---

yaml --- r: 77452 b: refs/heads/master c: 7969691 h: refs/heads/master v: v3
git-mirror · Jan 26, 2008 · 47fdb42 · 47fdb42
1 parent 7ccbd30
commit 47fdb42
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Showing 4 changed files with 21 additions and 8 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 785d3cd286f0bf67d1bf692559b9ae5de12678f5
+refs/heads/master: 796969104cab0d454dbc792ad0d12a4f365a8564
diff --git a/trunk/arch/arm/kernel/kprobes.c b/trunk/arch/arm/kernel/kprobes.c
@@ -26,12 +26,6 @@
 #include <asm/traps.h>
 #include <asm/cacheflush.h>
 
-/*
- * This undefined instruction must be unique and
- * reserved solely for kprobes' use.
- */
-#define KPROBE_BREAKPOINT_INSTRUCTION	0xe7f001f8
-
 #define MIN_STACK_SIZE(addr) 				\
 	min((unsigned long)MAX_STACK_SIZE,		\
 	    (unsigned long)current_thread_info() + THREAD_START_SP - (addr))
@@ -206,7 +200,7 @@ void __kprobes kprobe_handler(struct pt_regs *regs)
 	}
 }
 
-static int kprobe_trap_handler(struct pt_regs *regs, unsigned int instr)
+int kprobe_trap_handler(struct pt_regs *regs, unsigned int instr)
 {
 	kprobe_handler(regs);
 	return 0;

diff --git a/trunk/arch/arm/kernel/traps.c b/trunk/arch/arm/kernel/traps.c
@@ -19,6 +19,7 @@
 #include <linux/kallsyms.h>
 #include <linux/delay.h>
 #include <linux/init.h>
+#include <linux/kprobes.h>
 
 #include <asm/atomic.h>
 #include <asm/cacheflush.h>
@@ -313,6 +314,17 @@ asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
 		get_user(instr, (u32 __user *)pc);
 	}
 
+#ifdef CONFIG_KPROBES
+	/*
+	 * It is possible to have recursive kprobes, so we can't call
+	 * the kprobe trap handler with the undef_lock held.
+	 */
+	if (instr == KPROBE_BREAKPOINT_INSTRUCTION && !user_mode(regs)) {
+		kprobe_trap_handler(regs, instr);
+		return;
+	}
+#endif
+
 	spin_lock_irqsave(&undef_lock, flags);
 	list_for_each_entry(hook, &undef_hook, node) {
 		if ((instr & hook->instr_mask) == hook->instr_val &&

diff --git a/trunk/include/asm-arm/kprobes.h b/trunk/include/asm-arm/kprobes.h
@@ -25,6 +25,12 @@
 #define MAX_INSN_SIZE			2
 #define MAX_STACK_SIZE			64	/* 32 would probably be OK */
 
+/*
+ * This undefined instruction must be unique and
+ * reserved solely for kprobes' use.
+ */
+#define KPROBE_BREAKPOINT_INSTRUCTION	0xe7f001f8
+
 #define regs_return_value(regs)		((regs)->ARM_r0)
 #define flush_insn_slot(p)		do { } while (0)
 #define kretprobe_blacklist_size	0
@@ -55,6 +61,7 @@ struct kprobe_ctlblk {
 
 void arch_remove_kprobe(struct kprobe *);
 
+int kprobe_trap_handler(struct pt_regs *regs, unsigned int instr);
 int kprobe_fault_handler(struct pt_regs *regs, unsigned int fsr);
 int kprobe_exceptions_notify(struct notifier_block *self,
 			     unsigned long val, void *data);