Bcachefs Squeezes More Fixes Into Linux 6.12

Ahead of the expected final Linux 6.12 stable kernel release this weekend, a last round of Bcachefs file-system fixes were submitted today for this next kernel version.

This latest round of Bcachefs fixes contain a number of small Syzbot fixes brought up by the Syzkaller kernel fuzzer. There is also a fix for a case where the btree write buffer wasn't being flushed on the shutdown path and thus leading to shutting down while operations were still in flight. That shutdown fix is expected to address a range of problems.

While Bcachefs has been hunting down remaining bugs and reported a 40% drop over the prior month, Bcachefs lead developer Kent Overstreet warned in today's pull request that more bugs are on the horizon. When enabling Bcachefs self-healing support it's expected to bring in another wave of Syzbot bugs. Overstret explained:

"test dashboard is looking good, rebasing to rc6 fixed the crazy hangs we were seeing on rc1...

(and they were crazy; processes were getting stuck on inode lock when lockdep said nothing was holding it).

this fixes one minor regression from the btree cache fixes in the last pull request (in the scan_for_btree_nodes repair path) - and the shutdown path fix is the big one here, in terms of bugs closed.

so I would say things are slowing down here, except now that I've got an easy way to run syzbot reproducers I'm noticing that we're losing a lot of coverage because mainly we're mostly bailing out when we see something corrupt. When self healing is flipped on for more stuff there's probably going to be another flood of syzbot stuff..."

See the pull request for the latest batch of Bcachefs fixes.