summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--arch/s390/kernel/kprobes.c3
-rw-r--r--arch/s390/mm/fault.c40
-rw-r--r--include/asm-s390/kdebug.h18
-rw-r--r--include/asm-s390/kprobes.h16
4 files changed, 33 insertions, 44 deletions
diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c
index 993f353..23c61f6 100644
--- a/arch/s390/kernel/kprobes.c
+++ b/arch/s390/kernel/kprobes.c
@@ -516,7 +516,7 @@ out:
return 1;
}
-static int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
+int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
{
struct kprobe *cur = kprobe_running();
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
@@ -603,7 +603,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
ret = NOTIFY_STOP;
break;
case DIE_TRAP:
- case DIE_PAGE_FAULT:
/* kprobe_running() needs smp_processor_id() */
preempt_disable();
if (kprobe_running() &&
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 2b76a87..91f705a 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -52,38 +52,24 @@ extern int sysctl_userprocess_debug;
extern void die(const char *,struct pt_regs *,long);
#ifdef CONFIG_KPROBES
-static ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain);
-int register_page_fault_notifier(struct notifier_block *nb)
-{
- return atomic_notifier_chain_register(&notify_page_fault_chain, nb);
-}
-
-int unregister_page_fault_notifier(struct notifier_block *nb)
-{
- return atomic_notifier_chain_unregister(&notify_page_fault_chain, nb);
-}
-
-static int __kprobes __notify_page_fault(struct pt_regs *regs, long err)
-{
- struct die_args args = { .str = "page fault",
- .trapnr = 14,
- .signr = SIGSEGV };
- args.regs = regs;
- args.err = err;
- return atomic_notifier_call_chain(&notify_page_fault_chain,
- DIE_PAGE_FAULT, &args);
-}
-
static inline int notify_page_fault(struct pt_regs *regs, long err)
{
- if (unlikely(kprobe_running()))
- return __notify_page_fault(regs, err);
- return NOTIFY_DONE;
+ 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();
+ }
+
+ return ret;
}
#else
static inline int notify_page_fault(struct pt_regs *regs, long err)
{
- return NOTIFY_DONE;
+ return 0;
}
#endif
@@ -319,7 +305,7 @@ do_exception(struct pt_regs *regs, unsigned long error_code, int write)
int space;
int si_code;
- if (notify_page_fault(regs, error_code) == NOTIFY_STOP)
+ if (notify_page_fault(regs, error_code))
return;
tsk = current;
diff --git a/include/asm-s390/kdebug.h b/include/asm-s390/kdebug.h
index 1b50f89..d2d7ad27 100644
--- a/include/asm-s390/kdebug.h
+++ b/include/asm-s390/kdebug.h
@@ -22,8 +22,21 @@ 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 *);
+
+/*
+ * These are only here because kprobes.c wants them to implement a
+ * blatant layering violation. Will hopefully go away soon once all
+ * architectures are updated.
+ */
+static inline int register_page_fault_notifier(struct notifier_block *nb)
+{
+ return 0;
+}
+static inline int unregister_page_fault_notifier(struct notifier_block *nb)
+{
+ return 0;
+}
+
extern struct atomic_notifier_head s390die_chain;
enum die_val {
@@ -39,7 +52,6 @@ enum die_val {
DIE_GPF,
DIE_CALL,
DIE_NMI_IPI,
- DIE_PAGE_FAULT,
};
static inline int notify_die(enum die_val val, const char *str,
diff --git a/include/asm-s390/kprobes.h b/include/asm-s390/kprobes.h
index b847ff0..830fe4c 100644
--- a/include/asm-s390/kprobes.h
+++ b/include/asm-s390/kprobes.h
@@ -97,18 +97,10 @@ void kretprobe_trampoline(void);
int is_prohibited_opcode(kprobe_opcode_t *instruction);
void get_instruction_type(struct arch_specific_insn *ainsn);
+int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
+int kprobe_exceptions_notify(struct notifier_block *self,
+ unsigned long val, void *data);
+
#define flush_insn_slot(p) do { } while (0)
#endif /* _ASM_S390_KPROBES_H */
-
-#ifdef CONFIG_KPROBES
-
-extern int kprobe_exceptions_notify(struct notifier_block *self,
- unsigned long val, void *data);
-#else /* !CONFIG_KPROBES */
-static inline int kprobe_exceptions_notify(struct notifier_block *self,
- unsigned long val, void *data)
-{
- return 0;
-}
-#endif
OpenPOWER on IntegriCloud