From e75993b0bf8baa48b2e96d693852191f63b615fd Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Tue, 11 Mar 2025 09:04:09 -0400 Subject: [PATCH] bcachefs: Fix BCH_ERR_data_read_csum_err_maybe_userspace in retry path When we do a read to a buffer that's mapped into userspace, it's possible to get a spurious checksum error if userspace was modified the buffer at the same time. When we retry those, they have to be bounced before we know definitively whether we're reading corrupt data. But the retry path propagates read flags differently, so needs special handling. Signed-off-by: Kent Overstreet --- fs/bcachefs/io_read.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/bcachefs/io_read.c b/fs/bcachefs/io_read.c index 797c29bde9b6..17bc413c27ba 100644 --- a/fs/bcachefs/io_read.c +++ b/fs/bcachefs/io_read.c @@ -1291,6 +1291,9 @@ void __bch2_read(struct bch_fs *c, struct bch_read_bio *rbio, swap(bvec_iter.bi_size, bytes); bio_advance_iter(&rbio->bio, &bvec_iter, bytes); err: + if (ret == -BCH_ERR_data_read_retry_csum_err_maybe_userspace) + flags |= BCH_READ_must_bounce; + if (ret && !bch2_err_matches(ret, BCH_ERR_transaction_restart) && !bch2_err_matches(ret, BCH_ERR_data_read_retry)) -- 2.25.1