Commit 719e7e21 authored Mar 12, 2021 by Christophe Leroy Committed by Michael Ellerman Mar 29, 2021

powerpc/32: Save trap number on stack in exception prolog

Saving the trap number into the stack goes into
the exception prolog, as EXC_XFER_xxx will soon disappear.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2ac7a0c9cde2ec2b23cd79e3a54cfedd816a91ae.1615552867.git.christophe.leroy@csgroup.eu

parent af6f2ce8

arch/powerpc/kernel/head_32.h

+7 −7

Original line number	Diff line number	Diff line
		@@ -10,10 +10,10 @@
		* We assume sprg3 has the physical address of the current
		* task's thread_struct.
		*/
		.macro EXCEPTION_PROLOG name handle_dar_dsisr=0
		.macro EXCEPTION_PROLOG trapno name handle_dar_dsisr=0
		EXCEPTION_PROLOG_0 handle_dar_dsisr=\handle_dar_dsisr
		EXCEPTION_PROLOG_1
		EXCEPTION_PROLOG_2 \name handle_dar_dsisr=\handle_dar_dsisr
		EXCEPTION_PROLOG_2 \trapno \name handle_dar_dsisr=\handle_dar_dsisr
		.endm

		.macro EXCEPTION_PROLOG_0 handle_dar_dsisr=0
		@@ -56,7 +56,7 @@
		#endif
		.endm

		.macro EXCEPTION_PROLOG_2 name handle_dar_dsisr=0
		.macro EXCEPTION_PROLOG_2 trapno name handle_dar_dsisr=0
		#ifdef CONFIG_PPC_8xx
		.if \handle_dar_dsisr
		li r11, RPN_PATTERN
		@@ -108,6 +108,8 @@
		lis r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
		addi r10,r10,STACK_FRAME_REGS_MARKER@l
		stw r10,8(r11)
		li r10, \trapno
		stw r10,_TRAP(r11)
		SAVE_4GPRS(3, r11)
		SAVE_2GPRS(7, r11)
		_ASM_NOKPROBE_SYMBOL(\name\()_virt)
		@@ -182,12 +184,10 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)

		#define EXCEPTION(n, label, hdlr, xfer) \
		START_EXCEPTION(n, label) \
		EXCEPTION_PROLOG label; \
		EXCEPTION_PROLOG n label; \
		xfer(n, hdlr)

		#define EXC_XFER_TEMPLATE(hdlr, trap, msr, tfer, ret) \
		li r10,trap; \
		stw r10,_TRAP(r11); \
		bl tfer; \
		bl hdlr; \
		b ret
		@@ -213,7 +213,7 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
		#endif
		lwz r1, emergency_ctx@l(r1)
		addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE
		EXCEPTION_PROLOG_2 vmap_stack_overflow
		EXCEPTION_PROLOG_2 0 vmap_stack_overflow
		EXC_XFER_STD(0, stack_overflow_exception)
		.endm

arch/powerpc/kernel/head_40x.S

+12 −10

Original line number	Diff line number	Diff line
		@@ -104,7 +104,7 @@ _ENTRY(crit_esr)
		* Instead we use a couple of words of memory at low physical addresses.
		* This is OK since we don't support SMP on these processors.
		*/
		.macro CRITICAL_EXCEPTION_PROLOG name
		.macro CRITICAL_EXCEPTION_PROLOG trapno name
		stw r10,crit_r10@l(0) /* save two registers to work with */
		stw r11,crit_r11@l(0)
		mfspr r10,SPRN_SRR0
		@@ -161,6 +161,8 @@ _ENTRY(crit_esr)
		lis r10, STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
		addi r10, r10, STACK_FRAME_REGS_MARKER@l
		stw r10, 8(r11)
		li r10, \trapno + 2
		stw r10,_TRAP(r11)
		SAVE_4GPRS(3, r11)
		SAVE_2GPRS(7, r11)
		_ASM_NOKPROBE_SYMBOL(\name\()_virt)
		@@ -184,7 +186,7 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
		*/
		#define CRITICAL_EXCEPTION(n, label, hdlr) \
		START_EXCEPTION(n, label); \
		CRITICAL_EXCEPTION_PROLOG label; \
		CRITICAL_EXCEPTION_PROLOG n label; \
		EXC_XFER_TEMPLATE(hdlr, n+2, (MSR_KERNEL & ~(MSR_ME\|MSR_DE\|MSR_CE)), \
		crit_transfer_to_handler, ret_from_crit_exc)

		@@ -206,7 +208,7 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
		* if they can't resolve the lightweight TLB fault.
		*/
		START_EXCEPTION(0x0300, DataStorage)
		EXCEPTION_PROLOG DataStorage handle_dar_dsisr=1
		EXCEPTION_PROLOG 0x300 DataStorage handle_dar_dsisr=1
		EXC_XFER_LITE(0x300, do_page_fault)

		/*
		@@ -214,7 +216,7 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
		* This is caused by a fetch from non-execute or guarded pages.
		*/
		START_EXCEPTION(0x0400, InstructionAccess)
		EXCEPTION_PROLOG InstructionAccess
		EXCEPTION_PROLOG 0x400 InstructionAccess
		li r5,0
		stw r5, _ESR(r11) /* Zero ESR */
		stw r12, _DEAR(r11) /* SRR0 as DEAR */
		@@ -225,12 +227,12 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)

		/* 0x0600 - Alignment Exception */
		START_EXCEPTION(0x0600, Alignment)
		EXCEPTION_PROLOG Alignment handle_dar_dsisr=1
		EXCEPTION_PROLOG 0x600 Alignment handle_dar_dsisr=1
		EXC_XFER_STD(0x600, alignment_exception)

		/* 0x0700 - Program Exception */
		START_EXCEPTION(0x0700, ProgramCheck)
		EXCEPTION_PROLOG ProgramCheck handle_dar_dsisr=1
		EXCEPTION_PROLOG 0x700 ProgramCheck handle_dar_dsisr=1
		EXC_XFER_STD(0x700, program_check_exception)

		EXCEPTION(0x0800, Trap_08, unknown_exception, EXC_XFER_STD)
		@@ -449,7 +451,7 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
		*/
		/* 0x2000 - Debug Exception */
		START_EXCEPTION(0x2000, DebugTrap)
		CRITICAL_EXCEPTION_PROLOG DebugTrap
		CRITICAL_EXCEPTION_PROLOG 0x2000 DebugTrap

		/*
		* If this is a single step or branch-taken exception in an
		@@ -498,7 +500,7 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
		/* Programmable Interval Timer (PIT) Exception. (from 0x1000) */
		__HEAD
		Decrementer:
		EXCEPTION_PROLOG Decrementer
		EXCEPTION_PROLOG 0x1000 Decrementer
		lis r0,TSR_PIS@h
		mtspr SPRN_TSR,r0 /* Clear the PIT exception */
		EXC_XFER_LITE(0x1000, timer_interrupt)
		@@ -506,13 +508,13 @@ Decrementer:
		/* Fixed Interval Timer (FIT) Exception. (from 0x1010) */
		__HEAD
		FITException:
		EXCEPTION_PROLOG FITException
		EXCEPTION_PROLOG 0x1010 FITException
		EXC_XFER_STD(0x1010, unknown_exception)

		/* Watchdog Timer (WDT) Exception. (from 0x1020) */
		__HEAD
		WDTException:
		CRITICAL_EXCEPTION_PROLOG WDTException
		CRITICAL_EXCEPTION_PROLOG 0x1020 WDTException
		EXC_XFER_TEMPLATE(WatchdogException, 0x1020+2,
		(MSR_KERNEL & ~(MSR_ME\|MSR_DE\|MSR_CE)),
		crit_transfer_to_handler, ret_from_crit_exc)

arch/powerpc/kernel/head_8xx.S

+7 −7

Original line number	Diff line number	Diff line
		@@ -122,7 +122,7 @@ instruction_counter:

		/* Machine check */
		START_EXCEPTION(0x200, MachineCheck)
		EXCEPTION_PROLOG MachineCheck handle_dar_dsisr=1
		EXCEPTION_PROLOG 0x200 MachineCheck handle_dar_dsisr=1
		EXC_XFER_STD(0x200, machine_check_exception)

		/* External interrupt */
		@@ -130,7 +130,7 @@ instruction_counter:

		/* Alignment exception */
		START_EXCEPTION(0x600, Alignment)
		EXCEPTION_PROLOG Alignment handle_dar_dsisr=1
		EXCEPTION_PROLOG 0x600 Alignment handle_dar_dsisr=1
		EXC_XFER_STD(0x600, alignment_exception)

		/* Program check exception */
		@@ -292,12 +292,12 @@ instruction_counter:
		* addresses. There is nothing to do but handle a big time error fault.
		*/
		START_EXCEPTION(0x1300, InstructionTLBError)
		EXCEPTION_PROLOG InstructionTLBError
		/* 0x400 is InstructionAccess exception, needed by bad_page_fault() */
		EXCEPTION_PROLOG 0x400 InstructionTLBError
		andis. r5,r9,DSISR_SRR1_MATCH_32S@h /* Filter relevant SRR1 bits */
		andis. r10,r9,SRR1_ISI_NOPT@h
		beq+ .Litlbie
		tlbie r12
		/* 0x400 is InstructionAccess exception, needed by bad_page_fault() */
		.Litlbie:
		stw r12, _DAR(r11)
		stw r5, _DSISR(r11)
		@@ -314,14 +314,14 @@ instruction_counter:
		beq- cr1, FixupDAR /* must be a buggy dcbX, icbi insn. */
		DARFixed:/* Return from dcbx instruction bug workaround */
		EXCEPTION_PROLOG_1
		EXCEPTION_PROLOG_2 DataTLBError handle_dar_dsisr=1
		/* 0x300 is DataAccess exception, needed by bad_page_fault() */
		EXCEPTION_PROLOG_2 0x300 DataTLBError handle_dar_dsisr=1
		lwz r4, _DAR(r11)
		lwz r5, _DSISR(r11)
		andis. r10,r5,DSISR_NOHPTE@h
		beq+ .Ldtlbie
		tlbie r4
		.Ldtlbie:
		/* 0x300 is DataAccess exception, needed by bad_page_fault() */
		EXC_XFER_LITE(0x300, do_page_fault)

		#ifdef CONFIG_VMAP_STACK
		@@ -345,7 +345,7 @@ DARFixed:/* Return from dcbx instruction bug workaround */
		rfi

		1: EXCEPTION_PROLOG_1
		EXCEPTION_PROLOG_2 DataBreakpoint handle_dar_dsisr=1
		EXCEPTION_PROLOG_2 0x1c00 DataBreakpoint handle_dar_dsisr=1
		mfspr r4,SPRN_BAR
		stw r4,_DAR(r11)
		EXC_XFER_STD(0x1c00, do_break)

arch/powerpc/kernel/head_book3s_32.S

+7 −7

Original line number	Diff line number	Diff line
		@@ -266,7 +266,7 @@ __secondary_hold_acknowledge:
		mfspr r1, SPRN_SPRG_SCRATCH2
		#endif /* CONFIG_PPC_CHRP */
		EXCEPTION_PROLOG_1
		7: EXCEPTION_PROLOG_2 MachineCheck
		7: EXCEPTION_PROLOG_2 0x200 MachineCheck
		#ifdef CONFIG_PPC_CHRP
		beq cr1, 1f
		twi 31, 0, 0
		@@ -295,7 +295,7 @@ ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_HPTE_TABLE)
		#endif
		1: EXCEPTION_PROLOG_0 handle_dar_dsisr=1
		EXCEPTION_PROLOG_1
		EXCEPTION_PROLOG_2 DataAccess handle_dar_dsisr=1
		EXCEPTION_PROLOG_2 0x300 DataAccess handle_dar_dsisr=1
		lwz r5, _DSISR(r11)
		andis. r0, r5, DSISR_DABRMATCH@h
		bne- 1f
		@@ -324,7 +324,7 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE)
		andi. r11, r11, MSR_PR

		EXCEPTION_PROLOG_1
		EXCEPTION_PROLOG_2 InstructionAccess
		EXCEPTION_PROLOG_2 0x400 InstructionAccess
		andis. r5,r9,DSISR_SRR1_MATCH_32S@h /* Filter relevant SRR1 bits */
		stw r5, _DSISR(r11)
		stw r12, _DAR(r11)
		@@ -335,7 +335,7 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE)

		/* Alignment exception */
		START_EXCEPTION(0x600, Alignment)
		EXCEPTION_PROLOG Alignment handle_dar_dsisr=1
		EXCEPTION_PROLOG 0x600 Alignment handle_dar_dsisr=1
		EXC_XFER_STD(0x600, alignment_exception)

		/* Program check exception */
		@@ -351,7 +351,7 @@ BEGIN_FTR_SECTION
		*/
		b ProgramCheck
		END_FTR_SECTION_IFSET(CPU_FTR_FPU_UNAVAILABLE)
		EXCEPTION_PROLOG FPUnavailable
		EXCEPTION_PROLOG 0x800 FPUnavailable
		beq 1f
		bl load_up_fpu /* if from user, just load it up */
		b fast_exception_return
		@@ -713,7 +713,7 @@ fast_hash_page_return:

		__HEAD
		AltiVecUnavailable:
		EXCEPTION_PROLOG AltiVecUnavailable
		EXCEPTION_PROLOG 0xf20 AltiVecUnavailable
		#ifdef CONFIG_ALTIVEC
		beq 1f
		bl load_up_altivec /* if from user, just load it up */
		@@ -723,7 +723,7 @@ AltiVecUnavailable:

		__HEAD
		PerformanceMonitor:
		EXCEPTION_PROLOG PerformanceMonitor
		EXCEPTION_PROLOG 0xf00 PerformanceMonitor
		EXC_XFER_STD(0xf00, performance_monitor_exception)

arch/powerpc/kernel/head_booke.h

+23 −21

Original line number	Diff line number	Diff line
		@@ -44,7 +44,7 @@ END_BTB_FLUSH_SECTION
		#endif


		#define NORMAL_EXCEPTION_PROLOG(intno) \
		#define NORMAL_EXCEPTION_PROLOG(trapno, intno) \
		mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \
		mfspr r10, SPRN_SPRG_THREAD; \
		stw r11, THREAD_NORMSAVE(0)(r10); \
		@@ -82,6 +82,8 @@ END_BTB_FLUSH_SECTION
		lis r10, STACK_FRAME_REGS_MARKER@ha;/* exception frame marker */ \
		addi r10, r10, STACK_FRAME_REGS_MARKER@l; \
		stw r10, 8(r11); \
		li r10, trapno; \
		stw r10,_TRAP(r11); \
		SAVE_4GPRS(3, r11); \
		SAVE_2GPRS(7, r11)

		@@ -182,7 +184,7 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
		* registers as the normal prolog above. Instead we use a portion of the
		* critical/machine check exception stack at low physical addresses.
		*/
		#define EXC_LEVEL_EXCEPTION_PROLOG(exc_level, intno, exc_level_srr0, exc_level_srr1) \
		#define EXC_LEVEL_EXCEPTION_PROLOG(exc_level, trapno, intno, exc_level_srr0, exc_level_srr1) \
		mtspr SPRN_SPRG_WSCRATCH_##exc_level,r8; \
		BOOKE_LOAD_EXC_LEVEL_STACK(exc_level);/* r8 points to the exc_level stack*/ \
		stw r9,GPR9(r8); /* save various registers */\
		@@ -225,6 +227,8 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
		stw r1,0(r11); \
		mr r1,r11; \
		rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\
		li r10, trapno; \
		stw r10,_TRAP(r11); \
		stw r0,GPR0(r11); \
		SAVE_4GPRS(3, r11); \
		SAVE_2GPRS(7, r11)
		@@ -259,12 +263,12 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
		#endif
		.endm

		#define CRITICAL_EXCEPTION_PROLOG(intno) \
		EXC_LEVEL_EXCEPTION_PROLOG(CRIT, intno, SPRN_CSRR0, SPRN_CSRR1)
		#define DEBUG_EXCEPTION_PROLOG \
		EXC_LEVEL_EXCEPTION_PROLOG(DBG, DEBUG, SPRN_DSRR0, SPRN_DSRR1)
		#define MCHECK_EXCEPTION_PROLOG \
		EXC_LEVEL_EXCEPTION_PROLOG(MC, MACHINE_CHECK, \
		#define CRITICAL_EXCEPTION_PROLOG(trapno, intno) \
		EXC_LEVEL_EXCEPTION_PROLOG(CRIT, trapno+2, intno, SPRN_CSRR0, SPRN_CSRR1)
		#define DEBUG_EXCEPTION_PROLOG(trapno) \
		EXC_LEVEL_EXCEPTION_PROLOG(DBG, trapno+8, DEBUG, SPRN_DSRR0, SPRN_DSRR1)
		#define MCHECK_EXCEPTION_PROLOG(trapno) \
		EXC_LEVEL_EXCEPTION_PROLOG(MC, trapno+4, MACHINE_CHECK, \
		SPRN_MCSRR0, SPRN_MCSRR1)

		/*
		@@ -293,12 +297,12 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)

		#define EXCEPTION(n, intno, label, hdlr, xfer) \
		START_EXCEPTION(label); \
		NORMAL_EXCEPTION_PROLOG(intno); \
		NORMAL_EXCEPTION_PROLOG(n, intno); \
		xfer(n, hdlr)

		#define CRITICAL_EXCEPTION(n, intno, label, hdlr) \
		START_EXCEPTION(label); \
		CRITICAL_EXCEPTION_PROLOG(intno); \
		CRITICAL_EXCEPTION_PROLOG(n, intno); \
		SAVE_MMU_REGS; \
		SAVE_xSRR(SRR); \
		EXC_XFER_TEMPLATE(hdlr, n+2, (MSR_KERNEL & ~(MSR_ME\|MSR_DE\|MSR_CE)), \
		@@ -306,7 +310,7 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)

		#define MCHECK_EXCEPTION(n, label, hdlr) \
		START_EXCEPTION(label); \
		MCHECK_EXCEPTION_PROLOG; \
		MCHECK_EXCEPTION_PROLOG(n); \
		mfspr r5,SPRN_ESR; \
		stw r5,_ESR(r11); \
		SAVE_xSRR(DSRR); \
		@@ -317,8 +321,6 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
		mcheck_transfer_to_handler, ret_from_mcheck_exc)

		#define EXC_XFER_TEMPLATE(hdlr, trap, msr, tfer, ret) \
		li r10,trap; \
		stw r10,_TRAP(r11); \
		bl tfer; \
		bl hdlr; \
		b ret; \
		@@ -346,7 +348,7 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
		*/
		#define DEBUG_DEBUG_EXCEPTION \
		START_EXCEPTION(DebugDebug); \
		DEBUG_EXCEPTION_PROLOG; \
		DEBUG_EXCEPTION_PROLOG(2000); \
		\
		/* \
		* If there is a single step or branch-taken exception in an \
		@@ -402,7 +404,7 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)

		#define DEBUG_CRIT_EXCEPTION \
		START_EXCEPTION(DebugCrit); \
		CRITICAL_EXCEPTION_PROLOG(DEBUG); \
		CRITICAL_EXCEPTION_PROLOG(2000,DEBUG); \
		\
		/* \
		* If there is a single step or branch-taken exception in an \
		@@ -457,7 +459,7 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)

		#define DATA_STORAGE_EXCEPTION \
		START_EXCEPTION(DataStorage) \
		NORMAL_EXCEPTION_PROLOG(DATA_STORAGE); \
		NORMAL_EXCEPTION_PROLOG(0x300, DATA_STORAGE); \
		mfspr r5,SPRN_ESR; /* Grab the ESR and save it */ \
		stw r5,_ESR(r11); \
		mfspr r4,SPRN_DEAR; /* Grab the DEAR */ \
		@@ -466,7 +468,7 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)

		#define INSTRUCTION_STORAGE_EXCEPTION \
		START_EXCEPTION(InstructionStorage) \
		NORMAL_EXCEPTION_PROLOG(INST_STORAGE); \
		NORMAL_EXCEPTION_PROLOG(0x400, INST_STORAGE); \
		mfspr r5,SPRN_ESR; /* Grab the ESR and save it */ \
		stw r5,_ESR(r11); \
		stw r12, _DEAR(r11); /* Pass SRR0 as arg2 */ \
		@@ -474,28 +476,28 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)

		#define ALIGNMENT_EXCEPTION \
		START_EXCEPTION(Alignment) \
		NORMAL_EXCEPTION_PROLOG(ALIGNMENT); \
		NORMAL_EXCEPTION_PROLOG(0x600, ALIGNMENT); \
		mfspr r4,SPRN_DEAR; /* Grab the DEAR and save it */ \
		stw r4,_DEAR(r11); \
		EXC_XFER_STD(0x0600, alignment_exception)

		#define PROGRAM_EXCEPTION \
		START_EXCEPTION(Program) \
		NORMAL_EXCEPTION_PROLOG(PROGRAM); \
		NORMAL_EXCEPTION_PROLOG(0x700, PROGRAM); \
		mfspr r4,SPRN_ESR; /* Grab the ESR and save it */ \
		stw r4,_ESR(r11); \
		EXC_XFER_STD(0x0700, program_check_exception)

		#define DECREMENTER_EXCEPTION \
		START_EXCEPTION(Decrementer) \
		NORMAL_EXCEPTION_PROLOG(DECREMENTER); \
		NORMAL_EXCEPTION_PROLOG(0x900, DECREMENTER); \
		lis r0,TSR_DIS@h; /* Setup the DEC interrupt mask */ \
		mtspr SPRN_TSR,r0; /* Clear the DEC interrupt */ \
		EXC_XFER_LITE(0x0900, timer_interrupt)

		#define FP_UNAVAILABLE_EXCEPTION \
		START_EXCEPTION(FloatingPointUnavailable) \
		NORMAL_EXCEPTION_PROLOG(FP_UNAVAIL); \
		NORMAL_EXCEPTION_PROLOG(0x800, FP_UNAVAIL); \
		beq 1f; \
		bl load_up_fpu; /* if from user, just load it up */ \
		b fast_exception_return; \