The kernel is yet unable to use the linux extended partition (type 0x85). The linux extended partition is just a dos extended partition with a different identifier, as not to confuse dos. Implementing the use of the linux extended partition requires the partition type to be known, and a check for its presence. Fix: Following is a diff of the original to a patched /sys/kern/subr_diskmbr.c:
Responsible Changed From-To: freebsd-bugs->sheldonh I'll commit something close to this once it's made it through a kernel build. :-)
Responsible Changed From-To: sheldonh->freebsd-bugs I seem to remember either bde or msmith being unhappy with the change for some reason. Shame on me for not copying the message to the audit trail. Anyway, I can't follow it up now, so throw it open to the peanut gallery. :-) .
The patch is too old and doesn't apply (the file doesn't exist anymore). In any case I haven't heard of problems mounting modern ext2/3/4.