kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.
Signed-off-by: Christophe Leroy <[email protected]>
Acked-by: Naveen N. Rao <[email protected]>
---
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
kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.
Signed-off-by: Christophe Leroy <[email protected]>
Acked-by: Naveen N. Rao <[email protected]>
---
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
kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.
Signed-off-by: Christophe Leroy <[email protected]>
Acked-by: Naveen N. Rao <[email protected]>
---
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
kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.
Signed-off-by: Christophe Leroy <[email protected]>
Acked-by: Naveen N. Rao <[email protected]>
---
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
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 <[email protected]>
Acked-by: Naveen N. Rao <[email protected]>
---
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
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 <[email protected]>
Acked-by: Naveen N. Rao <[email protected]>
---
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
kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.
Signed-off-by: Christophe Leroy <[email protected]>
Acked-by: Naveen N. Rao <[email protected]>
---
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
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 <[email protected]>
Acked-by: Naveen N. Rao <[email protected]>
---
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
kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.
Signed-off-by: Christophe Leroy <[email protected]>
Acked-by: Naveen N. Rao <[email protected]>
---
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
machine_check_in_rtas() is just a trap.
Do the trap directly in the machine check exception handler.
Signed-off-by: Christophe Leroy <[email protected]>
Acked-by: Naveen N. Rao <[email protected]>
---
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
kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.
Signed-off-by: Christophe Leroy <[email protected]>
Acked-by: Naveen N. Rao <[email protected]>
---
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
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 <[email protected]>
Acked-by: Naveen N. Rao <[email protected]>
---
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
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 <[email protected]>
> Acked-by: Naveen N. Rao <[email protected]>
> ---
> 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
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