diff --git a/arch/x86/kernel/kprobes_32.c b/arch/x86/kernel/kprobes_32.c
index e7d0d3c2ef6473faeb460e7e77e20e579eedeb23..06b86e5617f62c739bdc4b448985d46462078273 100644
--- a/arch/x86/kernel/kprobes_32.c
+++ b/arch/x86/kernel/kprobes_32.c
@@ -584,7 +584,7 @@ static int __kprobes post_kprobe_handler(struct pt_regs *regs)
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();
@@ -666,7 +666,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
ret = NOTIFY_STOP;
break;
case DIE_GPF:
- case DIE_PAGE_FAULT:
/* kprobe_running() needs smp_processor_id() */
preempt_disable();
if (kprobe_running() &&
diff --git a/arch/x86/kernel/kprobes_64.c b/arch/x86/kernel/kprobes_64.c
index 62e28e52d784c8da494ebb6d2e045f5d8a9cb2b6..7c16506d681fc56f985c65f2c4b22dea7a5019ea 100644
--- a/arch/x86/kernel/kprobes_64.c
+++ b/arch/x86/kernel/kprobes_64.c
@@ -657,7 +657,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
ret = NOTIFY_STOP;
break;
case DIE_GPF:
- case DIE_PAGE_FAULT:
/* kprobe_running() needs smp_processor_id() */
preempt_disable();
if (kprobe_running() &&
diff --git a/arch/x86/mm/fault_32.c b/arch/x86/mm/fault_32.c
index fcb38e7f35434113896abc3caad887c9aad665d1..be72c2a5b03b4a1e4fea65b3431faf21d1491d3a 100644
--- a/arch/x86/mm/fault_32.c
+++ b/arch/x86/mm/fault_32.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/desc.h>
@@ -32,33 +33,27 @@
extern void die(const char *,struct pt_regs *,long);
-static ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain);
-
-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_vm(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
/*
* Return EIP plus the CS segment base. The segment limit is also
@@ -331,7 +326,7 @@ fastcall void __kprobes do_page_fault(struct pt_regs *regs,
if (unlikely(address >= TASK_SIZE)) {
if (!(error_code & 0x0000000d) && 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
@@ -340,7 +335,7 @@ fastcall 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;
/* It's safe to allow irq's after cr2 has been saved and the vmalloc
diff --git a/arch/x86/mm/fault_64.c b/arch/x86/mm/fault_64.c
index 54816adb8e933c8c09e41afcf3008331afb5adc6..5e0e54906c488fe5b7266d013c072672a606ba29 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))
diff --git a/include/asm-avr32/kdebug.h b/include/asm-avr32/kdebug.h
index 7f54e2b15d136ab5e2ee2234ef49fd0700ab2473..fd7e99046b2f366be239078692c957381c223bc6 100644
--- a/include/asm-avr32/kdebug.h
+++ b/include/asm-avr32/kdebug.h
@@ -1,26 +1,10 @@
#ifndef __ASM_AVR32_KDEBUG_H
#define __ASM_AVR32_KDEBUG_H
-#include <linux/notifier.h>
-
/* Grossly misnamed. */
enum die_val {
DIE_BREAKPOINT,
DIE_SSTEP,
};
-/*
- * 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;
-}
-
#endif /* __ASM_AVR32_KDEBUG_H */
diff --git a/include/asm-avr32/kprobes.h b/include/asm-avr32/kprobes.h
index 190a6377c80969f7b5ef5313457b42fec539a99d..0f3e636e6e4dda8d36c89b50f697777f59bdf88d 100644
--- a/include/asm-avr32/kprobes.h
+++ b/include/asm-avr32/kprobes.h
@@ -17,8 +17,6 @@ typedef u16 kprobe_opcode_t;
#define BREAKPOINT_INSTRUCTION 0xd673 /* breakpoint */
#define MAX_INSN_SIZE 2
-#define ARCH_INACTIVE_KPROBE_COUNT 1
-
#define arch_remove_kprobe(p) do { } while (0)
/* Architecture specific copy of original instruction */
diff --git a/include/asm-ia64/kdebug.h b/include/asm-ia64/kdebug.h
index 320cd8e754ea44a9841e874251f2e7113721e84b..35e49407d06c6bdada5952abca95a9a45786c23d 100644
--- a/include/asm-ia64/kdebug.h
+++ b/include/asm-ia64/kdebug.h
@@ -26,21 +26,6 @@
* 2005-Oct Keith Owens <kaos@sgi.com>. Expand notify_die to cover more
* events.
*/
-#include <linux/notifier.h>
-
-/*
- * 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;
-}
enum die_val {
DIE_BREAK = 1,
diff --git a/include/asm-ia64/kprobes.h b/include/asm-ia64/kprobes.h
index 067d9dea68f9d627f41ba634e7169185bafcf5e4..6c79edf24d73adc1572b885417394bcb6c02ae13 100644
--- a/include/asm-ia64/kprobes.h
+++ b/include/asm-ia64/kprobes.h
@@ -83,7 +83,6 @@ struct kprobe_ctlblk {
};
#define ARCH_SUPPORTS_KRETPROBES
-#define ARCH_INACTIVE_KPROBE_COUNT 1
#define SLOT0_OPCODE_SHIFT (37)
#define SLOT1_p1_OPCODE_SHIFT (37 - (64-46))
diff --git a/include/asm-powerpc/kdebug.h b/include/asm-powerpc/kdebug.h
index 295f0162c60827a750664b9ece653d134f1a277f..ae6d206728afc476d015b15ee2a9f5e2588f467e 100644
--- a/include/asm-powerpc/kdebug.h
+++ b/include/asm-powerpc/kdebug.h
@@ -2,25 +2,6 @@
#define _ASM_POWERPC_KDEBUG_H
#ifdef __KERNEL__
-/* nearly identical to x86_64/i386 code */
-
-#include <linux/notifier.h>
-
-/*
- * 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 powerpc_die_chain;
-
/* Grossly misnamed. */
enum die_val {
DIE_OOPS = 1,
diff --git a/include/asm-powerpc/kprobes.h b/include/asm-powerpc/kprobes.h
index 8b08b447d6f31e2e300e39b3813dd090b7c2233f..c16973d5de6287dc4c14d1572065d747c719416e 100644
--- a/include/asm-powerpc/kprobes.h
+++ b/include/asm-powerpc/kprobes.h
@@ -81,7 +81,6 @@ typedef unsigned int kprobe_opcode_t;
#endif
#define ARCH_SUPPORTS_KRETPROBES
-#define ARCH_INACTIVE_KPROBE_COUNT 1
#define flush_insn_slot(p) do { } while (0)
void kretprobe_trampoline(void);
diff --git a/include/asm-s390/kdebug.h b/include/asm-s390/kdebug.h
index 04418af08f8511a6eea7c1d0ad09e04b49979e5e..40db27cd6e608df9c54285c6e1b52c6d572277f4 100644
--- a/include/asm-s390/kdebug.h
+++ b/include/asm-s390/kdebug.h
@@ -4,24 +4,9 @@
/*
* Feb 2006 Ported to s390 <grundym@us.ibm.com>
*/
-#include <linux/notifier.h>
struct pt_regs;
-/*
- * 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;
-}
-
enum die_val {
DIE_OOPS = 1,
DIE_BPT,
diff --git a/include/asm-s390/kprobes.h b/include/asm-s390/kprobes.h
index 340ba10446ea46d2aeca453903532bc537627610..8bc67cc9ffd2972a64f9da56564892e54d48d7c5 100644
--- a/include/asm-s390/kprobes.h
+++ b/include/asm-s390/kprobes.h
@@ -47,7 +47,6 @@ typedef u16 kprobe_opcode_t;
: (((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR)))
#define ARCH_SUPPORTS_KRETPROBES
-#define ARCH_INACTIVE_KPROBE_COUNT 0
#define KPROBE_SWAP_INST 0x10
diff --git a/include/asm-sh/kdebug.h b/include/asm-sh/kdebug.h
index 382cfc7deb732b233170b3e1ec69edb6d14abb17..49cd69051a8896392fa1c9335c1770c802d1aa15 100644
--- a/include/asm-sh/kdebug.h
+++ b/include/asm-sh/kdebug.h
@@ -1,8 +1,6 @@
#ifndef __ASM_SH_KDEBUG_H
#define __ASM_SH_KDEBUG_H
-#include <linux/notifier.h>
-
/* Grossly misnamed. */
enum die_val {
DIE_TRAP,
diff --git a/include/asm-sparc64/kdebug.h b/include/asm-sparc64/kdebug.h
index 9974c7b0aebc18563568cd50a5b5c2c457e5b908..f905b773235a2f977db3383559629d4fbd3e4fda 100644
--- a/include/asm-sparc64/kdebug.h
+++ b/include/asm-sparc64/kdebug.h
@@ -1,26 +1,8 @@
#ifndef _SPARC64_KDEBUG_H
#define _SPARC64_KDEBUG_H
-/* Nearly identical to x86_64/i386 code. */
-
-#include <linux/notifier.h>
-
struct pt_regs;
-/*
- * 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 void bad_trap(struct pt_regs *, long);
/* Grossly misnamed. */
diff --git a/include/asm-sparc64/kprobes.h b/include/asm-sparc64/kprobes.h
index 7f6774dca5f49f778c434c055ab7355e3711a4c4..a04145b77f9635e8a7a30504bef7f1b2cfdcc1e1 100644
--- a/include/asm-sparc64/kprobes.h
+++ b/include/asm-sparc64/kprobes.h
@@ -11,7 +11,6 @@ typedef u32 kprobe_opcode_t;
#define MAX_INSN_SIZE 2
#define arch_remove_kprobe(p) do {} while (0)
-#define ARCH_INACTIVE_KPROBE_COUNT 0
#define flush_insn_slot(p) \
do { flushi(&(p)->ainsn.insn[0]); \
diff --git a/include/asm-x86/kdebug_32.h b/include/asm-x86/kdebug_32.h
index a185b5f73e7ff466322cbaa8c8b9743925cce11d..181d437eef4bd059e320155d1a39dab15d15c649 100644
--- a/include/asm-x86/kdebug_32.h
+++ b/include/asm-x86/kdebug_32.h
@@ -5,14 +5,9 @@
* Aug-05 2004 Ported by Prasanna S Panchamukhi <prasanna@in.ibm.com>
* from x86_64 architecture.
*/
-#include <linux/notifier.h>
struct pt_regs;
-extern int register_page_fault_notifier(struct notifier_block *);
-extern int unregister_page_fault_notifier(struct notifier_block *);
-
-
/* Grossly misnamed. */
enum die_val {
DIE_OOPS = 1,
@@ -27,7 +22,6 @@ enum die_val {
DIE_GPF,
DIE_CALL,
DIE_NMI_IPI,
- DIE_PAGE_FAULT,
};
#endif
diff --git a/include/asm-x86/kdebug_64.h b/include/asm-x86/kdebug_64.h
index d7e2bcf49e4f0ee5ab826b8a2108c2f03f0d0b43..df413e05375e7f6b927c6128c38442d8c3474c56 100644
--- a/include/asm-x86/kdebug_64.h
+++ b/include/asm-x86/kdebug_64.h
@@ -1,13 +1,10 @@
#ifndef _X86_64_KDEBUG_H
#define _X86_64_KDEBUG_H 1
-#include <linux/notifier.h>
+#include <linux/compiler.h>
struct pt_regs;
-extern int register_page_fault_notifier(struct notifier_block *);
-extern int unregister_page_fault_notifier(struct notifier_block *);
-
/* Grossly misnamed. */
enum die_val {
DIE_OOPS = 1,
@@ -22,7 +19,6 @@ enum die_val {
DIE_GPF,
DIE_CALL,
DIE_NMI_IPI,
- DIE_PAGE_FAULT,
};
extern void printk_address(unsigned long address);
diff --git a/include/asm-x86/kprobes_32.h b/include/asm-x86/kprobes_32.h
index 06f7303c30ca15d111061cfcace36ec043b9362d..f2489d07ce88cdef0dec6d5d5d605a0d84a3c4f0 100644
--- a/include/asm-x86/kprobes_32.h
+++ b/include/asm-x86/kprobes_32.h
@@ -43,7 +43,6 @@ typedef u8 kprobe_opcode_t;
: (((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR)))
#define ARCH_SUPPORTS_KRETPROBES
-#define ARCH_INACTIVE_KPROBE_COUNT 0
#define flush_insn_slot(p) do { } while (0)
void arch_remove_kprobe(struct kprobe *p);
@@ -89,4 +88,5 @@ static inline void restore_interrupts(struct pt_regs *regs)
extern int kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data);
+extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
#endif /* _ASM_KPROBES_H */
diff --git a/include/asm-x86/kprobes_64.h b/include/asm-x86/kprobes_64.h
index 7db825403e013129655fab261035b1391944c888..3f495e5308b13499f4d7122e2bb90510bc293417 100644
--- a/include/asm-x86/kprobes_64.h
+++ b/include/asm-x86/kprobes_64.h
@@ -42,7 +42,6 @@ typedef u8 kprobe_opcode_t;
: (((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR)))
#define ARCH_SUPPORTS_KRETPROBES
-#define ARCH_INACTIVE_KPROBE_COUNT 1
void kretprobe_trampoline(void);
extern void arch_remove_kprobe(struct kprobe *p);
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 4b8a4493c541873a946e9d62161459fa4f94c35c..f9798ff7899f4a610823fd641fe5e2dde0e746f7 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -64,7 +64,6 @@
static struct hlist_head kprobe_table[KPROBE_TABLE_SIZE];
static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE];
-static atomic_t kprobe_count;
/* NOTE: change this value only with kprobe_mutex held */
static bool kprobe_enabled;
@@ -73,11 +72,6 @@ DEFINE_MUTEX(kprobe_mutex); /* Protects kprobe_table */
DEFINE_SPINLOCK(kretprobe_lock); /* Protects kretprobe_inst_table */
static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL;
-static struct notifier_block kprobe_page_fault_nb = {
- .notifier_call = kprobe_exceptions_notify,
- .priority = 0x7fffffff /* we need to notified first */
-};
-
#ifdef __ARCH_WANT_KPROBES_INSN_SLOT
/*
* kprobe->ainsn.insn points to the copy of the instruction to be
@@ -556,8 +550,6 @@ static int __kprobes __register_kprobe(struct kprobe *p,
old_p = get_kprobe(p->addr);
if (old_p) {
ret = register_aggr_kprobe(old_p, p);
- if (!ret)
- atomic_inc(&kprobe_count);
goto out;
}
@@ -569,13 +561,9 @@ static int __kprobes __register_kprobe(struct kprobe *p,
hlist_add_head_rcu(&p->hlist,
&kprobe_table[hash_ptr(p->addr, KPROBE_HASH_BITS)]);
- if (kprobe_enabled) {
- if (atomic_add_return(1, &kprobe_count) == \
- (ARCH_INACTIVE_KPROBE_COUNT + 1))
- register_page_fault_notifier(&kprobe_page_fault_nb);
-
+ if (kprobe_enabled)
arch_arm_kprobe(p);
- }
+
out:
mutex_unlock(&kprobe_mutex);
@@ -658,16 +646,6 @@ void __kprobes unregister_kprobe(struct kprobe *p)
}
mutex_unlock(&kprobe_mutex);
}
-
- /* Call unregister_page_fault_notifier()
- * if no probes are active
- */
- mutex_lock(&kprobe_mutex);
- if (atomic_add_return(-1, &kprobe_count) == \
- ARCH_INACTIVE_KPROBE_COUNT)
- unregister_page_fault_notifier(&kprobe_page_fault_nb);
- mutex_unlock(&kprobe_mutex);
- return;
}
static struct notifier_block kprobe_exceptions_nb = {
@@ -815,7 +793,6 @@ static int __init init_kprobes(void)
INIT_HLIST_HEAD(&kprobe_table[i]);
INIT_HLIST_HEAD(&kretprobe_inst_table[i]);
}
- atomic_set(&kprobe_count, 0);
/* By default, kprobes are enabled */
kprobe_enabled = true;
@@ -921,13 +898,6 @@ static void __kprobes enable_all_kprobes(void)
if (kprobe_enabled)
goto already_enabled;
- /*
- * Re-register the page fault notifier only if there are any
- * active probes at the time of enabling kprobes globally
- */
- if (atomic_read(&kprobe_count) > ARCH_INACTIVE_KPROBE_COUNT)
- register_page_fault_notifier(&kprobe_page_fault_nb);
-
for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
head = &kprobe_table[i];
hlist_for_each_entry_rcu(p, node, head, hlist)
@@ -968,10 +938,7 @@ static void __kprobes disable_all_kprobes(void)
mutex_unlock(&kprobe_mutex);
/* Allow all currently running kprobes to complete */
synchronize_sched();
-
- mutex_lock(&kprobe_mutex);
- /* Unconditionally unregister the page_fault notifier */
- unregister_page_fault_notifier(&kprobe_page_fault_nb);
+ return;
already_disabled:
mutex_unlock(&kprobe_mutex);