[PATCH] kprobes: handle symbol resolution when <module:.symbol> is specified

kallsyms_lookup_name() allows for <module:symbol> style specification for
looking up symbol addresses.  Handle the case where the user specifies
<module:.symbol> on powerpc, given that 64-bit powerpc uses function
descriptors.

Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 11 insertions, 4 deletions

diff --git a/include/asm-powerpc/kprobes.h b/include/asm-powerpc/kprobes.h
index 1ef54be6abfa..2dafa376a63f 100644
--- a/include/asm-powerpc/kprobes.h
+++ b/include/asm-powerpc/kprobes.h
@@ -47,16 +47,23 @@ typedef unsigned int kprobe_opcode_t;
 /*
  * 64bit powerpc uses function descriptors.
  * Handle cases where:
- *              - User passes a <.symbol>
- *              - User passes a <symbol>
+ *              - User passes a <.symbol> or <module:.symbol>
+ *              - User passes a <symbol> or <module:symbol>
  *              - User passes a non-existant symbol, kallsyms_lookup_name
  *                returns 0. Don't deref the NULL pointer in that case
  */
 #define kprobe_lookup_name(name, addr)                                  \
 {                                                                       \
         addr = (kprobe_opcode_t *)kallsyms_lookup_name(name);           \
-        if (!(name[0] == '.') && addr)                                  \
-                addr = *(kprobe_opcode_t **)addr;                       \
+        if (addr) {                                                     \
+                char *colon;                                            \
+                if ((colon = strchr(name, ':')) != NULL) {              \
+                        colon++;                                        \
+                        if (*colon != '\0' && *colon != '.')            \
+                                addr = *(kprobe_opcode_t **)addr;       \
+                } else if (name[0] != '.')                              \
+                        addr = *(kprobe_opcode_t **)addr;               \
+        }                                                               \
 }
 
 #define JPROBE_ENTRY(pentry)    (kprobe_opcode_t *)((func_descr_t *)pentry)