Cannot boot raspi

[mattanl]

Hi,
Today, after my xbmc (running on raspbian) got stucked, I turned off and then on my raspi.
Now, it fails to start, showing the messages:

No filesystem could mount root, tried: ext4
Indeed it is in host mode hprt0 = 00001101
Kernel panic - not syncing: VPS: Unable to mount root fs on unknown-block(179,2)
[<c0013f30>] (unwind_backtrace+0x0/0xf0) from [<c0374020>] (panic+0x74/0x1a8)
[<c0374020>] (panic+0x74/0x1a8) from [<c04bcc10>] (mount_block_root+0x1e8/0x248)
[<...>] (mount_block_root+...) from [<...>] (mount_root+...)
[<...>] (mount_root+...) from [<...>] (prepare_namespace+...)
[<...>] (prepare_namespace+...) from [<...>] (kernel_init+...)
[<...>] (kernel_init+...) from [<...>] (kernel_thread_exit+...)
PANIC: VPS: Unable to mount root fs on unknown-block(179,2)

Entering kdb (current=0xc7820c80, pid 1) due to Keyboard Entry
kdb>

Is there something I can do, or do I have to start everything from the beginning? (it will cancel my ~10-20 hours work...)

Thanks.

[JeremyF]

The root filesystem (the non-boot partition) looks like it got seriously corrupted. You could try to recover it by sticking the card in a Linux box and running fsck on it.

[mahjongg]

If you do not have a linux computer, you can temporarily create one by using a "Linux live distro", its a CD (or DVD) you can boot to get a working linux system (without installing anything)

You can download an "ISO file", with the Linux distribution of your choice, (for example Ubuntu), then burn it to a CD/DVD with the "burn as image" option of your CD-writer software.

Or you can buy a linux magazine that has a cover CD, with a linux live version on it.

Or for a few dollar you can mail order one from many different sources all over the world.

[mattanl]

Thanks for your reply!
I do not have linux installed (only windows), so I assume that the achieving of a linux (in one of the ways you suggested) will take more than starting from the beginning.
The most of the time, i spent to build xbmc for my weezy debian.
Is there a way to install it without building it?
Thanks again!

[obcd]

You could try openELEC or RaspBMC, but I have no idea how up to date the xbmc in those is.
You better consider cross compiling for a large program like xbmc.
It probably takes ages to compile it on the Pi?
Virtualbox is another nice alternative to install a linux distro and run it from within windows.
The Pi doesn't seem to like it if you simply cut the power without first shutting down it's OS. Sometimes it corrupts the sd card image. So, it's best to have a backup of it, just in case.

[mattanl]

It takes more than 5 hours to compile it. Can't be sure exectly how much time it took since I left it for the night...
Thanks a lot for your answers!

[pluggy]

Thanks for your reply!
I do not have linux installed (only windows), so I assume that the achieving of a linux (in one of the ways you suggested) will take more than starting from the beginning.
The most of the time, i spent to build xbmc for my weezy debian.
Is there a way to install it without building it?
Thanks again!

You don't need to install Linux to use Linux on your PC. Download it (Ubuntu is good) http://www.ubuntu.com/
Burn it to a CD and then boot from the CD. It works directly from the CD and needn't involve changing anything on your PC. Having an operating system that can directly read the Pi's SD cards is a great liberator.

Downloading a copy assuming you have a half decent internet connection takes a few minutes, another few minutes for burning it to a disk and away you go. If you choose to install it, its default is to shrink the windows partition to make room and make the system dual boot. You choose whether you want Linux or Windows when you turn your pc on. You can read and write your windows files from the linux side if you wish (but not vice versa). Since Ubuntu is based on Debian, it works a lot like the Pi.

When you get used to it you can cross compile stuff (not trivial unfortunately) for the Pi and have the benefit of a fast processor (the one in your PC) doing the donkey work of compilation.