--- zzzz-none-000/linux-3.10.107/arch/powerpc/include/asm/kprobes.h	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/powerpc/include/asm/kprobes.h	2021-02-04 17:41:59.000000000 +0000
@@ -30,6 +30,7 @@
 #include <linux/ptrace.h>
 #include <linux/percpu.h>
 #include <asm/probes.h>
+#include <asm/code-patching.h>
 
 #define  __ARCH_WANT_KPROBES_INSN_SLOT
 
@@ -40,34 +41,59 @@
 #define MAX_INSN_SIZE 1
 
 #ifdef CONFIG_PPC64
+#if defined(_CALL_ELF) && _CALL_ELF == 2
+/* PPC64 ABIv2 needs local entry point */
+#define kprobe_lookup_name(name, addr)					\
+{									\
+	addr = (kprobe_opcode_t *)kallsyms_lookup_name(name);		\
+	if (addr)							\
+		addr = (kprobe_opcode_t *)ppc_function_entry(addr);	\
+}
+#else
 /*
- * 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-existent symbol, kallsyms_lookup_name
- * 		  returns 0. Don't deref the NULL pointer in that case
+ * 64bit powerpc ABIv1 uses function descriptors:
+ * - Check for the dot variant of the symbol first.
+ * - If that fails, try looking up the symbol provided.
+ *
+ * This ensures we always get to the actual symbol and not the descriptor.
+ * Also handle <module:symbol> format.
  */
 #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;		\
-	} else {							\
-		char dot_name[KSYM_NAME_LEN];				\
+	char dot_name[MODULE_NAME_LEN + 1 + KSYM_NAME_LEN];		\
+	char *modsym;							\
+	bool dot_appended = false;					\
+	if ((modsym = strchr(name, ':')) != NULL) {			\
+		modsym++;						\
+		if (*modsym != '\0' && *modsym != '.') {		\
+			/* Convert to <module:.symbol> */		\
+			strncpy(dot_name, name, modsym - name);		\
+			dot_name[modsym - name] = '.';			\
+			dot_name[modsym - name + 1] = '\0';		\
+			strncat(dot_name, modsym,			\
+				sizeof(dot_name) - (modsym - name) - 2);\
+			dot_appended = true;				\
+		} else {						\
+			dot_name[0] = '\0';				\
+			strncat(dot_name, name, sizeof(dot_name) - 1);	\
+		}							\
+	} else if (name[0] != '.') {					\
 		dot_name[0] = '.';					\
 		dot_name[1] = '\0';					\
 		strncat(dot_name, name, KSYM_NAME_LEN - 2);		\
-		addr = (kprobe_opcode_t *)kallsyms_lookup_name(dot_name); \
+		dot_appended = true;					\
+	} else {							\
+		dot_name[0] = '\0';					\
+		strncat(dot_name, name, KSYM_NAME_LEN - 1);		\
+	}								\
+	addr = (kprobe_opcode_t *)kallsyms_lookup_name(dot_name);	\
+	if (!addr && dot_appended) {					\
+		/* Let's try the original non-dot symbol lookup	*/	\
+		addr = (kprobe_opcode_t *)kallsyms_lookup_name(name);	\
 	}								\
 }
-#endif
+#endif /* defined(_CALL_ELF) && _CALL_ELF == 2 */
+#endif /* CONFIG_PPC64 */
 
 #define flush_insn_slot(p)	do { } while (0)
 #define kretprobe_blacklist_size 0