Tango & Crash

Last night I had the strangest of errors on my Ubuntu laptop.
The whole file system become write only, I don't have the slightest clue why, it was turned on for 7 days, the load wasn't that high (downloaded a couple of Bit Torrents over the weekend), and no new kernel or strange updates installed (just the ones that Ubuntu released yesterday)

Had to reboot it to get it back to normal.

Discovered the problem when tried to make the daily rsync backup for the iTunes files from my Quicksilver to the laptop, when I got this error message:

Harmonic Lyrics.zip
     3735453 100%    2.92MB/s    0:00:01 (xfer#1, to-check=5956/5957)
rsync: mkstemp "/home/esteban/Music/.Harmonic Lyrics.zip.nrsYU4" failed: Read-only file system (30)
iTunes Library
    10409730 100%    6.22MB/s    0:00:01 (xfer#2, to-check=5955/5957)
iTunes Music Library.xml
     9629811 100%    6.21MB/s    0:00:01 (xfer#3, to-check=5954/5957)
iTunes Music/Iggy Pop/Iggy Pop & The Stooges - No fun.mp3
     6184086 100%    7.62MB/s    0:00:00 (xfer#4, to-check=4305/5957)
iTunes Music/The Ramones 1976-1991/06 - Ramones - End of the century - 1980/08-ramones-i_cant_make_it_on_time-rh.mp3
     4205268 100%    4.09MB/s    0:00:00 (xfer#5, to-check=1359/5957)
iTunes Music/The Ramones 1976-1991/06 - Ramones - End of the century - 1980/09-ramones-this_aint_havana-rh.mp3
     3957656 100%    3.22MB/s    0:00:01 (xfer#6, to-check=1358/5957)
rsync: mkstemp "/home/esteban/Music/.iTunes Library.VFVbKu" failed: Read-only file system (30)
rsync: mkstemp "/home/esteban/Music/.iTunes Music Library.xml.NxsRlW" failed: Read-only file system (30)
rsync: mkstemp "/home/esteban/Music/iTunes Music/Iggy Pop/.Iggy Pop & The Stooges - No fun.mp3.AU0nJo" failed: Read-only file system (30)
rsync: mkstemp "/home/esteban/Music/iTunes Music/The Ramones 1976-1991/06 - Ramones - End of the century - 1980/.08-ramones-i_cant_make_it_on_time-rh.mp3.TXyUmR" failed: Read-only file system (30)
rsync: mkstemp "/home/esteban/Music/iTunes Music/The Ramones 1976-1991/06 - Ramones - End of the century - 1980/.09-ramones-this_aint_havana-rh.mp3.SXADbk" failed: Read-only file system (30)

sent 8954741 bytes  received 88556 bytes  369114.16 bytes/sec
total size is 22799809274  speedup is 2521.18
rsync error: some files could not be transferred (code 23) at /SourceCache/rsync/rsync-35.2/rsync/main.c(992) [sender=2.6.9]

At the moment I was logged in on the console (Tango boots to a non graphical login, and I start Gnome via 'startx', never a problem with that either)
On the console I was logged it, tried to do a 'touch test.txt' & a 'sudo touch test.txt', both failed with the same read only file system error.
That's when I rebooted, after that, and to this moment (being on all night, with Evolution open, and watched a movie on it)
It the HDD that is effing with me? It is brand new...

Looking for clues on the /var/log/messages file, found this entry:

Oct 14 00:09:16 tango kernel: [682988.488445] SysRq : HELP : loglevel0-8 reBoot Crashdump tErm Full kIll saK showMem Nice powerOff showPc show-all-timers(Q) unRaw Sync showTasks Unmount shoW-blocked-tasks 

Googling a bit for it looks like I might have enabled a SysRQ keyboard combo that had turned the whole file system read only, that's the only explanation I can come up with at the moment.

Linux is fun for me