hypfs_create_cpu_files(): add missing check for hypfs_mkdir() failure

Signed-off-by: Al Viro <[email protected]>

Author: Al Viro

arch/s390/hypfs/hypfs_diag_fs.c

@@ -208,6 +208,8 @@ static int hypfs_create_cpu_files(struct dentry *cpus_dir, void *cpu_info)
 	snprintf(buffer, TMP_SIZE, "%d", cpu_info__cpu_addr(diag204_get_info_type(),
 							    cpu_info));
 	cpu_dir = hypfs_mkdir(cpus_dir, buffer);
+	if (IS_ERR(cpu_dir))
+		return PTR_ERR(cpu_dir);
 	rc = hypfs_create_u64(cpu_dir, "mgmtime",
 			      cpu_info__acc_time(diag204_get_info_type(), cpu_info) -
 			      cpu_info__lp_time(diag204_get_info_type(), cpu_info));