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I have a 10.10 Xubuntu installed with the kernel 2.6.35-22 but for work I need to make a downgrade to, for that, I compiled the kernel with all modules I need (or so I think) and when loading, I get:

mount: mounting none on /dev failed: no such device 
W: devtmpfs not available, falling back to tmpfs for /dev 
WARNING bootdevice may be renamed. Try root=/dev/hda1
Gave up waiting for root device. Common problems:
- Boot args (cat /proc/cmdline )
- Check rootdelay= (did the system wait long enough?)
- Check root= (did the system wait for the right device?)
- Missing modules (cat /proc/modules; ls /dev)
ALERT! /dev/sda1 does not exist. Dropping to a shell! 

After that sends me to busybox and making cd on /dev does not appear any sda, hda or by-uuid/path/label

share|improve this question

Sounds like you're missing CONFIG_DEVTMPFS

Hand selecting modules is very difficult these days (I miss the 1.0 days). I would just use the default Ubuntu kernel build system to build one with "everything", wait forever for it to build, then move on to better activities. :)

You could also just downgrade the kernel to a previous Ubuntu version if you can find the version you want. I can never remember how to do it but it is a question that has been answered many times in the past if you want to search.

share|improve this answer
Ok i have been trying everything you say (except as to download the kernel from git) unfortunately i could not get it to boot and CONFIG_DEVTMPFS not exist in this kernel, has any other suggestions? i'm getting a little nervous with this – JoseMuekaz Jul 11 '12 at 8:09
Have you tried one of the "build kernel" tutorials? Like here – CR. Jul 12 '12 at 12:50

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