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Diffstat (limited to 'include/asm-powerpc/kprobes.h')
-rw-r--r--include/asm-powerpc/kprobes.h22
1 files changed, 22 insertions, 0 deletions
diff --git a/include/asm-powerpc/kprobes.h b/include/asm-powerpc/kprobes.h
index 34e1f89a5fa..2dafa376a63 100644
--- a/include/asm-powerpc/kprobes.h
+++ b/include/asm-powerpc/kprobes.h
@@ -44,6 +44,28 @@ typedef unsigned int kprobe_opcode_t;
#define IS_TDI(instr) (((instr) & 0xfc000000) == 0x08000000)
#define IS_TWI(instr) (((instr) & 0xfc000000) == 0x0c000000)
+/*
+ * 64bit powerpc uses function descriptors.
+ * Handle cases where:
+ * - 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 (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)
#define is_trap(instr) (IS_TW(instr) || IS_TD(instr) || \