: [ 0.710000] Creating 5 MTD partitions on "spi0.0":
: [ 0.720000] 0x000000000000-0x000000020000 : "u-boot"
: [ 0.720000] 0x000000020000-0x00000012ed38 : "kernel"
: [ 0.730000] mtd: partition "kernel" must either start or end on erase
: block boundary or be smaller than an erase block

我一直很想问，这种piggy back的打包方式，kernel要如何知道rootfs在哪里?

piggy back有很多种方式，最常用的是前面有super headerkernel可以自己读super header, 或是bootloader带参数给kernel, 至于detail，要去trace gen image的source code.例如: mkimage

了解，感谢