Created attachment 49912 [details] extraction from kernel log Since having instability problems with guest (XP/FreeBSD runs for at most for 2-3 hours) on Ubuntu AMD64 host, I've moved to vanilla 2.6.37.1., build it via make oldconfig, accepted defaults. VirtualBox is 4.0.4. It might work slightly better, but it crashed again (machine is Thinkpad W510 - Core i7). The log is attached. All file systems used are XFS. Guest is installed on external disc connected via eSATA. I've suspected RAM problems in the past and run memory test in DOS mode to check whole range. Test was repeated and run for few hours (approx 8). No problems detected. And the only time I see the instability is while using VirtualBox with guest, but this is also the only time RAM gets really used (up to 4x4GB available).
Today connection to FS failed even before Virtualbox has been started. New bug reported. *** This bug has been marked as a duplicate of bug 30802 ***