X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=arch%2Fx86_64%2Fkernel%2Fkprobes.c;h=14f0ced613b683706f6d360c8ef835b2b9243d08;hb=debf798b1ed82053689d900670eb27fb2f1b4bd3;hp=dddeb678b440df5782af858f8db64100082c6f8a;hpb=89de09a9ba9ce293228b1f1aa3c68b5af33a70ce;p=powerpc.git

diff --git a/arch/x86_64/kernel/kprobes.c b/arch/x86_64/kernel/kprobes.c
index dddeb678b4..14f0ced613 100644
--- a/arch/x86_64/kernel/kprobes.c
+++ b/arch/x86_64/kernel/kprobes.c
@@ -42,8 +42,8 @@
 #include <asm/pgtable.h>
 #include <asm/kdebug.h>
 
-static DECLARE_MUTEX(kprobe_mutex);
 void jprobe_return_end(void);
+static void __kprobes arch_copy_kprobe(struct kprobe *p);
 
 DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
@@ -69,12 +69,11 @@ static inline int is_IF_modifier(kprobe_opcode_t *insn)
 int __kprobes arch_prepare_kprobe(struct kprobe *p)
 {
 	/* insn: must be on special executable page on x86_64. */
-	down(&kprobe_mutex);
 	p->ainsn.insn = get_insn_slot();
-	up(&kprobe_mutex);
 	if (!p->ainsn.insn) {
 		return -ENOMEM;
 	}
+	arch_copy_kprobe(p);
 	return 0;
 }
 
@@ -181,7 +180,7 @@ static inline s32 *is_riprel(u8 *insn)
 	return NULL;
 }
 
-void __kprobes arch_copy_kprobe(struct kprobe *p)
+static void __kprobes arch_copy_kprobe(struct kprobe *p)
 {
 	s32 *ripdisp;
 	memcpy(p->ainsn.insn, p->addr, MAX_INSN_SIZE);
@@ -223,9 +222,9 @@ void __kprobes arch_disarm_kprobe(struct kprobe *p)
 
 void __kprobes arch_remove_kprobe(struct kprobe *p)
 {
-	down(&kprobe_mutex);
+	mutex_lock(&kprobe_mutex);
 	free_insn_slot(p->ainsn.insn);
-	up(&kprobe_mutex);
+	mutex_unlock(&kprobe_mutex);
 }
 
 static inline void save_previous_kprobe(struct kprobe_ctlblk *kcb)
@@ -329,12 +328,21 @@ int __kprobes kprobe_handler(struct pt_regs *regs)
 				 */
 				save_previous_kprobe(kcb);
 				set_current_kprobe(p, regs, kcb);
-				p->nmissed++;
+				kprobes_inc_nmissed_count(p);
 				prepare_singlestep(p, regs);
 				kcb->kprobe_status = KPROBE_REENTER;
 				return 1;
 			}
 		} else {
+			if (*addr != BREAKPOINT_INSTRUCTION) {
+			/* The breakpoint instruction was removed by
+			 * another cpu right after we hit, no further
+			 * handling of this interrupt is appropriate
+			 */
+				regs->rip = (unsigned long)addr;
+				ret = 1;
+				goto no_kprobe;
+			}
 			p = __get_cpu_var(current_kprobe);
 			if (p->break_handler && p->break_handler(p, regs)) {
 				goto ss_probe;