Comment 16 for bug 352197

Another "me, too" for this bug.
Ubuntu 9.04 64bit - SATA AHCI mode - ext4 fs
WD Velociraptor (ext4fs: /, Swap, /Data)
WD Caviar Black 1TB (ext4fs: /home)
WD 640GB (ext4fs: /Backup)

I recently built a new system using an EVGA 760 Classified MB, i7 920cpu, 12GB triple ch DDR3 and 300GB Velociraptor. I installed the OS after setting the BIOS to SATA AHCI mode (needed hot swapping capabilities). Everything worked fine for about 1 month until last night. I was doing a very large (200GB+) grsync backup of my /home partition to my WD640GB backup drive. At some point in the backup the system froze. No combination of keyboard tricks (ctl+alt+backspace, or alt+print screen+REISUB) would restart X or reboot the OS. I had to resort to killing power.

On reboot, the one of my BIOS screens reported "Port 00:" during what I will call the AHCI check. The Velociraptor system drive would not boot. When, I went back into the BIOS setup, I saw that the BIOS did not even see the Velociraptor. I assumed the crash and hard power down had corrputed some critical system files. I removed the Velociraptor boot drive and replaced it with a WinXP 64 boot drive (also set for AHCI mode) and was able to boot up a Windows system with no problem. I then tested the Velociraptor with SpinRite 6 and its a good drive.

I decided to try and reboot the Ubuntu system by changing the BIOS SATA setting to "IDE" mode. This worked. Ubuntu was able to start after it found a few errors on the / partition, corrected them, and finished booting. Ubuntu 9.04/64 now seems to be working fine in "IDE" mode.

After reading through this thread, it seems that I have been bitten by this AHCI bug when I was doing the very large rsync file backup; although, I have to add that this wasn't the first time, I did such a large backup on this new system without problems.