I urgently need help reactivating my N900!

Following situation:

After powering on the device starts normally until the desktop tries to load all widgets. Most of the widgets aren't visible but there is darkened space where the widgets sit. After some seconds the desktop restarts and again tries to load all widgets. Looks like there is more to see from the widgets with every restart. This happens several times then the device reboots and the procedure starts again.
I randomly can access the status bar or the system menu (via the button on the long side of the N900). But it's coming very slow and desktop restarts before I can select anything.

This happened before:

I installed Hexen2 and Jazz Jackrabbit from testing and and started both without having the data files installed. First I tried Hexen2 which obviously did nothing then I tried JJ which also didn't open any window. But then I realized that the load went straight up and the device got very slow. Visiting 'top' I detected a process "mv home home" .
I looked into /home and there was a new subfolder "home", i.e. /home/home. I immediately killed the mv process and checked the content of /home/home, which was already grown to 1,2GB. The content was the directory structure and already a lot of files from /home. But as far as I could see, all files were still existing in the former places. So nothing seemed to be removed yet. I also didn't remove anything, checked the process list again and wasn't sure wether there were still some processes doing something weird. So I decided to reboot the device. Imagine what happened after booting .....

Does anyone know how to go around hildon-desktop when booting? I think I just need access to the shell and should be able to repair it. But I just can't find any hints how to prevent the x-windows from starting.

Or are there any other hints what I could do? I know, I could just reflash the device but that's the last thing I'd like to do. I'd lose a lot of settings and data.

Please help!

You could try enabling R&D Mode, with the "no-lifeguard-reset" flag set through flasher-3.5. This should, hopefully, prevent any more restarts; but you'll have to be quick enough in starting xterm.

If you haven't backed up even though you installed stuff from testing, you really are likely to lose data after reflashing. Backing up and reflashing are the twin pillars of not being afraid when running your tablet. If anyone I knew well lost data under similar circumstances (including myself), I would tell them that they got what they deserved.

So I can set this flag without actually flashing the device? I was thinking this was only possible in addition to a flashing process.

So I might also try to set some bootflags? Are there any docs describing valid boot parameters? Like a runlevel for example?

I knew I'd get some kicks in the a.... by asking this.

I DO backup my data, even if the last one is already some days old and I'm quite experienced with linux and command line. That's why I have no fear installing apps from ~testing. ~devel I had enabled with my very first steps with the device but after first reflash I never used it again. Too much really broken stuff in there!

So except for some SMS and my newly setup shoppinglist in mulitlists, there's nothing valuable I'd lose, but it still takes hours to get back to my current setup, I guess.

Yes, "flasher-3.5[.exe] --set-rd-flags=no-lifeguard-reset" will enable RD-Mode (with the no-lifeguard-reset flag) without requiring you to reflash your device. I also wrote a lame program that allows for it to be done on the device itself, but it is rather unreliable...

You could try. flasher-3.5 also has a "--boot" option which tells the bootloader, NOLO, to start the kernel with a cmdline given by you. I'm not sure if you are required to specify a kernel image to pass along with it, however.

If it helps, this is the default cmdline of my N900 (running titan's kernel-power):

Thank you very much!
Even if I don't understand most of the arguments given in your command line, I see the very first entry and this reminds me of an old trick getting access to cmdline by bypassing the complete init process....
I'll give it a try ....

At least I'd like to do a last backup of data and then reflash the device. Even better would be I could restore a working state and keep on using it without flashing. But I desperately need commandline access now.

Could anyone please give me the complete command line from bootmanager using the standard kernel, latest release? That would be very helpful. It should be visible somewhere in /proc, probably /proc/cmdline but I just don't know how this works on maemo.

Status update: at least I can mount "MyDocs" to my PC and copy the files in there, even if the device did one 'reboot' after plugging the USB cable in. Will say, it was powered off, I plugged the cable in, it powered on, the yellow LED flickered then it rebooted and then the partition popped up on my desktop.

Something weird is going on in there ....

Update: changing the init-entry in commandline doesn't work as expected . Good point is, the N900 falls back to normal behaviour automatically.
OK, next try: disabling the watchdog and trying to call xterm. will be tricky as I don't see which desktop icon I have to click on but when at least the device doesn't reboot I have chances picking the right one. Luckily the icon sits on the first desktop which is shown on startup. If it didn't I'd have no chance at all calling it.

Update 2: set R&D mode with flag "no-lifeguard-reset" and this one nearly did what I expected it to do.

Calling xterm from desktop icon didn't work. At some point I realized that the desktop seemed to be completely crashed and also didn't restart. No icon and neither the status bar were usable. But the system menu still popped up when using the button. And there is a point called "top in xterm". One step closer ....

It took some time but then there was a top running in an xterm. top itself ain't pretty helpful in this situation but closing top didn't close the xterm as it usually does. There it was

Calling "root" to gain root access still worked and midnight commander did so too. I checked the folders in /home/user again and compared to the ones in /home/home/user but in the latter one there were no files that were not in /home/user too.

I guess one of the latest updates really broke my desktop, but I have no idea which one it could be.

Sadly, at some point when backing up my data the device hung up, so I had to remove the battery. Will do again the same procedure and try to do the rest of the backup. Then copy the stuff to my PC, inspect it and when nothing seems to help, I'll reflash.

I guess, I'm giving up. I have absolutely no idea on which point the system got broken. Actual state is following:

desktop starts, restarts three or four times then the desktop is shown, all icons and widgets on one screen but no window manager. I can click on the instances of DCEW but not on any icon. The status bar works, the plugins like system monitor get updated and the trick with calling xterm via top also still works. But I don't have any idea of what could be broken.

After having backed up all data I'll play a little with the broken system and then reflash.

Oh my god!
All my tricks didn't help -- I had to reflash. Luckily flashing FIASCO image helped and there was no need to overwrite the MMC too. After flashing I got prompted by the initial screen but I only had to confirm the settings like date and timezone.

Then I had a completely empty desktop. OK, switching to the next one I saw the standard items like ovi store and that stuff. Immediately I restored my latest backup, the device rebooted but my icons and widgets still were not there. Even in the list of widgets no DCEW or Personal Dataplan. Looks like I have to reinstall all apps! Actually it's reinstalling all apps, saying it would take more than 700MB! I just hope it's not the volume of the download, this could break my data plan.

Bbut looking at the apps getting downloaded and installed is fun in some way: The desktop gets slowly filled with icons again, it's kind of magic I just hope that there is nothing which breaks my desktop right again. I would crush that beast!