diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 117a1202a6b96ef9b664ac2085135afda3e568dc..bf2bcb8d7725eb4ccab66948bf167899e3bac3ef 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -2039,12 +2039,6 @@ static int parse_map_size(char *str)
 	unsigned long size, map_bits;
 	int ret;
 
-	strsep(&str, "=");
-	if (!str) {
-		ret = -EINVAL;
-		goto out;
-	}
-
 	ret = kstrtoul(str, 0, &size);
 	if (ret)
 		goto out;
@@ -2104,25 +2098,25 @@ static int parse_action(char *str, struct hist_trigger_attrs *attrs)
 static int parse_assignment(struct trace_array *tr,
 			    char *str, struct hist_trigger_attrs *attrs)
 {
-	int ret = 0;
+	int len, ret = 0;
 
-	if ((str_has_prefix(str, "key=")) ||
-	    (str_has_prefix(str, "keys="))) {
-		attrs->keys_str = kstrdup(str, GFP_KERNEL);
+	if ((len = str_has_prefix(str, "key=")) ||
+	    (len = str_has_prefix(str, "keys="))) {
+		attrs->keys_str = kstrdup(str + len, GFP_KERNEL);
 		if (!attrs->keys_str) {
 			ret = -ENOMEM;
 			goto out;
 		}
-	} else if ((str_has_prefix(str, "val=")) ||
-		   (str_has_prefix(str, "vals=")) ||
-		   (str_has_prefix(str, "values="))) {
-		attrs->vals_str = kstrdup(str, GFP_KERNEL);
+	} else if ((len = str_has_prefix(str, "val=")) ||
+		   (len = str_has_prefix(str, "vals=")) ||
+		   (len = str_has_prefix(str, "values="))) {
+		attrs->vals_str = kstrdup(str + len, GFP_KERNEL);
 		if (!attrs->vals_str) {
 			ret = -ENOMEM;
 			goto out;
 		}
-	} else if (str_has_prefix(str, "sort=")) {
-		attrs->sort_key_str = kstrdup(str, GFP_KERNEL);
+	} else if ((len = str_has_prefix(str, "sort="))) {
+		attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL);
 		if (!attrs->sort_key_str) {
 			ret = -ENOMEM;
 			goto out;
@@ -2133,12 +2127,8 @@ static int parse_assignment(struct trace_array *tr,
 			ret = -ENOMEM;
 			goto out;
 		}
-	} else if (str_has_prefix(str, "clock=")) {
-		strsep(&str, "=");
-		if (!str) {
-			ret = -EINVAL;
-			goto out;
-		}
+	} else if ((len = str_has_prefix(str, "clock="))) {
+		str += len;
 
 		str = strstrip(str);
 		attrs->clock = kstrdup(str, GFP_KERNEL);
@@ -2146,8 +2136,8 @@ static int parse_assignment(struct trace_array *tr,
 			ret = -ENOMEM;
 			goto out;
 		}
-	} else if (str_has_prefix(str, "size=")) {
-		int map_bits = parse_map_size(str);
+	} else if ((len = str_has_prefix(str, "size="))) {
+		int map_bits = parse_map_size(str + len);
 
 		if (map_bits < 0) {
 			ret = map_bits;
@@ -2187,8 +2177,14 @@ parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str)
 
 	while (trigger_str) {
 		char *str = strsep(&trigger_str, ":");
+		char *rhs;
 
-		if (strchr(str, '=')) {
+		rhs = strchr(str, '=');
+		if (rhs) {
+			if (!strlen(++rhs)) {
+				ret = -EINVAL;
+				goto free;
+			}
 			ret = parse_assignment(tr, str, attrs);
 			if (ret)
 				goto free;
@@ -4522,10 +4518,6 @@ static int create_val_fields(struct hist_trigger_data *hist_data,
 	if (!fields_str)
 		goto out;
 
-	strsep(&fields_str, "=");
-	if (!fields_str)
-		goto out;
-
 	for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX &&
 		     j < TRACING_MAP_VALS_MAX; i++) {
 		field_str = strsep(&fields_str, ",");
@@ -4620,10 +4612,6 @@ static int create_key_fields(struct hist_trigger_data *hist_data,
 	if (!fields_str)
 		goto out;
 
-	strsep(&fields_str, "=");
-	if (!fields_str)
-		goto out;
-
 	for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) {
 		field_str = strsep(&fields_str, ",");
 		if (!field_str)
@@ -4781,12 +4769,6 @@ static int create_sort_keys(struct hist_trigger_data *hist_data)
 	if (!fields_str)
 		goto out;
 
-	strsep(&fields_str, "=");
-	if (!fields_str) {
-		ret = -EINVAL;
-		goto out;
-	}
-
 	for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
 		struct hist_field *hist_field;
 		char *field_str, *field_name;
@@ -4795,9 +4777,11 @@ static int create_sort_keys(struct hist_trigger_data *hist_data)
 		sort_key = &hist_data->sort_keys[i];
 
 		field_str = strsep(&fields_str, ",");
-		if (!field_str) {
-			if (i == 0)
-				ret = -EINVAL;
+		if (!field_str)
+			break;
+
+		if (!*field_str) {
+			ret = -EINVAL;
 			break;
 		}
 
@@ -4807,7 +4791,7 @@ static int create_sort_keys(struct hist_trigger_data *hist_data)
 		}
 
 		field_name = strsep(&field_str, ".");
-		if (!field_name) {
+		if (!field_name || !*field_name) {
 			ret = -EINVAL;
 			break;
 		}