powerpc/32: Blacklist functions running with MMU disabled for kprobe

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>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3bf57066d05518644dee0840af69d36ab5086729.1585670437.git.christophe.leroy@c-s.fr

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)
 

arch/powerpc/kernel/entry_32.S

@@ -312,6 +312,7 @@ stack_ovf:
 	mtspr	SPRN_SRR1,r10
 	SYNC
 	RFI
+_ASM_NOKPROBE_SYMBOL(stack_ovf)
 #endif
 
 #ifdef CONFIG_TRACE_IRQFLAGS
@@ -1326,6 +1327,7 @@ nonrecoverable:
 	bl	unrecoverable_exception
 	/* shouldn't return */
 	b	4b
+_ASM_NOKPROBE_SYMBOL(nonrecoverable)
 
 	.section .bss
 	.align	2
@@ -1380,4 +1382,5 @@ _GLOBAL(enter_rtas)
 	mtspr	SPRN_SRR0,r8
 	mtspr	SPRN_SRR1,r9
 	RFI			/* return to caller */
+_ASM_NOKPROBE_SYMBOL(enter_rtas)
 #endif /* CONFIG_PPC_RTAS */

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)

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
 

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)

arch/powerpc/kernel/l2cr_6xx.S

@@ -455,5 +455,6 @@ _GLOBAL(__inval_enable_L1)
 	sync
 
  	blr
+_ASM_NOKPROBE_SYMBOL(__inval_enable_L1)
 
 

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

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 */
 

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)
 

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)