Merge tag 'bcachefs-2024-06-12' of

Pull bcachefs fixes from Kent Overstreet:

 - fix kworker explosion, due to calling submit_bio() (which can block)
   from a multithreaded workqueue

 - fix error handling in btree node scan

 - forward compat fix: kill an old debug assert

 - key cache shrinker fixes

   This is a partial fix for stalls doing multithreaded creates - there
   were various O(n^2) issues the key cache shrinker was hitting [1].

   There's more work coming here; I'm working on a patch to delete the
   key cache lock, which initial testing shows to be a pretty drastic
   performance improvement

 - assorted syzbot fixes

Link: [1]

* tag 'bcachefs-2024-06-12' of
  bcachefs: Fix rcu_read_lock() leak in drop_extra_replicas
  bcachefs: Add missing bch_inode_info.ei_flags init
  bcachefs: Add missing synchronize_srcu_expedited() call when shutting down
  bcachefs: Check for invalid bucket from bucket_gen(), gc_bucket()
  bcachefs: Replace bucket_valid() asserts in bucket lookup with proper checks
  bcachefs: Fix snapshot_create_lock lock ordering
  bcachefs: Fix refcount leak in check_fix_ptrs()
  bcachefs: Leave a buffer in the btree key cache to avoid lock thrashing
  bcachefs: Fix reporting of freed objects from key cache shrinker
  bcachefs: set sb->s_shrinker->seeks = 0
  bcachefs: increase key cache shrinker batch size
  bcachefs: Enable automatic shrinking for rhashtables
  bcachefs: fix the display format for show-super
  bcachefs: fix stack frame size in fsck.c
  bcachefs: Delete incorrect BTREE_ID_NR assertion
  bcachefs: Fix incorrect error handling found_btree_node_is_readable()
  bcachefs: Split out btree_write_submit_wq