btree_root entries for unknown btree IDs are created during recovery, before reading those btree roots.
But btree_node_scan may find btree nodes with unknown btree IDs when we haven't seen roots for those btrees. Reported-by: [email protected] Signed-off-by: Kent Overstreet <[email protected]> --- fs/bcachefs/btree_cache.c | 11 ++++++++--- fs/bcachefs/btree_cache.h | 9 +++++++-- 2 files changed, 15 insertions(+), 5 deletions(-) diff --git a/fs/bcachefs/btree_cache.c b/fs/bcachefs/btree_cache.c index 36dfa6a48aa6..1f06e24e53fc 100644 --- a/fs/bcachefs/btree_cache.c +++ b/fs/bcachefs/btree_cache.c @@ -1406,9 +1406,14 @@ void bch2_btree_id_level_to_text(struct printbuf *out, enum btree_id btree, unsi void bch2_btree_pos_to_text(struct printbuf *out, struct bch_fs *c, const struct btree *b) { bch2_btree_id_to_text(out, b->c.btree_id); - prt_printf(out, " level %u/%u\n ", - b->c.level, - bch2_btree_id_root(c, b->c.btree_id)->level); + prt_printf(out, " level %u/", b->c.level); + struct btree_root *r = bch2_btree_id_root(c, b->c.btree_id); + if (r) + prt_printf(out, "%u", r->level); + else + prt_printf(out, "(unknown)"); + prt_printf(out, "\n "); + bch2_bkey_val_to_text(out, c, bkey_i_to_s_c(&b->key)); } diff --git a/fs/bcachefs/btree_cache.h b/fs/bcachefs/btree_cache.h index 6cfacacb6769..dcc34fe4996d 100644 --- a/fs/bcachefs/btree_cache.h +++ b/fs/bcachefs/btree_cache.h @@ -128,14 +128,19 @@ static inline struct btree_root *bch2_btree_id_root(struct bch_fs *c, unsigned i } else { unsigned idx = id - BTREE_ID_NR; - EBUG_ON(idx >= c->btree_roots_extra.nr); + /* This can happen when we're called from btree_node_scan */ + if (idx >= c->btree_roots_extra.nr) + return NULL; + return &c->btree_roots_extra.data[idx]; } } static inline struct btree *btree_node_root(struct bch_fs *c, struct btree *b) { - return bch2_btree_id_root(c, b->c.btree_id)->b; + struct btree_root *r = bch2_btree_id_root(c, b->c.btree_id); + + return r ? r->b : NULL; } const char *bch2_btree_id_str(enum btree_id); /* avoid */ -- 2.45.2
