Re: [PATCH v3 03/19] powerpc: bad_page_fault, do_break get registers from regs
From: Christophe Leroy <hidden>
Date: 2020-12-22 14:44:41
Le 28/11/2020 à 15:40, 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.
I partly took your changes into one of my series, in different order though. Please have a look at https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=221656 patches 4 to 7 I think some of the changes are missing in your series, especially the changes in entry_32.S from patch 7. Will see how our two series make their way into mainline, yours needs rebase anyway. Christophe
quoted hunk ↗ jump to hunk
[32s DABR code from Christophe Leroy [off-list ref]] Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- arch/powerpc/include/asm/bug.h | 2 +- arch/powerpc/include/asm/debug.h | 3 +-- arch/powerpc/kernel/entry_32.S | 18 +----------------- arch/powerpc/kernel/exceptions-64e.S | 3 +-- arch/powerpc/kernel/exceptions-64s.S | 3 +-- arch/powerpc/kernel/head_8xx.S | 5 ++--- arch/powerpc/kernel/head_book3s_32.S | 3 +++ 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 +- 13 files changed, 23 insertions(+), 41 deletions(-)diff --git a/arch/powerpc/include/asm/bug.h b/arch/powerpc/include/asm/bug.h index 897bad6b6bbb..49162faba33f 100644 --- a/arch/powerpc/include/asm/bug.h +++ b/arch/powerpc/include/asm/bug.h@@ -113,7 +113,7 @@ struct pt_regs; long do_page_fault(struct pt_regs *); long hash__do_page_fault(struct pt_regs *); -extern void bad_page_fault(struct pt_regs *, unsigned long, int); +void bad_page_fault(struct pt_regs *, int); 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 8cdc8bcde703..57b8e95ea2a0 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S@@ -657,10 +657,6 @@ ppc_swapcontext: .globl handle_page_fault handle_page_fault: addi r3,r1,STACK_FRAME_OVERHEAD -#ifdef CONFIG_PPC_BOOK3S_32 - andis. r0,r5,DSISR_DABRMATCH@h - bne- handle_dabr_fault -#endif bl do_page_fault cmpwi r3,0 beq+ ret_from_except@@ -668,23 +664,11 @@ 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 -#ifdef CONFIG_PPC_BOOK3S_32 - /* We have a data breakpoint exception - handle it */ -handle_dabr_fault: - SAVE_NVGPRS(r1) - lwz r0,_TRAP(r1) - clrrwi r0,r0,1 - stw r0,_TRAP(r1) - bl do_break - b ret_from_except_full -#endif - /* * This routine switches between two different tasks. The process * state of one is saved on its kernel stack. Then the statediff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S index 25fa7d5a643c..dc728bb1c89a 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_exceptdiff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 690058043b17..77b730f515c4 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_exceptiondiff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index 8acd365a2be6..71ad7ce28469 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S@@ -376,10 +376,9 @@ 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/head_book3s_32.S b/arch/powerpc/kernel/head_book3s_32.S index 7addf67832f9..5875f8795d5b 100644 --- a/arch/powerpc/kernel/head_book3s_32.S +++ b/arch/powerpc/kernel/head_book3s_32.S@@ -689,7 +689,10 @@ handle_page_fault_tramp_1: #endif /* fall through */ handle_page_fault_tramp_2: + andis. r0, r5, DSISR_DABRMATCH@h + bne- 1f EXC_XFER_LITE(0x300, handle_page_fault) +1: EXC_XFER_STD(0x300, do_break) #ifdef CONFIG_VMAP_STACK .macro save_regs_thread threaddiff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index d421a2c7f822..0bdd3ed653df 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c@@ -660,11 +660,10 @@ 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;@@ -682,7 +681,7 @@ 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 5006dcbe1d9f..902fcbd1a778 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c@@ -1641,7 +1641,7 @@ 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 0f0bd4af4b2d..731518e7d56f 100644 --- a/arch/powerpc/mm/book3s64/hash_utils.c +++ b/arch/powerpc/mm/book3s64/hash_utils.c@@ -1537,7 +1537,7 @@ 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; }@@ -1576,7 +1576,7 @@ 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 cc34d50874c1..ae89ad516247 100644 --- a/arch/powerpc/mm/book3s64/slb.c +++ b/arch/powerpc/mm/book3s64/slb.c@@ -898,7 +898,7 @@ 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 390a296b16a3..e11989be8f1c 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c@@ -562,14 +562,14 @@ long do_page_fault(struct pt_regs *regs) /* 32 and 64e handle errors in their asm code */ 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@@ -591,14 +591,14 @@ long hash__do_page_fault(struct pt_regs *regs) err = __do_page_fault(regs, address, error_code); 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); } }@@ -612,7 +612,7 @@ NOKPROBE_SYMBOL(hash__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) { const struct exception_table_entry *entry; int is_write = page_fault_is_write(regs->dsisr);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;