Thanks. I went back to my original config, and checked each of those options. I think the issue was that I had CONFIG_PCI_AARDVARK=y, but CONFIG_PHY_MVEBU_A3700_COMPHY=m. According to the help for that option, it seems required to use PCIe, along with some other buses. It makes sense then that it couldn’t mount the rootfs if a module required for doing so was stored there. I changed it to ‘y’ and it’s able to boot again.
