Kernel/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2025-01-18 03:06:43 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

bcachefs: Fix race between btree writes and metadata drop

Browse Source 
btree writes update the btree node key after every write, in order to
update sectors_written, and they also might need to drop pointers if one
of the writes failed in a replicated btree node.

But the btree node might also have had a pointer dropped while the write
was in flight, by bch2_dev_metadata_drop(), and thus there was a bug
where the btree node write would ovewrite the btree node's key with what
it had at the start of the write.

Fix this by dropping pointers not currently in the btree node key.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet 2023-11-28 19:26:23 -05:00
parent ef0beeb8dd
commit 2111f39459
1 changed files with 4 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
fs/bcachefs/btree_update_interior.c
View File

@ -2270,6 +2270,10 @@ int bch2_btree_node_update_key_get_iter(struct btree_trans *trans,
BUG_ON(!btree_node_hashed(b));
struct bch_extent_ptr *ptr;
bch2_bkey_drop_ptrs(bkey_i_to_s(new_key), ptr,
!bch2_bkey_has_device(bkey_i_to_s(&b->key), ptr->dev));
ret = bch2_btree_node_update_key(trans, &iter, b, new_key,
commit_flags, skip_triggers);
out: