I have installed Ubuntu 11.10 on a netbook (Intel 1.6 GHz and RAM 1 GB) with Windows XP. One week ago, Ubuntu stopped. That day had not installed any upgrade or any software.
When I try to start Ubuntu, I get is this message:
BusyBox v1.18.4 (Ubuntu 1:1.18.4-2ubuntu2) built-in shell (ash) Enter 'help' for a list of built-in commands. (Initramfs)
After a few seconds, I get the following error:
(Initramfs) udevd : timeout '/ sbin / blkid-o udev-p / dev / sda' udevd : timeout: killing '/ sbin / blkid-o udev-p / dev / sda' 
The second of these lines begins to repeat a lot of times, until finally it appears this line:
udevd : '/ sbin / blkid-o udev-p / dev / sda'  terminated by signal 9 (Killed)
Then the computer is locked and the only way I know to get out is by pressing CTRL+ALT+DEL to return to GRUB, boot Windows and close Windows.
For better understanding, I leave screenshots (click to enlarge):
This is my partition table disk:
/dev/sda1 → swap
/dev/sda2 → /, ext4
/dev/sda3 → /windows, ntfs
/dev/sda4 → /shared, fat32
I run "chkdsk" from Windows to check the Windows partitions (
/dev/sda4) and the result has been successful: no errors were found.
Then I tried booting Ubuntu in recovery mode and using previous versions of the kernel, but in all cases I have had the same error. Then I did a memory test (two passes) and no errors were found.
Finally I tried to start the netbook from a Live USB of Ubuntu 11.10 (created with UNetbootin), but I get the same error when I try to boot my Ubuntu installation from GRUB:
udevd : timeout: killing '/ sbin / blkid-o udev-p / dev / sda' 
I think I have a hardware failure on the hard drive, but I don't understand why this affects only the Linux partition and not the Windows partition.
I don't know what else I can do.