目前我正在为我们的定制设备进行 Android 更新。从已知运行的 Android 4.3（带 u-boot 2015.04 和 Linux 内核 3.2）更新到 Android 7.1.2（带 u-boot 2015.07 Linux 内核 4.5）。已知 u-boot 2015.07 和 Linux 内核 4.5 可在我们的定制设备上运行。在将u-boot和Linux内核集成到Android 7.1.2中时，Linux内核无法启动。
这是日志：
[ 3.667772] sr_init: No PMIC hook to init smartreflex
[ 3.673780] sr_init: platform driver register failed for SR
[ 3.716721] vdd5_reg: disabling
[ 3.720220] regulator-wl18xx-wl-en: disabling
[ 3.724826] regulator-wl18xx-bt-en: disabling
[ 3.959011] usb 2-1: new high-speed USB device number 2 using musb-hdrc
[ 4.099854] usb 2-1: New USB device found, idVendor=0424, idProduct=2513
[ 4.106939] usb 2-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[ 4.120895] hub 2-1:1.0: USB hub found
[ 4.126728] hub 2-1:1.0: 3 ports detected
[ 4.311994] EXT4-fs (mmcblk0p2): mounted filesystem with ordered data mode. Opts: (null)
[ 4.320977] VFS: Mounted root (ext4 filesystem) on device 179:2.
[ 4.331395] devtmpfs: error mounting -2
[ 4.336827] Freeing unused kernel memory: 452K (c09b5000 - c0a26000)
[ 4.348323] Starting init: /etc/init exists but couldn't execute it (error -13)
[ 4.377888] Kernel panic - not syncing: No working init found. Try passing init= option to kernel. See Linux Documentation/init.txt for guidance.
[ 4.391965] ---[ end Kernel panic - not syncing: No working init found. Try passing init= option to kernel. See Linux Documentation/init.txt for guidance.
[ 77.048831] random: nonblocking pool is initialized
root 的文件系统（标签为 system）是 ext4 格式。内核构建时，里面有/bin/sh、/etc/init/，但没有/sbin/文件夹和/bin/init /etc/init文件。我尝试将权限更改为任何人都可以执行这些文件，但它不起作用。有人知道这有什么问题吗？
编辑：我认为主要问题是文件系统未安装。
[ 4.295699] EXT4-fs (mmcblk0p2): mounted filesystem with ordered data mode. Opts: (null)
[ 4.304608] VFS: Mounted root (ext4 filesystem) on device 179:2.
[ 4.314750] devtmpfs: error mounting -2
有谁知道导致此错误的原因是什么？