Kprobes: print details of kretprobe on assertion failure
In certain cases like when the real return address can't be found or when
the number of tracked calls to a kretprobed function is less than the
number of returns, we may not be able to find the correct return address
after processing a kretprobe. Currently we just do a BUG_ON, but no
information is provided about the actual failing kretprobe.
Print out details of the kretprobe before calling BUG().
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index f264607..850ee87 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -157,6 +157,16 @@
struct task_struct *task;
};
+static inline void kretprobe_assert(struct kretprobe_instance *ri,
+ unsigned long orig_ret_address, unsigned long trampoline_address)
+{
+ if (!orig_ret_address || (orig_ret_address == trampoline_address)) {
+ printk("kretprobe BUG!: Processing kretprobe %p @ %p\n",
+ ri->rp, ri->rp->kp.addr);
+ BUG();
+ }
+}
+
extern spinlock_t kretprobe_lock;
extern struct mutex kprobe_mutex;
extern int arch_prepare_kprobe(struct kprobe *p);