Arch Linux

Thermodynamic

Member

From: Germany

Registered: 2022-03-29

Posts: 2

Failed to mount UUID on real root, mmc_select_hs400 error

Hello dear people,

upon a fresh install on my Lenovo IdeaPad 1, model 11ADA05 with Ramaxel 64 GB eMMC storage, booting failed and dropped me into the emergency shell.

ERROR: Failed to mount 'UUID=XYZ' on real root

When watching the boot process, the following errors appear before being dropped into the emergency shell:

mmc0: mmc_select_hs400 failed, error -110

Upon research error -110 corresponds to a timeout.

After trying other Distros (Endeavour, Cachy, vanilla Arch) the error persisted, despite changing filesystem type, partition format and bootloader.

What solved the boot problem (for now) was rolling back to an older kernel from the Arch package archive. Then any install worked with

linux-lts 6.6.72-1

Any Kernel with higher version than 6.6 would show the same behavior, vanilla or custom variants.

How can I dig deeper into finding the exact issue with newer kernels?

Kind regards and thanks in advance.

Last edited by Thermodynamic (2025-06-03 17:00:39)

jl2

Member

From: 47° 18' N 8° 34' E

Registered: 2022-06-01

Posts: 726

Website

Re: Failed to mount UUID on real root, mmc_select_hs400 error

https://wiki.archlinux.org/title/Bisect … s_with_Git
https://wiki.archlinux.org/title/Kernel … ild_system

Use linux-git and bisect between v6.6.* and v6.7.0.
Should require around like 12 builds, which will probably take forever on your system.

You can cut out kernel modules:
https://wiki.archlinux.org/title/Modprobed-db
and applying the list: https://wiki.archlinux.org/title/Modpro … l_PKGBUILD

If it takes too long to compile, send me the modprobed list and I'll compile it for you when I have the time.

Last edited by jl2 (2025-06-06 11:48:29)

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Why I run Arch? To "BTW I run Arch" the guy one grade younger.
And to let my siblings and cousins laugh at Arsch Linux...