From 3a2e117e220f000f95187ea1e1bbe83b0ed5fdfb Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Tue, 1 May 2007 16:33:10 +0900 Subject: [PATCH] sh: Add die chain notifiers. Add the atomic die chains in, kprobes needs these. Signed-off-by: Paul Mundt --- arch/sh/kernel/process.c | 15 ++++++++++++--- arch/sh/kernel/traps.c | 19 +++++++++++++++++-- arch/sh/mm/fault.c | 39 +++++++++++++++++++++++++++++++++++++-- include/asm-sh/kdebug.h | 35 +++++++++++++++++++++++++++++++++++ include/asm-sh/system.h | 3 +++ 5 files changed, 104 insertions(+), 7 deletions(-) create mode 100644 include/asm-sh/kdebug.h diff --git a/arch/sh/kernel/process.c b/arch/sh/kernel/process.c index 286c80388b..329b3f3051 100644 --- a/arch/sh/kernel/process.c +++ b/arch/sh/kernel/process.c @@ -7,7 +7,7 @@ * * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima * Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC - * Copyright (C) 2002 - 2006 Paul Mundt + * Copyright (C) 2002 - 2007 Paul Mundt */ #include #include @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -299,8 +300,8 @@ static void ubc_set_tracing(int asid, unsigned long pc) ctrl_outl(0, UBC_BAMRA); if (current_cpu_data.type == CPU_SH7729 || - current_cpu_data.type == CPU_SH7710 || - current_cpu_data.type == CPU_SH7712 ) { + current_cpu_data.type == CPU_SH7710 || + current_cpu_data.type == CPU_SH7712) { ctrl_outw(BBR_INST | BBR_READ | BBR_CPU, UBC_BBRA); ctrl_outl(BRCR_PCBA | BRCR_PCTE, UBC_BRCR); } else { @@ -496,6 +497,10 @@ asmlinkage void debug_trap_handler(unsigned long r4, unsigned long r5, /* Rewind */ regs->pc -= 2; + if (notify_die(DIE_TRAP, regs, regs->tra & 0xff, + SIGTRAP) == NOTIFY_STOP) + return; + force_sig(SIGTRAP, current); } @@ -511,6 +516,10 @@ asmlinkage void bug_trap_handler(unsigned long r4, unsigned long r5, /* Rewind */ regs->pc -= 2; + if (notify_die(DIE_TRAP, regs, TRAPA_BUG_OPCODE & 0xff, + SIGTRAP) == NOTIFY_STOP) + return; + #ifdef CONFIG_BUG if (__kernel_text_address(instruction_pointer(regs))) { u16 insn = *(u16 *)instruction_pointer(regs); diff --git a/arch/sh/kernel/traps.c b/arch/sh/kernel/traps.c index 7710783827..7b40f0ff3d 100644 --- a/arch/sh/kernel/traps.c +++ b/arch/sh/kernel/traps.c @@ -5,7 +5,7 @@ * SuperH version: Copyright (C) 1999 Niibe Yutaka * Copyright (C) 2000 Philipp Rumpf * Copyright (C) 2000 David Howells - * Copyright (C) 2002 - 2006 Paul Mundt + * Copyright (C) 2002 - 2007 Paul Mundt * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive @@ -23,6 +23,7 @@ #include #include #include +#include #ifdef CONFIG_SH_KGDB #include @@ -75,7 +76,21 @@ static void dump_mem(const char *str, unsigned long bottom, unsigned long top) } } -DEFINE_SPINLOCK(die_lock); +ATOMIC_NOTIFIER_HEAD(shdie_chain); + +int register_die_notifier(struct notifier_block *nb) +{ + return atomic_notifier_chain_register(&shdie_chain, nb); +} +EXPORT_SYMBOL(register_die_notifier); + +int unregister_die_notifier(struct notifier_block *nb) +{ + return atomic_notifier_chain_unregister(&shdie_chain, nb); +} +EXPORT_SYMBOL(unregister_die_notifier); + +static DEFINE_SPINLOCK(die_lock); void die(const char * str, struct pt_regs * regs, long err) { diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c index fa5d7f0b9f..0ecc117cad 100644 --- a/arch/sh/mm/fault.c +++ b/arch/sh/mm/fault.c @@ -2,7 +2,7 @@ * Page fault handler for SH with an MMU. * * Copyright (C) 1999 Niibe Yutaka - * Copyright (C) 2003 Paul Mundt + * Copyright (C) 2003 - 2007 Paul Mundt * * Based on linux/arch/i386/mm/fault.c: * Copyright (C) 1995 Linus Torvalds @@ -15,12 +15,42 @@ #include #include #include +#include #include #include #include #include -extern void die(const char *,struct pt_regs *,long); +#ifdef CONFIG_KPROBES +ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain); + +/* Hook to register for page fault notifications */ +int register_page_fault_notifier(struct notifier_block *nb) +{ + return atomic_notifier_chain_register(¬ify_page_fault_chain, nb); +} + +int unregister_page_fault_notifier(struct notifier_block *nb) +{ + return atomic_notifier_chain_unregister(¬ify_page_fault_chain, nb); +} + +static inline int notify_page_fault(enum die_val val, struct pt_regs *regs, + int trap, int sig) +{ + struct die_args args = { + .regs = regs, + .trapnr = trap, + }; + return atomic_notifier_call_chain(¬ify_page_fault_chain, val, &args); +} +#else +static inline int notify_page_fault(enum die_val val, struct pt_regs *regs, + int trap, int sig) +{ + return NOTIFY_DONE; +} +#endif /* * This routine handles page faults. It determines the address, @@ -39,6 +69,11 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, siginfo_t info; trace_hardirqs_on(); + + if (notify_page_fault(DIE_PAGE_FAULT, regs, + writeaccess, SIGSEGV) == NOTIFY_STOP) + return; + local_irq_enable(); #ifdef CONFIG_SH_KGDB diff --git a/include/asm-sh/kdebug.h b/include/asm-sh/kdebug.h new file mode 100644 index 0000000000..ef009baf5a --- /dev/null +++ b/include/asm-sh/kdebug.h @@ -0,0 +1,35 @@ +#ifndef __ASM_SH_KDEBUG_H +#define __ASM_SH_KDEBUG_H + +#include + +struct pt_regs; + +struct die_args { + struct pt_regs *regs; + int trapnr; +}; + +int register_die_notifier(struct notifier_block *nb); +int unregister_die_notifier(struct notifier_block *nb); +int register_page_fault_notifier(struct notifier_block *nb); +int unregister_page_fault_notifier(struct notifier_block *nb); +extern struct atomic_notifier_head shdie_chain; + +/* Grossly misnamed. */ +enum die_val { + DIE_TRAP, + DIE_PAGE_FAULT, +}; + +static inline int notify_die(enum die_val val, struct pt_regs *regs, + int trap, int sig) +{ + struct die_args args = { + .regs = regs, + .trapnr = trap, + }; + + return atomic_notifier_call_chain(&shdie_chain, val, &args); +} +#endif /* __ASM_SH_KDEBUG_H */ diff --git a/include/asm-sh/system.h b/include/asm-sh/system.h index 4a6a19f4f8..127af30486 100644 --- a/include/asm-sh/system.h +++ b/include/asm-sh/system.h @@ -9,6 +9,7 @@ #include #include #include +#include /* * switch_to() should switch tasks to task nr n, first @@ -255,6 +256,8 @@ static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old, (unsigned long)_n_, sizeof(*(ptr))); \ }) +extern void die(const char *str, struct pt_regs *regs, long err) __attribute__ ((noreturn)); + extern void *set_exception_table_vec(unsigned int vec, void *handler); static inline void *set_exception_table_evt(unsigned int evt, void *handler) -- 2.39.5