diff options
Diffstat (limited to 'arch/powerpc/include/asm/kprobes.h')
| -rw-r--r-- | arch/powerpc/include/asm/kprobes.h | 63 |
1 files changed, 44 insertions, 19 deletions
diff --git a/arch/powerpc/include/asm/kprobes.h b/arch/powerpc/include/asm/kprobes.h index af15d4d8d604..039b583db029 100644 --- a/arch/powerpc/include/asm/kprobes.h +++ b/arch/powerpc/include/asm/kprobes.h @@ -41,34 +41,59 @@ typedef ppc_opcode_t kprobe_opcode_t; #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 *)ppc_function_entry(addr); \ - } else if (name[0] != '.') \ - addr = (kprobe_opcode_t *)ppc_function_entry(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 |