mirrors/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-05-03 19:26:01 -04:00
Code Issues Packages Projects Releases Wiki Activity

bcachefs: Fix a deadlock in btree_update_nodes_written()

Browse Source 
btree_node_lock_nopath() is something we'd like to get rid of, it's
always prone to deadlocks if we accidentally are holding other locks,
because it doesn't mark the lock it's taking in a path: we'll want to
get rid of it in the future, but for now this patch works it by calling
bch2_trans_unlock().

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet
2022-10-03 16:41:17 -04:00
parent 13bc41a715
commit 8aaee94d46
1 changed files with 11 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
fs/bcachefs/btree_update_interior.c
View File

@@ -650,6 +650,17 @@ static void btree_update_nodes_written(struct btree_update *as)
* we're in journal error state:
*/
/*
* Ensure transaction is unlocked before using
* btree_node_lock_nopath() (the use of which is always suspect,
* we need to work on removing this in the future)
*
* It should be, but get_unlocked_mut_path() -> bch2_path_get()
* calls bch2_path_upgrade(), before we call path_make_mut(), so
* we may rarely end up with a locked path besides the one we
* have here:
*/
bch2_trans_unlock(&trans);
btree_node_lock_nopath_nofail(&trans, &b->c, SIX_LOCK_intent);
mark_btree_node_locked(&trans, path, b->c.level, SIX_LOCK_intent);
path->l[b->c.level].lock_seq = b->c.lock.state.seq;