--- zzzz-none-000/linux-4.4.271/init/do_mounts.c	2021-06-03 06:22:09.000000000 +0000
+++ hawkeye-5590-750/linux-4.4.271/init/do_mounts.c	2023-04-19 10:22:30.000000000 +0000
@@ -290,7 +290,9 @@
 }
 EXPORT_SYMBOL_GPL(name_to_dev_t);
 
-static int __init root_dev_setup(char *line)
+/* this isn't static anymore, as we need to have this function available for
+ * mtdram1= param parsing in our mtd code -PHU*/
+int __init root_dev_setup(char *line)
 {
 	strlcpy(saved_root_name, line, sizeof(saved_root_name));
 	return 1;
@@ -438,7 +440,7 @@
 out:
 	put_page(page);
 }
- 
+
 #ifdef CONFIG_ROOT_NFS
 
 #define NFSROOT_TIMEOUT_MIN	5
@@ -583,12 +585,31 @@
 		goto out;
 
 	/* wait for any asynchronous scanning to complete */
-	if ((ROOT_DEV == 0) && root_wait) {
+	if ((ROOT_DEV == 0) && root_wait && saved_root_name[0]) {
 		printk(KERN_INFO "Waiting for root device %s...\n",
 			saved_root_name);
 		while (driver_probe_done() != 0 ||
 			(ROOT_DEV = name_to_dev_t(saved_root_name)) == 0)
 			msleep(100);
+
+		async_synchronize_full();
+	} else if (config_enabled(CONFIG_MTD_ROOTFS_ROOT_DEV) &&
+			(ROOT_DEV == 0) && root_wait) {
+		pr_info(KERN_INFO "Waiting for root device ...\n");
+		/*
+		 * Though MMC devices get detected before kernel
+		 * reaches here, GPT partition table parsing happens
+		 * later. Since we assume the GPT partition "rootfs",
+		 * as the device to mount the Root FS from, the
+		 * "root=xxx" command line option might not be
+		 * present resulting in 'saved_root_name' being NULL.
+		 * Hence, don't try to do 'name_to_dev_t' on it.
+		 * Eventually, ROOT_DEV will get updated by the GPT
+		 * parsing code and we will break out of this loop.
+		 */
+		while (driver_probe_done() != 0 || ROOT_DEV == 0)
+			msleep(100);
+
 		async_synchronize_full();
 	}
 
@@ -633,6 +654,7 @@
 	if (err)
 		return err;
 
+#if 0
 	if (IS_ENABLED(CONFIG_TMPFS) && !saved_root_name[0] &&
 		(!root_fs_names || strstr(root_fs_names, "tmpfs"))) {
 		err = shmem_init();
@@ -640,6 +662,9 @@
 	} else {
 		err = init_ramfs_fs();
 	}
+#else
+	err = init_ramfs_fs();
+#endif
 
 	if (err)
 		unregister_filesystem(&rootfs_fs_type);