[PATCH v5 04/21] powerpc: bad_page_fault, do_break get registers from regs
Christophe Leroy
christophe.leroy at csgroup.eu
Thu Jan 14 01:25:24 AEDT 2021
Le 13/01/2021 à 08:31, Nicholas Piggin a écrit :
> Similar to the previous patch this makes interrupt handler function
> types more regular so they can be wrapped with the next patch.
>
> bad_page_fault and do_break are not performance critical.
It's a bit different between do_break() and bad_page_fault():
- do_break() is not performance critical for sure
- bad_page_fault(), it doesn't matter, because bad_page_fault() was not using the address param so
it doesn't get anything from regs at the end.
Maybe it would be worth splitting in two patches, one for bad_page_fault() and one for do_break()
Christophe
>
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
> ---
> arch/powerpc/include/asm/bug.h | 4 ++--
> arch/powerpc/include/asm/debug.h | 3 +--
> arch/powerpc/kernel/entry_32.S | 3 +--
> arch/powerpc/kernel/exceptions-64e.S | 3 +--
> arch/powerpc/kernel/exceptions-64s.S | 3 +--
> arch/powerpc/kernel/head_8xx.S | 5 ++---
> arch/powerpc/kernel/process.c | 7 +++----
> arch/powerpc/kernel/traps.c | 2 +-
> arch/powerpc/mm/book3s64/hash_utils.c | 4 ++--
> arch/powerpc/mm/book3s64/slb.c | 2 +-
> arch/powerpc/mm/fault.c | 10 +++++-----
> arch/powerpc/platforms/8xx/machine_check.c | 2 +-
> 12 files changed, 21 insertions(+), 27 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/bug.h b/arch/powerpc/include/asm/bug.h
> index f7827e993196..4220789b9a97 100644
> --- a/arch/powerpc/include/asm/bug.h
> +++ b/arch/powerpc/include/asm/bug.h
> @@ -112,8 +112,8 @@
>
> struct pt_regs;
> long do_page_fault(struct pt_regs *);
> -extern void bad_page_fault(struct pt_regs *, unsigned long, int);
> -void __bad_page_fault(struct pt_regs *regs, unsigned long address, int sig);
> +void bad_page_fault(struct pt_regs *, int);
> +void __bad_page_fault(struct pt_regs *regs, int sig);
> extern void _exception(int, struct pt_regs *, int, unsigned long);
> extern void _exception_pkey(struct pt_regs *, unsigned long, int);
> extern void die(const char *, struct pt_regs *, long);
> diff --git a/arch/powerpc/include/asm/debug.h b/arch/powerpc/include/asm/debug.h
> index ec57daf87f40..0550eceab3ca 100644
> --- a/arch/powerpc/include/asm/debug.h
> +++ b/arch/powerpc/include/asm/debug.h
> @@ -52,8 +52,7 @@ extern void do_send_trap(struct pt_regs *regs, unsigned long address,
> unsigned long error_code, int brkpt);
> #else
>
> -extern void do_break(struct pt_regs *regs, unsigned long address,
> - unsigned long error_code);
> +void do_break(struct pt_regs *regs);
> #endif
>
> #endif /* _ASM_POWERPC_DEBUG_H */
> diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
> index a32157ce0551..a94127eed56b 100644
> --- a/arch/powerpc/kernel/entry_32.S
> +++ b/arch/powerpc/kernel/entry_32.S
> @@ -673,9 +673,8 @@ handle_page_fault:
> lwz r0,_TRAP(r1)
> clrrwi r0,r0,1
> stw r0,_TRAP(r1)
> - mr r5,r3
> + mr r4,r3 /* err arg for bad_page_fault */
> addi r3,r1,STACK_FRAME_OVERHEAD
> - lwz r4,_DAR(r1)
> bl __bad_page_fault
> b ret_from_except_full
>
> diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
> index 43e71d86dcbf..52421042a020 100644
> --- a/arch/powerpc/kernel/exceptions-64e.S
> +++ b/arch/powerpc/kernel/exceptions-64e.S
> @@ -1018,9 +1018,8 @@ storage_fault_common:
> bne- 1f
> b ret_from_except_lite
> 1: bl save_nvgprs
> - mr r5,r3
> + mr r4,r3
> addi r3,r1,STACK_FRAME_OVERHEAD
> - ld r4,_DAR(r1)
> bl __bad_page_fault
> b ret_from_except
>
> diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
> index 814cff2c649e..36dea2020ec5 100644
> --- a/arch/powerpc/kernel/exceptions-64s.S
> +++ b/arch/powerpc/kernel/exceptions-64s.S
> @@ -2136,8 +2136,7 @@ EXC_COMMON_BEGIN(h_data_storage_common)
> GEN_COMMON h_data_storage
> addi r3,r1,STACK_FRAME_OVERHEAD
> BEGIN_MMU_FTR_SECTION
> - ld r4,_DAR(r1)
> - li r5,SIGSEGV
> + li r4,SIGSEGV
> bl bad_page_fault
> MMU_FTR_SECTION_ELSE
> bl unknown_exception
> diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
> index 0b2c247cfdff..7869db974185 100644
> --- a/arch/powerpc/kernel/head_8xx.S
> +++ b/arch/powerpc/kernel/head_8xx.S
> @@ -364,10 +364,9 @@ do_databreakpoint:
> addi r3,r1,STACK_FRAME_OVERHEAD
> mfspr r4,SPRN_BAR
> stw r4,_DAR(r11)
> -#ifdef CONFIG_VMAP_STACK
> - lwz r5,_DSISR(r11)
> -#else
> +#ifndef CONFIG_VMAP_STACK
> mfspr r5,SPRN_DSISR
> + stw r5,_DSISR(r11)
> #endif
> EXC_XFER_STD(0x1c00, do_break)
>
> diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
> index a66f435dabbf..4f0f81e9420b 100644
> --- a/arch/powerpc/kernel/process.c
> +++ b/arch/powerpc/kernel/process.c
> @@ -659,11 +659,10 @@ static void do_break_handler(struct pt_regs *regs)
> }
> }
>
> -void do_break (struct pt_regs *regs, unsigned long address,
> - unsigned long error_code)
> +void do_break(struct pt_regs *regs)
> {
> current->thread.trap_nr = TRAP_HWBKPT;
> - if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code,
> + if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, regs->dsisr,
> 11, SIGSEGV) == NOTIFY_STOP)
> return;
>
> @@ -681,7 +680,7 @@ void do_break (struct pt_regs *regs, unsigned long address,
> do_break_handler(regs);
>
> /* Deliver the signal to userspace */
> - force_sig_fault(SIGTRAP, TRAP_HWBKPT, (void __user *)address);
> + force_sig_fault(SIGTRAP, TRAP_HWBKPT, (void __user *)regs->dar);
> }
> #endif /* CONFIG_PPC_ADV_DEBUG_REGS */
>
> diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
> index 3ec7b443fe6b..f3f6af3141ee 100644
> --- a/arch/powerpc/kernel/traps.c
> +++ b/arch/powerpc/kernel/traps.c
> @@ -1612,7 +1612,7 @@ void alignment_exception(struct pt_regs *regs)
> if (user_mode(regs))
> _exception(sig, regs, code, regs->dar);
> else
> - bad_page_fault(regs, regs->dar, sig);
> + bad_page_fault(regs, sig);
>
> bail:
> exception_exit(prev_state);
> diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c
> index 8d014924ee0d..77073a256cff 100644
> --- a/arch/powerpc/mm/book3s64/hash_utils.c
> +++ b/arch/powerpc/mm/book3s64/hash_utils.c
> @@ -1539,7 +1539,7 @@ long do_hash_fault(struct pt_regs *regs)
> * the access, or panic if there isn't a handler.
> */
> if (unlikely(in_nmi())) {
> - bad_page_fault(regs, ea, SIGSEGV);
> + bad_page_fault(regs, SIGSEGV);
> return 0;
> }
>
> @@ -1578,7 +1578,7 @@ long do_hash_fault(struct pt_regs *regs)
> else
> _exception(SIGBUS, regs, BUS_ADRERR, ea);
> } else {
> - bad_page_fault(regs, ea, SIGBUS);
> + bad_page_fault(regs, SIGBUS);
> }
> err = 0;
>
> diff --git a/arch/powerpc/mm/book3s64/slb.c b/arch/powerpc/mm/book3s64/slb.c
> index 985902ce0272..c581548b533f 100644
> --- a/arch/powerpc/mm/book3s64/slb.c
> +++ b/arch/powerpc/mm/book3s64/slb.c
> @@ -874,7 +874,7 @@ void do_bad_slb_fault(struct pt_regs *regs)
> if (user_mode(regs))
> _exception(SIGSEGV, regs, SEGV_BNDERR, regs->dar);
> else
> - bad_page_fault(regs, regs->dar, SIGSEGV);
> + bad_page_fault(regs, SIGSEGV);
> } else if (err == -EINVAL) {
> unrecoverable_exception(regs);
> } else {
> diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
> index e170501081a7..36604ff8b3ec 100644
> --- a/arch/powerpc/mm/fault.c
> +++ b/arch/powerpc/mm/fault.c
> @@ -569,14 +569,14 @@ long do_page_fault(struct pt_regs *regs)
> /* 32 and 64e handle these errors in asm */
> if (unlikely(err)) {
> if (err > 0) {
> - __bad_page_fault(regs, address, err);
> + __bad_page_fault(regs, err);
> err = 0;
> } else {
> /*
> * do_break() may change NV GPRS while handling the
> * breakpoint. Return -ve to caller to do that.
> */
> - do_break(regs, address, error_code);
> + do_break(regs);
> }
> }
> #endif
> @@ -592,7 +592,7 @@ NOKPROBE_SYMBOL(do_page_fault);
> * It is called from the DSI and ISI handlers in head.S and from some
> * of the procedures in traps.c.
> */
> -void __bad_page_fault(struct pt_regs *regs, unsigned long address, int sig)
> +void __bad_page_fault(struct pt_regs *regs, int sig)
> {
> int is_write = page_fault_is_write(regs->dsisr);
>
> @@ -630,7 +630,7 @@ void __bad_page_fault(struct pt_regs *regs, unsigned long address, int sig)
> die("Kernel access of bad area", regs, sig);
> }
>
> -void bad_page_fault(struct pt_regs *regs, unsigned long address, int sig)
> +void bad_page_fault(struct pt_regs *regs, int sig)
> {
> const struct exception_table_entry *entry;
>
> @@ -639,5 +639,5 @@ void bad_page_fault(struct pt_regs *regs, unsigned long address, int sig)
> if (entry)
> instruction_pointer_set(regs, extable_fixup(entry));
> else
> - __bad_page_fault(regs, address, sig);
> + __bad_page_fault(regs, sig);
> }
> diff --git a/arch/powerpc/platforms/8xx/machine_check.c b/arch/powerpc/platforms/8xx/machine_check.c
> index 88dedf38eccd..656365975895 100644
> --- a/arch/powerpc/platforms/8xx/machine_check.c
> +++ b/arch/powerpc/platforms/8xx/machine_check.c
> @@ -26,7 +26,7 @@ int machine_check_8xx(struct pt_regs *regs)
> * to deal with that than having a wart in the mcheck handler.
> * -- BenH
> */
> - bad_page_fault(regs, regs->dar, SIGBUS);
> + bad_page_fault(regs, SIGBUS);
> return 1;
> #else
> return 0;
>
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