ARM kprobes: special hook for the kprobes breakpoint handler

[linux-2.6-omap-h63xx.git] / arch / arm / kernel / traps.c

diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index c34db4e868fa530c50b0e6baa7123c88eab76ec8..5595fdd75e8200ec0e8d5ea8a54c750ed0398e1f 100644 (file)
--- a/arch/arm/kernel/traps.c
+++ b/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>
@@ -46,15 +47,6 @@ __setup("user_debug=", user_debug_setup);
 
 static void dump_mem(const char *str, unsigned long bottom, unsigned long top);
 
-static inline int in_exception_text(unsigned long ptr)
-{
-       extern char __exception_text_start[];
-       extern char __exception_text_end[];
-
-       return ptr >= (unsigned long)&__exception_text_start &&
-              ptr < (unsigned long)&__exception_text_end;
-}
-
 void dump_backtrace_entry(unsigned long where, unsigned long from, unsigned long frame)
 {
 #ifdef CONFIG_KALLSYMS
@@ -322,6 +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 &&