Cannot boot Archlinux Arm or Ubuntu Touch on Nexus 7 2013 wifi(flo)

[huiyiqun]

I bought a brand new flo recently from amazon.jp and install latest multirom from Multirom Manager.

I have tried to boot Ubuntu Touch which is installed from Multirom Manager and Archlinux Arm like this. They all failed and the screen is stick to Google.

I reboot to Internal Rom which is the official cm12.1 and cat last_kmsg but there is no fatel error.

Here is the info from bootloader:

PRODUCT NAME - flo
VARIANT - flo 16G
HW VERSION - rev_e
BOOTLOADER VERSION - FLO-04.05
CARRIER INFO - None
SERIAL NUMBER - 0ad2c574
SIGNING - yes
SECURE BOOT - enabled
LOCK STATE - unlocked

There is another interesting thing. When I flash cm12.1 to my flo, I tried official TWRP but it failed with mount error. I found with adb shell that /dev/block/mmcblock* nor /dev/block/platform/ exists.

It seems there is some difference between my flo and normal flo. but when I try modifed twrp for multirom, it works.

So why modified twrp could found block devices while official twrp could not? different kernel patch or kernel version?

I guess Archlinux Arm or Ubuntu Touch could not boot for the same reason.

[huiyiqun]

Sorry for my broken English.

Update: I just flashed cm11 as a secondary rom, it restarted againt immediately.

According to last_kmsg, it rebooted for waiting for /dev/block/platform/by-name/userdata for too long period.

[huiyiqun]

I flashed another cm12 as a secoundary rom, it booted correctly.

[huiyiqun]

I've found the problem with myself.

[    2.191772] mmc0: unrecognised EXT_CSD revision 7
[    2.191955] mmc0: error -22 whilst initialising MMC card

Here is the problem, which is fixed in TWRP for multirom in this commit.