diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 6aa6fb6f7bd9..f954c26de231 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -825,7 +825,6 @@ static size_t syscall_arg__scnprintf_signum(char *bf, size_t size, struct syscal
 	P_SIGNUM(PIPE);
 	P_SIGNUM(ALRM);
 	P_SIGNUM(TERM);
-	P_SIGNUM(STKFLT);
 	P_SIGNUM(CHLD);
 	P_SIGNUM(CONT);
 	P_SIGNUM(STOP);
@@ -841,6 +840,15 @@ static size_t syscall_arg__scnprintf_signum(char *bf, size_t size, struct syscal
 	P_SIGNUM(IO);
 	P_SIGNUM(PWR);
 	P_SIGNUM(SYS);
+#ifdef SIGEMT
+	P_SIGNUM(EMT);
+#endif
+#ifdef SIGSTKFLT
+	P_SIGNUM(STKFLT);
+#endif
+#ifdef SIGSWI
+	P_SIGNUM(SWI);
+#endif
 	default: break;
 	}
 
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index c872991e0f65..620a1983b76b 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -1213,7 +1213,7 @@ static void ip__resolve_ams(struct machine *machine, struct thread *thread,
 		 */
 		thread__find_addr_location(thread, machine, m, MAP__FUNCTION,
 				ip, &al);
-		if (al.sym)
+		if (al.map)
 			goto found;
 	}
 found:
diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
index 3e9f336740fa..516d19fb999b 100644
--- a/tools/perf/util/symbol-elf.c
+++ b/tools/perf/util/symbol-elf.c
@@ -151,15 +151,15 @@ Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
 
 		gelf_getshdr(sec, shp);
 		str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
-		if (!strcmp(name, str)) {
+		if (str && !strcmp(name, str)) {
 			if (idx)
 				*idx = cnt;
-			break;
+			return sec;
 		}
 		++cnt;
 	}
 
-	return sec;
+	return NULL;
 }
 
 #define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \