Re: [syzbot] [btrfs?] BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low! (5)

[Kent Overstreet]

The issue here is that bcachefs can lock many more btree nodes 
simultaneously, more than lockdep can track. The fix is to switch to a
single lockdep map in the btree_trans for "we have any btree nodes
lock"; it's going in this merge window.

#syz fix: bcachefs: Add lockdep support for btree node locks