diff options
Diffstat (limited to 'arch/x86/mm/fault_64.c')
| -rw-r--r-- | arch/x86/mm/fault_64.c | 44 |
1 files changed, 19 insertions, 25 deletions
diff --git a/arch/x86/mm/fault_64.c b/arch/x86/mm/fault_64.c index 54816adb8e9..5e0e54906c4 100644 --- a/arch/x86/mm/fault_64.c +++ b/arch/x86/mm/fault_64.c @@ -25,6 +25,7 @@ #include <linux/kprobes.h> #include <linux/uaccess.h> #include <linux/kdebug.h> +#include <linux/kprobes.h> #include <asm/system.h> #include <asm/pgalloc.h> @@ -40,34 +41,27 @@ #define PF_RSVD (1<<3) #define PF_INSTR (1<<4) -static ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain); - -/* Hook to register for page fault notifications */ -int register_page_fault_notifier(struct notifier_block *nb) +#ifdef CONFIG_KPROBES +static inline int notify_page_fault(struct pt_regs *regs) { - vmalloc_sync_all(); - return atomic_notifier_chain_register(¬ify_page_fault_chain, nb); -} -EXPORT_SYMBOL_GPL(register_page_fault_notifier); + int ret = 0; + + /* kprobe_running() needs smp_processor_id() */ + if (!user_mode(regs)) { + preempt_disable(); + if (kprobe_running() && kprobe_fault_handler(regs, 14)) + ret = 1; + preempt_enable(); + } -int unregister_page_fault_notifier(struct notifier_block *nb) -{ - return atomic_notifier_chain_unregister(¬ify_page_fault_chain, nb); + return ret; } -EXPORT_SYMBOL_GPL(unregister_page_fault_notifier); - -static inline int notify_page_fault(struct pt_regs *regs, long err) +#else +static inline int notify_page_fault(struct pt_regs *regs) { - struct die_args args = { - .regs = regs, - .str = "page fault", - .err = err, - .trapnr = 14, - .signr = SIGSEGV - }; - return atomic_notifier_call_chain(¬ify_page_fault_chain, - DIE_PAGE_FAULT, &args); + return 0; } +#endif /* Sometimes the CPU reports invalid exceptions on prefetch. Check that here and ignore. @@ -345,7 +339,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, if (vmalloc_fault(address) >= 0) return; } - if (notify_page_fault(regs, error_code) == NOTIFY_STOP) + if (notify_page_fault(regs)) return; /* * Don't take the mm semaphore here. If we fixup a prefetch @@ -354,7 +348,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, goto bad_area_nosemaphore; } - if (notify_page_fault(regs, error_code) == NOTIFY_STOP) + if (notify_page_fault(regs)) return; if (likely(regs->eflags & X86_EFLAGS_IF)) |