@pppig236 In the case of Linksys devices, the kernel partition overlaps the rootfs partition. If you do not define all partitions this way manually, then partition overlap does not occur:
[ 1.228654] Creating 20 MTD partitions on "qcom_nand.0":
[ 1.234914] 0x000000000000-0x000000180000 : "0:sbl1"
[ 1.242480] 0x000000180000-0x000000280000 : "0:mibib"
[ 1.246741] 0x000000280000-0x000000600000 : "0:qsee"
[ 1.254421] 0x000000600000-0x000000680000 : "0:devcfg"
[ 1.256256] 0x000000680000-0x000000700000 : "0:rpm"
[ 1.261352] 0x000000700000-0x000000780000 : "0:cdt"
[ 1.266018] 0x000000780000-0x000000800000 : "0:appsblenv"
[ 1.270893] 0x000000800000-0x000000980000 : "0:appsbl"
[ 1.277326] 0x000000980000-0x000000a00000 : "0:art"
[ 1.281529] 0x000000a00000-0x000000a80000 : "0:ethphyfw"
[ 1.286200] 0x000000a80000-0x000000b00000 : "u_env"
[ 1.291815] 0x000000b00000-0x000000b40000 : "s_env"
[ 1.296143] 0x000000b40000-0x000000b80000 : "devinfo"
[ 1.301033] 0x000000b80000-0x000001380000 : "kernel"
[ 1.313348] 0x000001380000-0x000005d80000 : "rootfs"
[ 1.386409] 0x000005d80000-0x000006580000 : "alt_kernel"
[ 1.399094] 0x000006580000-0x00000af80000 : "alt_rootfs"
[ 1.468373] 0x00000af80000-0x00000b380000 : "sysdiag"
[ 1.472684] 0x00000b380000-0x00001f080000 : "syscfg"
[ 1.767622] 0x00001f080000-0x00001f580000 : "app_data"
and all serial port installation steps do not apply.
This is currently an issue with the MR7350 and MR7500.