diff --git a/arch/x86_64/mm/fault.c b/arch/x86_64/mm/fault.c index 55250593d8c9..0803d3858af1 100644 --- a/arch/x86_64/mm/fault.c +++ b/arch/x86_64/mm/fault.c @@ -41,6 +41,41 @@ #define PF_RSVD (1<<3) #define PF_INSTR (1<<4) +#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) +{ + vmalloc_sync_all(); + 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, const char *str, + struct pt_regs *regs, long err, int trap, int sig) +{ + struct die_args args = { + .regs = regs, + .str = str, + .err = err, + .trapnr = trap, + .signr = sig + }; + return atomic_notifier_call_chain(¬ify_page_fault_chain, val, &args); +} +#else +static inline int notify_page_fault(enum die_val val, const char *str, + struct pt_regs *regs, long err, int trap, int sig) +{ + return NOTIFY_DONE; +} +#endif + void bust_spinlocks(int yes) { int loglevel_save = console_loglevel; @@ -348,7 +383,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, if (vmalloc_fault(address) >= 0) return; } - if (notify_die(DIE_PAGE_FAULT, "page fault", regs, error_code, 14, + if (notify_page_fault(DIE_PAGE_FAULT, "page fault", regs, error_code, 14, SIGSEGV) == NOTIFY_STOP) return; /* @@ -358,7 +393,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, goto bad_area_nosemaphore; } - if (notify_die(DIE_PAGE_FAULT, "page fault", regs, error_code, 14, + if (notify_page_fault(DIE_PAGE_FAULT, "page fault", regs, error_code, 14, SIGSEGV) == NOTIFY_STOP) return; diff --git a/include/asm-x86_64/kdebug.h b/include/asm-x86_64/kdebug.h index cf795631d9b4..cd52c7f33bca 100644 --- a/include/asm-x86_64/kdebug.h +++ b/include/asm-x86_64/kdebug.h @@ -15,6 +15,8 @@ struct die_args { extern int register_die_notifier(struct notifier_block *); extern int unregister_die_notifier(struct notifier_block *); +extern int register_page_fault_notifier(struct notifier_block *); +extern int unregister_page_fault_notifier(struct notifier_block *); extern struct atomic_notifier_head die_chain; /* Grossly misnamed. */