diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 27821480105e..217ef481fbbb 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -1301,7 +1301,7 @@ static int parse_pred(const char *str, void *data,
 		/* go past the last quote */
 		i++;
 
-	} else if (isdigit(str[i])) {
+	} else if (isdigit(str[i]) || str[i] == '-') {
 
 		/* Make sure the field is not a string */
 		if (is_string_field(field)) {
@@ -1314,6 +1314,9 @@ static int parse_pred(const char *str, void *data,
 			goto err_free;
 		}
 
+		if (str[i] == '-')
+			i++;
+
 		/* We allow 0xDEADBEEF */
 		while (isalnum(str[i]))
 			i++;
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 9eaf07f99212..99592c27465e 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -865,7 +865,7 @@ fetch_store_strlen(unsigned long addr)
 	u8 c;
 
 	do {
-		ret = probe_mem_read(&c, (u8 *)addr + len, 1);
+		ret = probe_kernel_read(&c, (u8 *)addr + len, 1);
 		len++;
 	} while (c && ret == 0 && len < MAX_STRING_SIZE);