Remove the line in dispatch_bh() that sets bh->b_dev to B_FREE, since it sets bh->b_dev to job->disk.dev a few lines later. --- linux-2.4.20a/drivers/md/kcopyd.c 2003/01/09 16:14:52 +++ linux-2.4.20b/drivers/md/kcopyd.c 2003/01/09 16:38:13 @@ -330,7 +330,6 @@ p = block >> job->bpp_shift; block &= job->bpp_mask; - bh->b_dev = B_FREE; bh->b_size = job->block_size; set_bh_page(bh, job->pages[p], ((block << job->block_shift) + job->offset) << SECTOR_SHIFT);