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.le...@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n....@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
