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

From: Christophe Leroy
Date: Sun Mar 29 2020 - 05:41:20 EST


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@xxxxxx>
---
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