* [PATCH 02/12] powerpc/82xx: Blacklist pq2_restart() for kprobe
2020-03-29 9:41 [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
@ 2020-03-29 9:41 ` Christophe Leroy
2020-03-29 9:41 ` [PATCH 03/12] powerpc/83xx: Blacklist mpc83xx_deep_resume() " Christophe Leroy
` (10 subsequent siblings)
11 siblings, 0 replies; 23+ messages in thread
From: Christophe Leroy @ 2020-03-29 9:41 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, naveen.n.rao
Cc: linux-kernel, linuxppc-dev
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>
---
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
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PATCH 03/12] powerpc/83xx: Blacklist mpc83xx_deep_resume() for kprobe
2020-03-29 9:41 [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
2020-03-29 9:41 ` [PATCH 02/12] powerpc/82xx: Blacklist pq2_restart() " Christophe Leroy
@ 2020-03-29 9:41 ` Christophe Leroy
2020-03-29 9:41 ` [PATCH 04/12] powerpc/powermac: Blacklist functions running with MMU disabled " Christophe Leroy
` (9 subsequent siblings)
11 siblings, 0 replies; 23+ messages in thread
From: Christophe Leroy @ 2020-03-29 9:41 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, naveen.n.rao
Cc: linux-kernel, linuxppc-dev
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>
---
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
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PATCH 04/12] powerpc/powermac: Blacklist functions running with MMU disabled for kprobe
2020-03-29 9:41 [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
2020-03-29 9:41 ` [PATCH 02/12] powerpc/82xx: Blacklist pq2_restart() " Christophe Leroy
2020-03-29 9:41 ` [PATCH 03/12] powerpc/83xx: Blacklist mpc83xx_deep_resume() " Christophe Leroy
@ 2020-03-29 9:41 ` Christophe Leroy
2020-03-29 9:41 ` [PATCH 05/12] powerpc/mem: Blacklist flush_dcache_icache_phys() " Christophe Leroy
` (8 subsequent siblings)
11 siblings, 0 replies; 23+ messages in thread
From: Christophe Leroy @ 2020-03-29 9:41 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, naveen.n.rao
Cc: linux-kernel, linuxppc-dev
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>
---
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
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PATCH 05/12] powerpc/mem: Blacklist flush_dcache_icache_phys() for kprobe
2020-03-29 9:41 [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
` (2 preceding siblings ...)
2020-03-29 9:41 ` [PATCH 04/12] powerpc/powermac: Blacklist functions running with MMU disabled " Christophe Leroy
@ 2020-03-29 9:41 ` Christophe Leroy
2020-03-29 9:41 ` [PATCH 06/12] powerpc/32s: Make local symbols non visible in hash_low Christophe Leroy
` (7 subsequent siblings)
11 siblings, 0 replies; 23+ messages in thread
From: Christophe Leroy @ 2020-03-29 9:41 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, naveen.n.rao
Cc: linux-kernel, linuxppc-dev
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>
---
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
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PATCH 06/12] powerpc/32s: Make local symbols non visible in hash_low.
2020-03-29 9:41 [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
` (3 preceding siblings ...)
2020-03-29 9:41 ` [PATCH 05/12] powerpc/mem: Blacklist flush_dcache_icache_phys() " Christophe Leroy
@ 2020-03-29 9:41 ` Christophe Leroy
2020-03-30 17:06 ` Naveen N. Rao
2020-03-29 9:41 ` [PATCH 07/12] powerpc/32s: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
` (6 subsequent siblings)
11 siblings, 1 reply; 23+ messages in thread
From: Christophe Leroy @ 2020-03-29 9:41 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, naveen.n.rao
Cc: linux-kernel, linuxppc-dev
In hash_low.S, a lot of named local symbols are used instead of
numbers to ease code lisibility. 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>
---
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
^ permalink raw reply related [flat|nested] 23+ messages in thread* Re: [PATCH 06/12] powerpc/32s: Make local symbols non visible in hash_low.
2020-03-29 9:41 ` [PATCH 06/12] powerpc/32s: Make local symbols non visible in hash_low Christophe Leroy
@ 2020-03-30 17:06 ` Naveen N. Rao
2020-03-30 17:22 ` Christophe Leroy
0 siblings, 1 reply; 23+ messages in thread
From: Naveen N. Rao @ 2020-03-30 17:06 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Christophe Leroy, Michael Ellerman,
Paul Mackerras
Cc: linux-kernel, linuxppc-dev
Christophe Leroy wrote:
> In hash_low.S, a lot of named local symbols are used instead of
> numbers to ease code lisibility. However, they don't need to be
^^^^^^^^^^
Nit.. visibility
- Naveen
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH 06/12] powerpc/32s: Make local symbols non visible in hash_low.
2020-03-30 17:06 ` Naveen N. Rao
@ 2020-03-30 17:22 ` Christophe Leroy
2020-03-30 17:49 ` Naveen N. Rao
0 siblings, 1 reply; 23+ messages in thread
From: Christophe Leroy @ 2020-03-30 17:22 UTC (permalink / raw)
To: Naveen N. Rao, Benjamin Herrenschmidt, Michael Ellerman, Paul Mackerras
Cc: linux-kernel, linuxppc-dev
Le 30/03/2020 à 19:06, Naveen N. Rao a écrit :
> Christophe Leroy wrote:
>> In hash_low.S, a lot of named local symbols are used instead of
>> numbers to ease code lisibility. However, they don't need to be
> ^^^^^^^^^^
> Nit.. visibility
Lol, no.
I mean't "lisibilité" in French, which means "readability"
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH 06/12] powerpc/32s: Make local symbols non visible in hash_low.
2020-03-30 17:22 ` Christophe Leroy
@ 2020-03-30 17:49 ` Naveen N. Rao
0 siblings, 0 replies; 23+ messages in thread
From: Naveen N. Rao @ 2020-03-30 17:49 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Christophe Leroy, Michael Ellerman,
Paul Mackerras
Cc: linux-kernel, linuxppc-dev
Christophe Leroy wrote:
>
>
> Le 30/03/2020 à 19:06, Naveen N. Rao a écrit :
>> Christophe Leroy wrote:
>>> In hash_low.S, a lot of named local symbols are used instead of
>>> numbers to ease code lisibility. However, they don't need to be
>> ^^^^^^^^^^
>> Nit.. visibility
>
>
> Lol, no.
>
> I mean't "lisibilité" in French, which means "readability"
Touche :D
- Naveen
^ permalink raw reply [flat|nested] 23+ messages in thread
* [PATCH 07/12] powerpc/32s: Blacklist functions running with MMU disabled for kprobe
2020-03-29 9:41 [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
` (4 preceding siblings ...)
2020-03-29 9:41 ` [PATCH 06/12] powerpc/32s: Make local symbols non visible in hash_low Christophe Leroy
@ 2020-03-29 9:41 ` Christophe Leroy
2020-03-29 9:41 ` [PATCH 08/12] powerpc/rtas: Remove machine_check_in_rtas() Christophe Leroy
` (5 subsequent siblings)
11 siblings, 0 replies; 23+ messages in thread
From: Christophe Leroy @ 2020-03-29 9:41 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, naveen.n.rao
Cc: linux-kernel, linuxppc-dev
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>
---
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
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PATCH 08/12] powerpc/rtas: Remove machine_check_in_rtas()
2020-03-29 9:41 [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
` (5 preceding siblings ...)
2020-03-29 9:41 ` [PATCH 07/12] powerpc/32s: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
@ 2020-03-29 9:41 ` Christophe Leroy
2020-03-29 9:41 ` [PATCH 09/12] powerpc/32: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
` (4 subsequent siblings)
11 siblings, 0 replies; 23+ messages in thread
From: Christophe Leroy @ 2020-03-29 9:41 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, naveen.n.rao
Cc: linux-kernel, linuxppc-dev
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>
---
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
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PATCH 09/12] powerpc/32: Blacklist functions running with MMU disabled for kprobe
2020-03-29 9:41 [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
` (6 preceding siblings ...)
2020-03-29 9:41 ` [PATCH 08/12] powerpc/rtas: Remove machine_check_in_rtas() Christophe Leroy
@ 2020-03-29 9:41 ` Christophe Leroy
2020-03-29 9:41 ` [PATCH 10/12] powerpc/entry32: Blacklist exception entry points " Christophe Leroy
` (3 subsequent siblings)
11 siblings, 0 replies; 23+ messages in thread
From: Christophe Leroy @ 2020-03-29 9:41 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, naveen.n.rao
Cc: linux-kernel, linuxppc-dev
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>
---
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 25c14a0981bf..403ab2c32dc8 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
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PATCH 10/12] powerpc/entry32: Blacklist exception entry points for kprobe.
2020-03-29 9:41 [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
` (7 preceding siblings ...)
2020-03-29 9:41 ` [PATCH 09/12] powerpc/32: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
@ 2020-03-29 9:41 ` Christophe Leroy
2020-03-30 17:08 ` Naveen N. Rao
2020-03-29 9:41 ` [PATCH 11/12] powerpc/entry32: Blacklist syscall exit " Christophe Leroy
` (2 subsequent siblings)
11 siblings, 1 reply; 23+ messages in thread
From: Christophe Leroy @ 2020-03-29 9:41 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, naveen.n.rao
Cc: linux-kernel, linuxppc-dev
kprobe does not handle events happening in real mode.
As exception entry points are running with MMU disabled,
blacklist them.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
arch/powerpc/kernel/entry_32.S | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 94f78c03cb79..9a1a45d6038a 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
@@ -286,6 +291,8 @@ reenable_mmu:
lwz r2, GPR2(r11)
b fast_exception_return
#endif
+_ASM_NOKPROBE_SYMBOL(transfer_to_handler)
+_ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont)
#ifndef CONFIG_VMAP_STACK
/*
--
2.25.0
^ permalink raw reply related [flat|nested] 23+ messages in thread* Re: [PATCH 10/12] powerpc/entry32: Blacklist exception entry points for kprobe.
2020-03-29 9:41 ` [PATCH 10/12] powerpc/entry32: Blacklist exception entry points " Christophe Leroy
@ 2020-03-30 17:08 ` Naveen N. Rao
2020-03-30 18:33 ` Christophe Leroy
0 siblings, 1 reply; 23+ messages in thread
From: Naveen N. Rao @ 2020-03-30 17:08 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Christophe Leroy, Michael Ellerman,
Paul Mackerras
Cc: linux-kernel, linuxppc-dev
Christophe Leroy wrote:
> kprobe does not handle events happening in real mode.
>
> As exception entry points are running with MMU disabled,
> blacklist them.
>
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
> ---
> arch/powerpc/kernel/entry_32.S | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
> index 94f78c03cb79..9a1a45d6038a 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
> @@ -286,6 +291,8 @@ reenable_mmu:
> lwz r2, GPR2(r11)
> b fast_exception_return
> #endif
> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler)
> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont)
These are added after 'reenable_mmu', which is itself not blacklisted.
Is that intentional?
- Naveen
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH 10/12] powerpc/entry32: Blacklist exception entry points for kprobe.
2020-03-30 17:08 ` Naveen N. Rao
@ 2020-03-30 18:33 ` Christophe Leroy
2020-03-31 5:51 ` Christophe Leroy
2020-03-31 6:13 ` Naveen N. Rao
0 siblings, 2 replies; 23+ messages in thread
From: Christophe Leroy @ 2020-03-30 18:33 UTC (permalink / raw)
To: Naveen N. Rao, Benjamin Herrenschmidt, Michael Ellerman, Paul Mackerras
Cc: linux-kernel, linuxppc-dev
Le 30/03/2020 à 19:08, Naveen N. Rao a écrit :
> Christophe Leroy wrote:
>> kprobe does not handle events happening in real mode.
>>
>> As exception entry points are running with MMU disabled,
>> blacklist them.
>>
>> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
>> ---
>> arch/powerpc/kernel/entry_32.S | 7 +++++++
>> 1 file changed, 7 insertions(+)
>>
>> diff --git a/arch/powerpc/kernel/entry_32.S
>> b/arch/powerpc/kernel/entry_32.S
>> index 94f78c03cb79..9a1a45d6038a 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
>> @@ -286,6 +291,8 @@ reenable_mmu:
>> lwz r2, GPR2(r11)
>> b fast_exception_return
>> #endif
>> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler)
>> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont)
>
> These are added after 'reenable_mmu', which is itself not blacklisted.
> Is that intentional?
Yes I put it as the complete end of the entry part, ie just before
stack_ovf which is a function by itself.
Note that reenable_mmu is inside an #ifdef CONFIG_TRACE_IRQFLAGS.
I'm not completely sure where to put the _ASM_NOKPROBE_SYMBOL()s, that's
the reason why I put it close to the symbol itself in my first series.
Could you have a look at the code and tell me what looks the most
appropriate as a location to you ?
https://elixir.bootlin.com/linux/v5.6/source/arch/powerpc/kernel/entry_32.S#L230
Thanks
Christophe
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH 10/12] powerpc/entry32: Blacklist exception entry points for kprobe.
2020-03-30 18:33 ` Christophe Leroy
@ 2020-03-31 5:51 ` Christophe Leroy
2020-03-31 6:17 ` Naveen N. Rao
2020-03-31 6:13 ` Naveen N. Rao
1 sibling, 1 reply; 23+ messages in thread
From: Christophe Leroy @ 2020-03-31 5:51 UTC (permalink / raw)
To: Naveen N. Rao, Benjamin Herrenschmidt, Michael Ellerman, Paul Mackerras
Cc: linuxppc-dev, linux-kernel
Le 30/03/2020 à 20:33, Christophe Leroy a écrit :
>
>
> Le 30/03/2020 à 19:08, Naveen N. Rao a écrit :
>> Christophe Leroy wrote:
>>> kprobe does not handle events happening in real mode.
>>>
>>> As exception entry points are running with MMU disabled,
>>> blacklist them.
>>>
>>> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
>>> ---
>>> arch/powerpc/kernel/entry_32.S | 7 +++++++
>>> 1 file changed, 7 insertions(+)
>>>
>>> diff --git a/arch/powerpc/kernel/entry_32.S
>>> b/arch/powerpc/kernel/entry_32.S
>>> index 94f78c03cb79..9a1a45d6038a 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
>>> @@ -286,6 +291,8 @@ reenable_mmu:
>>> lwz r2, GPR2(r11)
>>> b fast_exception_return
>>> #endif
>>> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler)
>>> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont)
>>
>> These are added after 'reenable_mmu', which is itself not blacklisted.
>> Is that intentional?
>
> Yes I put it as the complete end of the entry part, ie just before
> stack_ovf which is a function by itself.
>
> Note that reenable_mmu is inside an #ifdef CONFIG_TRACE_IRQFLAGS.
>
> I'm not completely sure where to put the _ASM_NOKPROBE_SYMBOL()s, that's
> the reason why I put it close to the symbol itself in my first series.
>
> Could you have a look at the code and tell me what looks the most
> appropriate as a location to you ?
>
> https://elixir.bootlin.com/linux/v5.6/source/arch/powerpc/kernel/entry_32.S#L230
Ok, thinking about it once more, I guess we have a problem as everything
after that reenable_mmu will be visible.
So I'll respin
Christophe
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH 10/12] powerpc/entry32: Blacklist exception entry points for kprobe.
2020-03-31 5:51 ` Christophe Leroy
@ 2020-03-31 6:17 ` Naveen N. Rao
2020-03-31 6:28 ` Christophe Leroy
0 siblings, 1 reply; 23+ messages in thread
From: Naveen N. Rao @ 2020-03-31 6:17 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Christophe Leroy, Michael Ellerman,
Paul Mackerras
Cc: linux-kernel, linuxppc-dev
Christophe Leroy wrote:
>
>
> Le 30/03/2020 à 20:33, Christophe Leroy a écrit :
>>
>>
>> Le 30/03/2020 à 19:08, Naveen N. Rao a écrit :
>>> Christophe Leroy wrote:
>>>> kprobe does not handle events happening in real mode.
>>>>
>>>> As exception entry points are running with MMU disabled,
>>>> blacklist them.
>>>>
>>>> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
>>>> ---
>>>> arch/powerpc/kernel/entry_32.S | 7 +++++++
>>>> 1 file changed, 7 insertions(+)
>>>>
>>>> diff --git a/arch/powerpc/kernel/entry_32.S
>>>> b/arch/powerpc/kernel/entry_32.S
>>>> index 94f78c03cb79..9a1a45d6038a 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
>>>> @@ -286,6 +291,8 @@ reenable_mmu:
>>>> lwz r2, GPR2(r11)
>>>> b fast_exception_return
>>>> #endif
>>>> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler)
>>>> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont)
>>>
>>> These are added after 'reenable_mmu', which is itself not blacklisted.
>>> Is that intentional?
>>
>> Yes I put it as the complete end of the entry part, ie just before
>> stack_ovf which is a function by itself.
>>
>> Note that reenable_mmu is inside an #ifdef CONFIG_TRACE_IRQFLAGS.
>>
>> I'm not completely sure where to put the _ASM_NOKPROBE_SYMBOL()s, that's
>> the reason why I put it close to the symbol itself in my first series.
>>
>> Could you have a look at the code and tell me what looks the most
>> appropriate as a location to you ?
>>
>> https://elixir.bootlin.com/linux/v5.6/source/arch/powerpc/kernel/entry_32.S#L230
>
> Ok, thinking about it once more, I guess we have a problem as everything
> after that reenable_mmu will be visible.
I see that we reach reenable_mmu through a 'rfi' with MSR_KERNEL, which
seems safe to me. So, I figured it can be probed without issues?
- Naveen
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH 10/12] powerpc/entry32: Blacklist exception entry points for kprobe.
2020-03-31 6:17 ` Naveen N. Rao
@ 2020-03-31 6:28 ` Christophe Leroy
2020-03-31 6:44 ` Naveen N. Rao
0 siblings, 1 reply; 23+ messages in thread
From: Christophe Leroy @ 2020-03-31 6:28 UTC (permalink / raw)
To: Naveen N. Rao, Benjamin Herrenschmidt, Michael Ellerman, Paul Mackerras
Cc: linux-kernel, linuxppc-dev
Le 31/03/2020 à 08:17, Naveen N. Rao a écrit :
> Christophe Leroy wrote:
>>
>>
>> Le 30/03/2020 à 20:33, Christophe Leroy a écrit :
>>>
>>>
>>> Le 30/03/2020 à 19:08, Naveen N. Rao a écrit :
>>>> Christophe Leroy wrote:
>>>>> kprobe does not handle events happening in real mode.
>>>>>
>>>>> As exception entry points are running with MMU disabled,
>>>>> blacklist them.
>>>>>
>>>>> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
>>>>> ---
>>>>> arch/powerpc/kernel/entry_32.S | 7 +++++++
>>>>> 1 file changed, 7 insertions(+)
>>>>>
>>>>> diff --git a/arch/powerpc/kernel/entry_32.S
>>>>> b/arch/powerpc/kernel/entry_32.S
>>>>> index 94f78c03cb79..9a1a45d6038a 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
>>>>> @@ -286,6 +291,8 @@ reenable_mmu:
>>>>> lwz r2, GPR2(r11)
>>>>> b fast_exception_return
>>>>> #endif
>>>>> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler)
>>>>> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont)
>>>>
>>>> These are added after 'reenable_mmu', which is itself not
>>>> blacklisted. Is that intentional?
>>>
>>> Yes I put it as the complete end of the entry part, ie just before
>>> stack_ovf which is a function by itself.
>>>
>>> Note that reenable_mmu is inside an #ifdef CONFIG_TRACE_IRQFLAGS.
>>>
>>> I'm not completely sure where to put the _ASM_NOKPROBE_SYMBOL()s,
>>> that's the reason why I put it close to the symbol itself in my first
>>> series.
>>>
>>> Could you have a look at the code and tell me what looks the most
>>> appropriate as a location to you ?
>>>
>>> https://elixir.bootlin.com/linux/v5.6/source/arch/powerpc/kernel/entry_32.S#L230
>>
>>
>> Ok, thinking about it once more, I guess we have a problem as
>> everything after that reenable_mmu will be visible.
>
> I see that we reach reenable_mmu through a 'rfi' with MSR_KERNEL, which
> seems safe to me. So, I figured it can be probed without issues?
Yes it can. And that's the reason why I didn't blacklist it. However the
4: and 7: which are after reenable_mmu are called from earlier, at a
time we are still in real mode. So I need to do something about that I
guess.
Christophe
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH 10/12] powerpc/entry32: Blacklist exception entry points for kprobe.
2020-03-31 6:28 ` Christophe Leroy
@ 2020-03-31 6:44 ` Naveen N. Rao
0 siblings, 0 replies; 23+ messages in thread
From: Naveen N. Rao @ 2020-03-31 6:44 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Christophe Leroy, Michael Ellerman,
Paul Mackerras
Cc: linux-kernel, linuxppc-dev
Christophe Leroy wrote:
>
>
> Le 31/03/2020 à 08:17, Naveen N. Rao a écrit :
>> Christophe Leroy wrote:
>>>
>>>
>>> Le 30/03/2020 à 20:33, Christophe Leroy a écrit :
>>>>
>>>>
>>>> Le 30/03/2020 à 19:08, Naveen N. Rao a écrit :
>>>>> Christophe Leroy wrote:
>>>>>> kprobe does not handle events happening in real mode.
>>>>>>
>>>>>> As exception entry points are running with MMU disabled,
>>>>>> blacklist them.
>>>>>>
>>>>>> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
>>>>>> ---
>>>>>> arch/powerpc/kernel/entry_32.S | 7 +++++++
>>>>>> 1 file changed, 7 insertions(+)
>>>>>>
>>>>>> diff --git a/arch/powerpc/kernel/entry_32.S
>>>>>> b/arch/powerpc/kernel/entry_32.S
>>>>>> index 94f78c03cb79..9a1a45d6038a 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
>>>>>> @@ -286,6 +291,8 @@ reenable_mmu:
>>>>>> lwz r2, GPR2(r11)
>>>>>> b fast_exception_return
>>>>>> #endif
>>>>>> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler)
>>>>>> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont)
>>>>>
>>>>> These are added after 'reenable_mmu', which is itself not
>>>>> blacklisted. Is that intentional?
>>>>
>>>> Yes I put it as the complete end of the entry part, ie just before
>>>> stack_ovf which is a function by itself.
>>>>
>>>> Note that reenable_mmu is inside an #ifdef CONFIG_TRACE_IRQFLAGS.
>>>>
>>>> I'm not completely sure where to put the _ASM_NOKPROBE_SYMBOL()s,
>>>> that's the reason why I put it close to the symbol itself in my first
>>>> series.
>>>>
>>>> Could you have a look at the code and tell me what looks the most
>>>> appropriate as a location to you ?
>>>>
>>>> https://elixir.bootlin.com/linux/v5.6/source/arch/powerpc/kernel/entry_32.S#L230
>>>
>>>
>>> Ok, thinking about it once more, I guess we have a problem as
>>> everything after that reenable_mmu will be visible.
>>
>> I see that we reach reenable_mmu through a 'rfi' with MSR_KERNEL, which
>> seems safe to me. So, I figured it can be probed without issues?
>
> Yes it can. And that's the reason why I didn't blacklist it. However the
> 4: and 7: which are after reenable_mmu are called from earlier, at a
> time we are still in real mode. So I need to do something about that I
> guess.
Ah yes, good catch. Makes sense to move 'reenable_mmu' after all.
Thanks,
Naveen
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH 10/12] powerpc/entry32: Blacklist exception entry points for kprobe.
2020-03-30 18:33 ` Christophe Leroy
2020-03-31 5:51 ` Christophe Leroy
@ 2020-03-31 6:13 ` Naveen N. Rao
1 sibling, 0 replies; 23+ messages in thread
From: Naveen N. Rao @ 2020-03-31 6:13 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Christophe Leroy, Michael Ellerman,
Paul Mackerras
Cc: linux-kernel, linuxppc-dev
Christophe Leroy wrote:
>
>
> Le 30/03/2020 à 19:08, Naveen N. Rao a écrit :
>> Christophe Leroy wrote:
>>> kprobe does not handle events happening in real mode.
>>>
>>> As exception entry points are running with MMU disabled,
>>> blacklist them.
>>>
>>> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
>>> ---
>>> arch/powerpc/kernel/entry_32.S | 7 +++++++
>>> 1 file changed, 7 insertions(+)
>>>
>>> diff --git a/arch/powerpc/kernel/entry_32.S
>>> b/arch/powerpc/kernel/entry_32.S
>>> index 94f78c03cb79..9a1a45d6038a 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
>>> @@ -286,6 +291,8 @@ reenable_mmu:
>>> lwz r2, GPR2(r11)
>>> b fast_exception_return
>>> #endif
>>> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler)
>>> +_ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont)
>>
>> These are added after 'reenable_mmu', which is itself not blacklisted.
>> Is that intentional?
>
> Yes I put it as the complete end of the entry part, ie just before
> stack_ovf which is a function by itself.
>
> Note that reenable_mmu is inside an #ifdef CONFIG_TRACE_IRQFLAGS.
>
> I'm not completely sure where to put the _ASM_NOKPROBE_SYMBOL()s, that's
> the reason why I put it close to the symbol itself in my first series.
Ok, I see what you mean. 'reenable_mmu' can probably be moved after the
end of 'transfer_to_handler_cont' (as also removing what looks to be an
unused label '1' for the branch to trace_hardirqs_off), but that's a
minor thing. From the blacklisting point, this is not an issue.
- Naveen
^ permalink raw reply [flat|nested] 23+ messages in thread
* [PATCH 11/12] powerpc/entry32: Blacklist syscall exit points for kprobe.
2020-03-29 9:41 [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
` (8 preceding siblings ...)
2020-03-29 9:41 ` [PATCH 10/12] powerpc/entry32: Blacklist exception entry points " Christophe Leroy
@ 2020-03-29 9:41 ` Christophe Leroy
2020-03-29 9:41 ` [PATCH 12/12] powerpc/entry32: Blacklist exception " Christophe Leroy
2020-03-30 17:13 ` [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled " Naveen N. Rao
11 siblings, 0 replies; 23+ messages in thread
From: Christophe Leroy @ 2020-03-29 9:41 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, naveen.n.rao
Cc: linux-kernel, linuxppc-dev
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>
---
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 9a1a45d6038a..7035e838d422 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
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PATCH 12/12] powerpc/entry32: Blacklist exception exit points for kprobe.
2020-03-29 9:41 [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
` (9 preceding siblings ...)
2020-03-29 9:41 ` [PATCH 11/12] powerpc/entry32: Blacklist syscall exit " Christophe Leroy
@ 2020-03-29 9:41 ` Christophe Leroy
2020-03-30 17:13 ` [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled " Naveen N. Rao
11 siblings, 0 replies; 23+ messages in thread
From: Christophe Leroy @ 2020-03-29 9:41 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, naveen.n.rao
Cc: linux-kernel, linuxppc-dev
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>
---
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 7035e838d422..e161fb7a0568 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
^ permalink raw reply related [flat|nested] 23+ messages in thread* Re: [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe
2020-03-29 9:41 [PATCH 01/12] powerpc/52xx: Blacklist functions running with MMU disabled for kprobe Christophe Leroy
` (10 preceding siblings ...)
2020-03-29 9:41 ` [PATCH 12/12] powerpc/entry32: Blacklist exception " Christophe Leroy
@ 2020-03-30 17:13 ` Naveen N. Rao
11 siblings, 0 replies; 23+ messages in thread
From: Naveen N. Rao @ 2020-03-30 17:13 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Christophe Leroy, Michael Ellerman,
Paul Mackerras
Cc: linux-kernel, linuxppc-dev
Christophe Leroy wrote:
> 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>
> ---
> arch/powerpc/platforms/52xx/lite5200_sleep.S | 2 ++
> 1 file changed, 2 insertions(+)
Apart from the two minor comments, for this series:
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
- Naveen
^ permalink raw reply [flat|nested] 23+ messages in thread