4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jens Axboe <axboe@xxxxxxxxx> [ Upstream commit b089cfd95d32638335c551651a8e00fd2c4edb0b ] Don't warn for a flush issued to a read-only device. It's not strictly a writable command, as it doesn't change any on-media data by itself. Reported-by: Stefan Agner <stefan@xxxxxxxx> Fixes: 721c7fc701c7 ("block: fail op_is_write() requests to read-only partitions") Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- block/blk-core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/block/blk-core.c +++ b/block/blk-core.c @@ -2159,7 +2159,9 @@ static inline bool should_fail_request(s static inline bool bio_check_ro(struct bio *bio, struct hd_struct *part) { - if (part->policy && op_is_write(bio_op(bio))) { + const int op = bio_op(bio); + + if (part->policy && (op_is_write(op) && !op_is_flush(op))) { char b[BDEVNAME_SIZE]; WARN_ONCE(1,