
diff --git a/arch/powerpc/kernel/swsusp_32.S b/arch/powerpc/kernel/swsusp_32.S
index cbdf86228eaa..f73f4d72fea4 100644
--- a/arch/powerpc/kernel/swsusp_32.S
+++ b/arch/powerpc/kernel/swsusp_32.S
@@ -395,6 +395,7 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
 
 	li	r3,0
 	blr
+_ASM_NOKPROBE_SYMBOL(swsusp_arch_resume)
 
 /* FIXME:This construct is actually not useful since we don't shut
  * down the instruction MMU, we could just flip back MSR-DR on.
@@ -406,4 +407,5 @@ turn_on_mmu:
 	sync
 	isync
 	rfi
+_ASM_NOKPROBE_SYMBOL(turn_on_mmu)
 
diff --git a/arch/powerpc/kernel/vector.S b/arch/powerpc/kernel/vector.S
index d20c5e79e03c..efc5b52f95d2 100644
--- a/arch/powerpc/kernel/vector.S
+++ b/arch/powerpc/kernel/vector.S
@@ -89,6 +89,7 @@ _GLOBAL(load_up_altivec)
 	REST_32VRS(0,r4,r6)
 	/* restore registers and return */
 	blr
+_ASM_NOKPROBE_SYMBOL(load_up_altivec)
 
 /*
  * save_altivec(tsk)
-- 
2.25.0

[PATCH v2 10/12] powerpc/entry32: Blacklist exception entry points for kprobe.

[Christophe Leroy]

kprobe does not handle events happening in real mode.

As exception entry points are running with MMU disabled,
blacklist them.

The handling of TLF_NAPPING and TLF_SLEEPING is moved before the
CONFIG_TRACE_IRQFLAGS which contains 'reenable_mmu' because from there
kprobe will be possible as the kernel will run with MMU enabled.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
v2: Moved TLF_NAPPING and TLF_SLEEPING handling
---
 arch/powerpc/kernel/entry_32.S | 37 ++++++++++++++++++++--------------
 1 file changed, 22 insertions(+), 15 deletions(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 94f78c03cb79..215aa3a6d4f7 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -51,6 +51,7 @@ mcheck_transfer_to_handler:
 	mfspr	r0,SPRN_DSRR1
 	stw	r0,_DSRR1(r11)
 	/* fall through */
+_ASM_NOKPROBE_SYMBOL(mcheck_transfer_to_handler)
 
 	.globl	debug_transfer_to_handler
 debug_transfer_to_handler:
@@ -59,6 +60,7 @@ debug_transfer_to_handler:
 	mfspr	r0,SPRN_CSRR1
 	stw	r0,_CSRR1(r11)
 	/* fall through */
+_ASM_NOKPROBE_SYMBOL(debug_transfer_to_handler)
 
 	.globl	crit_transfer_to_handler
 crit_transfer_to_handler:
@@ -94,6 +96,7 @@ crit_transfer_to_handler:
 	rlwinm	r0,r1,0,0,(31 - THREAD_SHIFT)
 	stw	r0,KSP_LIMIT(r8)
 	/* fall through */
+_ASM_NOKPROBE_SYMBOL(crit_transfer_to_handler)
 #endif
 
 #ifdef CONFIG_40x
@@ -115,6 +118,7 @@ crit_transfer_to_handler:
 	rlwinm	r0,r1,0,0,(31 - THREAD_SHIFT)
 	stw	r0,KSP_LIMIT(r8)
 	/* fall through */
+_ASM_NOKPROBE_SYMBOL(crit_transfer_to_handler)
 #endif
 
 /*
@@ -127,6 +131,7 @@ crit_transfer_to_handler:
 	.globl	transfer_to_handler_full
 transfer_to_handler_full:
 	SAVE_NVGPRS(r11)
+_ASM_NOKPROBE_SYMBOL(transfer_to_handler_full)
 	/* fall through */
 
 	.globl	transfer_to_handler
@@ -227,6 +232,23 @@ transfer_to_handler_cont:
 	SYNC
 	RFI				/* jump to handler, enable MMU */
 
+#if defined (CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500)
+4:	rlwinm	r12,r12,0,~_TLF_NAPPING
+	stw	r12,TI_LOCAL_FLAGS(r2)
+	b	power_save_ppc32_restore
+
+7:	rlwinm	r12,r12,0,~_TLF_SLEEPING
+	stw	r12,TI_LOCAL_FLAGS(r2)
+	lwz	r9,_MSR(r11)		/* if sleeping, clear MSR.EE */
+	rlwinm	r9,r9,0,~MSR_EE
+	lwz	r12,_LINK(r11)		/* and return to address in LR */
+	kuap_restore r11, r2, r3, r4, r5
+	lwz	r2, GPR2(r11)
+	b	fast_exception_return
+#endif
+_ASM_NOKPROBE_SYMBOL(transfer_to_handler)
+_ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont)
+
 #ifdef CONFIG_TRACE_IRQFLAGS
 1:	/* MSR is changing, re-enable MMU so we can notify lockdep. We need to
 	 * keep interrupts disabled at this point otherwise we might risk
@@ -272,21 +294,6 @@ reenable_mmu:
 	bctr				/* jump to handler */
 #endif /* CONFIG_TRACE_IRQFLAGS */
 
-#if defined (CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500)
-4:	rlwinm	r12,r12,0,~_TLF_NAPPING
-	stw	r12,TI_LOCAL_FLAGS(r2)
-	b	power_save_ppc32_restore
-
-7:	rlwinm	r12,r12,0,~_TLF_SLEEPING
-	stw	r12,TI_LOCAL_FLAGS(r2)
-	lwz	r9,_MSR(r11)		/* if sleeping, clear MSR.EE */
-	rlwinm	r9,r9,0,~MSR_EE
-	lwz	r12,_LINK(r11)		/* and return to address in LR */
-	kuap_restore r11, r2, r3, r4, r5
-	lwz	r2, GPR2(r11)
-	b	fast_exception_return
-#endif
-
 #ifndef CONFIG_VMAP_STACK
 /*
  * On kernel stack overflow, load up an initial stack pointer
-- 
2.25.0

[PATCH v2 10/12] powerpc/entry32: Blacklist exception entry points for kprobe.

[Christophe Leroy]

kprobe does not handle events happening in real mode.

As exception entry points are running with MMU disabled,
blacklist them.

The handling of TLF_NAPPING and TLF_SLEEPING is moved before the
CONFIG_TRACE_IRQFLAGS which contains 'reenable_mmu' because from there
kprobe will be possible as the kernel will run with MMU enabled.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
v2: Moved TLF_NAPPING and TLF_SLEEPING handling
---
 arch/powerpc/kernel/entry_32.S | 37 ++++++++++++++++++++--------------
 1 file changed, 22 insertions(+), 15 deletions(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 94f78c03cb79..215aa3a6d4f7 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -51,6 +51,7 @@ mcheck_transfer_to_handler:
 	mfspr	r0,SPRN_DSRR1
 	stw	r0,_DSRR1(r11)
 	/* fall through */
+_ASM_NOKPROBE_SYMBOL(mcheck_transfer_to_handler)
 
 	.globl	debug_transfer_to_handler
 debug_transfer_to_handler:
@@ -59,6 +60,7 @@ debug_transfer_to_handler:
 	mfspr	r0,SPRN_CSRR1
 	stw	r0,_CSRR1(r11)
 	/* fall through */
+_ASM_NOKPROBE_SYMBOL(debug_transfer_to_handler)
 
 	.globl	crit_transfer_to_handler
 crit_transfer_to_handler:
@@ -94,6 +96,7 @@ crit_transfer_to_handler:
 	rlwinm	r0,r1,0,0,(31 - THREAD_SHIFT)
 	stw	r0,KSP_LIMIT(r8)
 	/* fall through */
+_ASM_NOKPROBE_SYMBOL(crit_transfer_to_handler)
 #endif
 
 #ifdef CONFIG_40x
@@ -115,6 +118,7 @@ crit_transfer_to_handler:
 	rlwinm	r0,r1,0,0,(31 - THREAD_SHIFT)
 	stw	r0,KSP_LIMIT(r8)
 	/* fall through */
+_ASM_NOKPROBE_SYMBOL(crit_transfer_to_handler)
 #endif
 
 /*
@@ -127,6 +131,7 @@ crit_transfer_to_handler:
 	.globl	transfer_to_handler_full
 transfer_to_handler_full:
 	SAVE_NVGPRS(r11)
+_ASM_NOKPROBE_SYMBOL(transfer_to_handler_full)
 	/* fall through */
 
 	.globl	transfer_to_handler
@@ -227,6 +232,23 @@ transfer_to_handler_cont:
 	SYNC
 	RFI				/* jump to handler, enable MMU */
 
+#if defined (CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500)
+4:	rlwinm	r12,r12,0,~_TLF_NAPPING
+	stw	r12,TI_LOCAL_FLAGS(r2)
+	b	power_save_ppc32_restore
+
+7:	rlwinm	r12,r12,0,~_TLF_SLEEPING
+	stw	r12,TI_LOCAL_FLAGS(r2)
+	lwz	r9,_MSR(r11)		/* if sleeping, clear MSR.EE */
+	rlwinm	r9,r9,0,~MSR_EE
+	lwz	r12,_LINK(r11)		/* and return to address in LR */
+	kuap_restore r11, r2, r3, r4, r5
+	lwz	r2, GPR2(r11)
+	b	fast_exception_return
+#endif
+_ASM_NOKPROBE_SYMBOL(transfer_to_handler)
+_ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont)
+
 #ifdef CONFIG_TRACE_IRQFLAGS
 1:	/* MSR is changing, re-enable MMU so we can notify lockdep. We need to
 	 * keep interrupts disabled at this point otherwise we might risk
@@ -272,21 +294,6 @@ reenable_mmu:
 	bctr				/* jump to handler */
 #endif /* CONFIG_TRACE_IRQFLAGS */
 
-#if defined (CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500)
-4:	rlwinm	r12,r12,0,~_TLF_NAPPING
-	stw	r12,TI_LOCAL_FLAGS(r2)
-	b	power_save_ppc32_restore
-
-7:	rlwinm	r12,r12,0,~_TLF_SLEEPING
-	stw	r12,TI_LOCAL_FLAGS(r2)
-	lwz	r9,_MSR(r11)		/* if sleeping, clear MSR.EE */
-	rlwinm	r9,r9,0,~MSR_EE
-	lwz	r12,_LINK(r11)		/* and return to address in LR */
-	kuap_restore r11, r2, r3, r4, r5
-	lwz	r2, GPR2(r11)
-	b	fast_exception_return
-#endif
-
 #ifndef CONFIG_VMAP_STACK
 /*
  * On kernel stack overflow, load up an initial stack pointer
-- 
2.25.0

[PATCH v2 11/12] powerpc/entry32: Blacklist syscall exit points for kprobe.

[Christophe Leroy]

kprobe does not handle events happening in real mode.

The very last part of syscall cannot support a trap.
Add a symbol syscall_exit_finish to identify that part and
blacklist it from kprobe.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/entry_32.S | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 215aa3a6d4f7..577d17fe0d94 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -463,6 +463,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX)
 	lwz	r7,_NIP(r1)
 	lwz	r2,GPR2(r1)
 	lwz	r1,GPR1(r1)
+syscall_exit_finish:
 #if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS)
 	mtspr	SPRN_NRI, r0
 #endif
@@ -470,6 +471,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX)
 	mtspr	SPRN_SRR1,r8
 	SYNC
 	RFI
+_ASM_NOKPROBE_SYMBOL(syscall_exit_finish)
 #ifdef CONFIG_44x
 2:	li	r7,0
 	iccci	r0,r0
@@ -604,6 +606,7 @@ ret_from_kernel_syscall:
 	mtspr	SPRN_SRR1, r10
 	SYNC
 	RFI
+_ASM_NOKPROBE_SYMBOL(ret_from_kernel_syscall)
 
 /*
  * The fork/clone functions need to copy the full register set into
-- 
2.25.0

[PATCH v2 11/12] powerpc/entry32: Blacklist syscall exit points for kprobe.

[Christophe Leroy]

kprobe does not handle events happening in real mode.

The very last part of syscall cannot support a trap.
Add a symbol syscall_exit_finish to identify that part and
blacklist it from kprobe.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/entry_32.S | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 215aa3a6d4f7..577d17fe0d94 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -463,6 +463,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX)
 	lwz	r7,_NIP(r1)
 	lwz	r2,GPR2(r1)
 	lwz	r1,GPR1(r1)
+syscall_exit_finish:
 #if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS)
 	mtspr	SPRN_NRI, r0
 #endif
@@ -470,6 +471,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX)
 	mtspr	SPRN_SRR1,r8
 	SYNC
 	RFI
+_ASM_NOKPROBE_SYMBOL(syscall_exit_finish)
 #ifdef CONFIG_44x
 2:	li	r7,0
 	iccci	r0,r0
@@ -604,6 +606,7 @@ ret_from_kernel_syscall:
 	mtspr	SPRN_SRR1, r10
 	SYNC
 	RFI
+_ASM_NOKPROBE_SYMBOL(ret_from_kernel_syscall)
 
 /*
  * The fork/clone functions need to copy the full register set into
-- 
2.25.0

[PATCH v2 12/12] powerpc/entry32: Blacklist exception exit points for kprobe.

[Christophe Leroy]

kprobe does not handle events happening in real mode.

The very last part of exception exits cannot support a trap.
Blacklist them from kprobe.

While we are at it, remove exc_exit_start symbol which is not
used to avoid having to blacklist it.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/entry_32.S | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 577d17fe0d94..02c81192ba52 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -810,6 +810,7 @@ fast_exception_return:
 	lwz	r11,GPR11(r11)
 	SYNC
 	RFI
+_ASM_NOKPROBE_SYMBOL(fast_exception_return)
 
 #if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE))
 /* check if the exception happened in a restartable section */
@@ -1049,6 +1050,8 @@ exc_exit_restart:
 exc_exit_restart_end:
 	SYNC
 	RFI
+_ASM_NOKPROBE_SYMBOL(exc_exit_restart)
+_ASM_NOKPROBE_SYMBOL(exc_exit_restart_end)
 
 #else /* !(CONFIG_4xx || CONFIG_BOOKE) */
 	/*
@@ -1070,7 +1073,6 @@ exc_exit_restart_end:
 exc_exit_restart:
 	lwz	r11,_NIP(r1)
 	lwz	r12,_MSR(r1)
-exc_exit_start:
 	mtspr	SPRN_SRR0,r11
 	mtspr	SPRN_SRR1,r12
 	REST_2GPRS(11, r1)
@@ -1080,6 +1082,7 @@ exc_exit_restart_end:
 	PPC405_ERR77_SYNC
 	rfi
 	b	.			/* prevent prefetch past rfi */
+_ASM_NOKPROBE_SYMBOL(exc_exit_restart)
 
 /*
  * Returning from a critical interrupt in user mode doesn't need
@@ -1193,6 +1196,7 @@ ret_from_crit_exc:
 	mtspr	SPRN_SRR0,r9;
 	mtspr	SPRN_SRR1,r10;
 	RET_FROM_EXC_LEVEL(SPRN_CSRR0, SPRN_CSRR1, PPC_RFCI)
+_ASM_NOKPROBE_SYMBOL(ret_from_crit_exc)
 #endif /* CONFIG_40x */
 
 #ifdef CONFIG_BOOKE
@@ -1204,6 +1208,7 @@ ret_from_crit_exc:
 	RESTORE_xSRR(SRR0,SRR1);
 	RESTORE_MMU_REGS;
 	RET_FROM_EXC_LEVEL(SPRN_CSRR0, SPRN_CSRR1, PPC_RFCI)
+_ASM_NOKPROBE_SYMBOL(ret_from_crit_exc)
 
 	.globl	ret_from_debug_exc
 ret_from_debug_exc:
@@ -1214,6 +1219,7 @@ ret_from_debug_exc:
 	RESTORE_xSRR(CSRR0,CSRR1);
 	RESTORE_MMU_REGS;
 	RET_FROM_EXC_LEVEL(SPRN_DSRR0, SPRN_DSRR1, PPC_RFDI)
+_ASM_NOKPROBE_SYMBOL(ret_from_debug_exc)
 
 	.globl	ret_from_mcheck_exc
 ret_from_mcheck_exc:
@@ -1225,6 +1231,7 @@ ret_from_mcheck_exc:
 	RESTORE_xSRR(DSRR0,DSRR1);
 	RESTORE_MMU_REGS;
 	RET_FROM_EXC_LEVEL(SPRN_MCSRR0, SPRN_MCSRR1, PPC_RFMCI)
+_ASM_NOKPROBE_SYMBOL(ret_from_mcheck_exc)
 #endif /* CONFIG_BOOKE */
 
 /*
-- 
2.25.0

[PATCH v2 12/12] powerpc/entry32: Blacklist exception exit points for kprobe.

[Christophe Leroy]

kprobe does not handle events happening in real mode.

The very last part of exception exits cannot support a trap.
Blacklist them from kprobe.

While we are at it, remove exc_exit_start symbol which is not
used to avoid having to blacklist it.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/entry_32.S | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 577d17fe0d94..02c81192ba52 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -810,6 +810,7 @@ fast_exception_return:
 	lwz	r11,GPR11(r11)
 	SYNC
 	RFI
+_ASM_NOKPROBE_SYMBOL(fast_exception_return)
 
 #if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE))
 /* check if the exception happened in a restartable section */
@@ -1049,6 +1050,8 @@ exc_exit_restart:
 exc_exit_restart_end:
 	SYNC
 	RFI
+_ASM_NOKPROBE_SYMBOL(exc_exit_restart)
+_ASM_NOKPROBE_SYMBOL(exc_exit_restart_end)
 
 #else /* !(CONFIG_4xx || CONFIG_BOOKE) */
 	/*
@@ -1070,7 +1073,6 @@ exc_exit_restart_end:
 exc_exit_restart:
 	lwz	r11,_NIP(r1)
 	lwz	r12,_MSR(r1)
-exc_exit_start:
 	mtspr	SPRN_SRR0,r11
 	mtspr	SPRN_SRR1,r12
 	REST_2GPRS(11, r1)
@@ -1080,6 +1082,7 @@ exc_exit_restart_end:
 	PPC405_ERR77_SYNC
 	rfi
 	b	.			/* prevent prefetch past rfi */
+_ASM_NOKPROBE_SYMBOL(exc_exit_restart)
 
 /*
  * Returning from a critical interrupt in user mode doesn't need
@@ -1193,6 +1196,7 @@ ret_from_crit_exc:
 	mtspr	SPRN_SRR0,r9;
 	mtspr	SPRN_SRR1,r10;
 	RET_FROM_EXC_LEVEL(SPRN_CSRR0, SPRN_CSRR1, PPC_RFCI)
+_ASM_NOKPROBE_SYMBOL(ret_from_crit_exc)
 #endif /* CONFIG_40x */
 
 #ifdef CONFIG_BOOKE
@@ -1204,6 +1208,7 @@ ret_from_crit_exc:
 	RESTORE_xSRR(SRR0,SRR1);
 	RESTORE_MMU_REGS;
 	RET_FROM_EXC_LEVEL(SPRN_CSRR0, SPRN_CSRR1, PPC_RFCI)
+_ASM_NOKPROBE_SYMBOL(ret_from_crit_exc)
 
 	.globl	ret_from_debug_exc
 ret_from_debug_exc:
@@ -1214,6 +1219,7 @@ ret_from_debug_exc:
 	RESTORE_xSRR(CSRR0,CSRR1);
 	RESTORE_MMU_REGS;
 	RET_FROM_EXC_LEVEL(SPRN_DSRR0, SPRN_DSRR1, PPC_RFDI)
+_ASM_NOKPROBE_SYMBOL(ret_from_debug_exc)
 
 	.globl	ret_from_mcheck_exc
 ret_from_mcheck_exc:
@@ -1225,6 +1231,7 @@ ret_from_mcheck_exc:
 	RESTORE_xSRR(DSRR0,DSRR1);
 	RESTORE_MMU_REGS;
 	RET_FROM_EXC_LEVEL(SPRN_MCSRR0, SPRN_MCSRR1, PPC_RFMCI)
+_ASM_NOKPROBE_SYMBOL(ret_from_mcheck_exc)
 #endif /* CONFIG_BOOKE */
 
 /*
-- 
2.25.0

Re: [PATCH v2 10/12] powerpc/entry32: Blacklist exception entry points for kprobe.

[Naveen N. Rao]

Christophe Leroy wrote:
> kprobe does not handle events happening in real mode.
> 
> As exception entry points are running with MMU disabled,
> blacklist them.
> 
> The handling of TLF_NAPPING and TLF_SLEEPING is moved before the
> CONFIG_TRACE_IRQFLAGS which contains 'reenable_mmu' because from there
> kprobe will be possible as the kernel will run with MMU enabled.
> 
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
> ---
> v2: Moved TLF_NAPPING and TLF_SLEEPING handling
> ---
>  arch/powerpc/kernel/entry_32.S | 37 ++++++++++++++++++++--------------
>  1 file changed, 22 insertions(+), 15 deletions(-)
> 
> diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
> index 94f78c03cb79..215aa3a6d4f7 100644
> --- a/arch/powerpc/kernel/entry_32.S
> +++ b/arch/powerpc/kernel/entry_32.S
> @@ -51,6 +51,7 @@ mcheck_transfer_to_handler:
>  	mfspr	r0,SPRN_DSRR1
>  	stw	r0,_DSRR1(r11)
>  	/* fall through */
> +_ASM_NOKPROBE_SYMBOL(mcheck_transfer_to_handler)
> 
>  	.globl	debug_transfer_to_handler
>  debug_transfer_to_handler:
> @@ -59,6 +60,7 @@ debug_transfer_to_handler:
>  	mfspr	r0,SPRN_CSRR1
>  	stw	r0,_CSRR1(r11)
>  	/* fall through */
> +_ASM_NOKPROBE_SYMBOL(debug_transfer_to_handler)
> 
>  	.globl	crit_transfer_to_handler
>  crit_transfer_to_handler:
> @@ -94,6 +96,7 @@ crit_transfer_to_handler:
>  	rlwinm	r0,r1,0,0,(31 - THREAD_SHIFT)
>  	stw	r0,KSP_LIMIT(r8)
>  	/* fall through */
> +_ASM_NOKPROBE_SYMBOL(crit_transfer_to_handler)
>  #endif
> 
>  #ifdef CONFIG_40x
> @@ -115,6 +118,7 @@ crit_transfer_to_handler:
>  	rlwinm	r0,r1,0,0,(31 - THREAD_SHIFT)
>  	stw	r0,KSP_LIMIT(r8)
>  	/* fall through */
> +_ASM_NOKPROBE_SYMBOL(crit_transfer_to_handler)
>  #endif
> 
>  /*
> @@ -127,6 +131,7 @@ crit_transfer_to_handler:
>  	.globl	transfer_to_handler_full
>  transfer_to_handler_full:
>  	SAVE_NVGPRS(r11)
> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler_full)
>  	/* fall through */
> 
>  	.globl	transfer_to_handler
> @@ -227,6 +232,23 @@ transfer_to_handler_cont:
>  	SYNC
>  	RFI				/* jump to handler, enable MMU */
> 
> +#if defined (CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500)
> +4:	rlwinm	r12,r12,0,~_TLF_NAPPING
> +	stw	r12,TI_LOCAL_FLAGS(r2)
> +	b	power_save_ppc32_restore
> +
> +7:	rlwinm	r12,r12,0,~_TLF_SLEEPING
> +	stw	r12,TI_LOCAL_FLAGS(r2)
> +	lwz	r9,_MSR(r11)		/* if sleeping, clear MSR.EE */
> +	rlwinm	r9,r9,0,~MSR_EE
> +	lwz	r12,_LINK(r11)		/* and return to address in LR */
> +	kuap_restore r11, r2, r3, r4, r5
> +	lwz	r2, GPR2(r11)
> +	b	fast_exception_return
> +#endif
> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler)
> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont)
> +

A very minor nit is that the above NOKPROBE annotation actually covers 
the block of code below between the label '1:' till 'reenable_mmu', but 
isn't obvious from the code. Splitting off 'reenable_mmu' would have 
made that clear.

You don't have to fix that though -- a kprobe still won't be allowed 
there and anyone interested should be able to look up this mail chain.


- Naveen

Re: [PATCH v2 10/12] powerpc/entry32: Blacklist exception entry points for kprobe.

[Naveen N. Rao]

Christophe Leroy wrote:
> kprobe does not handle events happening in real mode.
> 
> As exception entry points are running with MMU disabled,
> blacklist them.
> 
> The handling of TLF_NAPPING and TLF_SLEEPING is moved before the
> CONFIG_TRACE_IRQFLAGS which contains 'reenable_mmu' because from there
> kprobe will be possible as the kernel will run with MMU enabled.
> 
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
> ---
> v2: Moved TLF_NAPPING and TLF_SLEEPING handling
> ---
>  arch/powerpc/kernel/entry_32.S | 37 ++++++++++++++++++++--------------
>  1 file changed, 22 insertions(+), 15 deletions(-)
> 
> diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
> index 94f78c03cb79..215aa3a6d4f7 100644
> --- a/arch/powerpc/kernel/entry_32.S
> +++ b/arch/powerpc/kernel/entry_32.S
> @@ -51,6 +51,7 @@ mcheck_transfer_to_handler:
>  	mfspr	r0,SPRN_DSRR1
>  	stw	r0,_DSRR1(r11)
>  	/* fall through */
> +_ASM_NOKPROBE_SYMBOL(mcheck_transfer_to_handler)
> 
>  	.globl	debug_transfer_to_handler
>  debug_transfer_to_handler:
> @@ -59,6 +60,7 @@ debug_transfer_to_handler:
>  	mfspr	r0,SPRN_CSRR1
>  	stw	r0,_CSRR1(r11)
>  	/* fall through */
> +_ASM_NOKPROBE_SYMBOL(debug_transfer_to_handler)
> 
>  	.globl	crit_transfer_to_handler
>  crit_transfer_to_handler:
> @@ -94,6 +96,7 @@ crit_transfer_to_handler:
>  	rlwinm	r0,r1,0,0,(31 - THREAD_SHIFT)
>  	stw	r0,KSP_LIMIT(r8)
>  	/* fall through */
> +_ASM_NOKPROBE_SYMBOL(crit_transfer_to_handler)
>  #endif
> 
>  #ifdef CONFIG_40x
> @@ -115,6 +118,7 @@ crit_transfer_to_handler:
>  	rlwinm	r0,r1,0,0,(31 - THREAD_SHIFT)
>  	stw	r0,KSP_LIMIT(r8)
>  	/* fall through */
> +_ASM_NOKPROBE_SYMBOL(crit_transfer_to_handler)
>  #endif
> 
>  /*
> @@ -127,6 +131,7 @@ crit_transfer_to_handler:
>  	.globl	transfer_to_handler_full
>  transfer_to_handler_full:
>  	SAVE_NVGPRS(r11)
> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler_full)
>  	/* fall through */
> 
>  	.globl	transfer_to_handler
> @@ -227,6 +232,23 @@ transfer_to_handler_cont:
>  	SYNC
>  	RFI				/* jump to handler, enable MMU */
> 
> +#if defined (CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500)
> +4:	rlwinm	r12,r12,0,~_TLF_NAPPING
> +	stw	r12,TI_LOCAL_FLAGS(r2)
> +	b	power_save_ppc32_restore
> +
> +7:	rlwinm	r12,r12,0,~_TLF_SLEEPING
> +	stw	r12,TI_LOCAL_FLAGS(r2)
> +	lwz	r9,_MSR(r11)		/* if sleeping, clear MSR.EE */
> +	rlwinm	r9,r9,0,~MSR_EE
> +	lwz	r12,_LINK(r11)		/* and return to address in LR */
> +	kuap_restore r11, r2, r3, r4, r5
> +	lwz	r2, GPR2(r11)
> +	b	fast_exception_return
> +#endif
> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler)
> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont)
> +

A very minor nit is that the above NOKPROBE annotation actually covers 
the block of code below between the label '1:' till 'reenable_mmu', but 
isn't obvious from the code. Splitting off 'reenable_mmu' would have 
made that clear.

You don't have to fix that though -- a kprobe still won't be allowed 
there and anyone interested should be able to look up this mail chain.


- Naveen

Re: [PATCH v2 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe

[Michael Ellerman]

On Tue, 31 Mar 2020 16:03:36 +0000 (UTC), Christophe Leroy wrote:
> kprobe does not handle events happening in real mode, all
> functions running with MMU disabled have to be blacklisted.

Applied to powerpc/next.

[01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe
        https://git.kernel.org/powerpc/c/e83f01fdb9143a4f90b17fbf7d8b8b21efb2f968
[02/12] powerpc/82xx: Blacklist pq2_restart() for kprobe
        https://git.kernel.org/powerpc/c/1740f15a99d30a5e2710b2b0754e65fc5ba68d1d
[03/12] powerpc/83xx: Blacklist mpc83xx_deep_resume() for kprobe
        https://git.kernel.org/powerpc/c/7aa85127b1a170694b042cbc35a07afe3904173e
[04/12] powerpc/powermac: Blacklist functions running with MMU disabled for kprobe
        https://git.kernel.org/powerpc/c/32a820670fa00419375a964ca8bc569e1499b90d
[05/12] powerpc/mem: Blacklist flush_dcache_icache_phys() for kprobe
        https://git.kernel.org/powerpc/c/a64371b5d4fb37199dcd04cb7bf0132894018e33
[06/12] powerpc/32s: Make local symbols non visible in hash_low.
        https://git.kernel.org/powerpc/c/f892c21d2efb3b86ecbf8f5a95ea4abeedcc91b0
[07/12] powerpc/32s: Blacklist functions running with MMU disabled for kprobe
        https://git.kernel.org/powerpc/c/e6209318d63e2774c5ab214b14b948079e040064
[08/12] powerpc/rtas: Remove machine_check_in_rtas()
        https://git.kernel.org/powerpc/c/32746dfe4cf37f4077929601e8877a7fd02676e8
[09/12] powerpc/32: Blacklist functions running with MMU disabled for kprobe
        https://git.kernel.org/powerpc/c/5f32e8361cba8c58c4f272a389296f489ecc2823
[10/12] powerpc/entry32: Blacklist exception entry points for kprobe.
        https://git.kernel.org/powerpc/c/a616c442119f2ea5641e6abc215d7255b73b982b
[11/12] powerpc/entry32: Blacklist syscall exit points for kprobe.
        https://git.kernel.org/powerpc/c/7cdf4401388572f720403a7038a178a4b30ac14c
[12/12] powerpc/entry32: Blacklist exception exit points for kprobe.
        https://git.kernel.org/powerpc/c/e51c3e13709fe55d4d0eb50ba435bc53a64152bf

cheers