Merge tag 'bcachefs-2024-11-07' of git://evilpiepirate.org/bcachefs

Pull bcachefs fixes from Kent Overstreet:
 "Some trivial syzbot fixes, two more serious btree fixes found by
  looping single_devices.ktest small_nodes:

   - Topology error on split after merge, where we accidentaly picked
     the node being deleted for the pivot, resulting in an assertion pop

   - New nodes being preallocated were left on the freedlist, unlocked,
     resulting in them sometimes being accidentally freed: this dated
     from pre-cycle detector, when we could leave them locked. This
     should have resulted in more explosions and fireworks, but turned
     out to be surprisingly hard to hit because the preallocated nodes
     were being used right away.

     The fix for this is bigger than we'd like - reworking btree list
     handling was a bit invasive - but we've now got more assertions and
     it's well tested.

   - Also another mishandled transaction restart fix (in
     btree_node_prefetch) - we're almost done with those"

* tag 'bcachefs-2024-11-07' of git://evilpiepirate.org/bcachefs:
  bcachefs: Fix UAF in __promote_alloc() error path
  bcachefs: Change OPT_STR max to be 1 less than the size of choices array
  bcachefs: btree_cache.freeable list fixes
  bcachefs: check the invalid parameter for perf test
  bcachefs: add check NULL return of bio_kmalloc in journal_read_bucket
  bcachefs: Ensure BCH_FS_may_go_rw is set before exiting recovery
  bcachefs: Fix topology errors on split after merge
  bcachefs: Ancient versions with bad bkey_formats are no longer supported
  bcachefs: Fix error handling in bch2_btree_node_prefetch()
  bcachefs: Fix null ptr deref in bucket_gen_get()