4.18-stable review patch. If anyone has any objections, please let me know.
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From: Mikulas Patocka mpatocka@redhat.com
commit 8b2ded1c94c06f841f8c1612bcfa33c85012a36b upstream.
It is possible to call fsync on a read-only handle (for example, fsck.ext2 does it when doing read-only check), and this call results in kernel warning.
The patch b089cfd95d32 ("block: don't warn for flush on read-only device") attempted to disable the warning, but it is buggy and it doesn't (op_is_flush tests flags, but bio_op strips off the flags).
Signed-off-by: Mikulas Patocka mpatocka@redhat.com Fixes: 721c7fc701c7 ("block: fail op_is_write() requests to read-only partitions") Cc: stable@vger.kernel.org # 4.18 Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- block/blk-core.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
--- a/block/blk-core.c +++ b/block/blk-core.c @@ -2161,9 +2161,12 @@ static inline bool bio_check_ro(struct b { const int op = bio_op(bio);
- if (part->policy && (op_is_write(op) && !op_is_flush(op))) { + if (part->policy && op_is_write(op)) { char b[BDEVNAME_SIZE];
+ if (op_is_flush(bio->bi_opf) && !bio_sectors(bio)) + return false; + WARN_ONCE(1, "generic_make_request: Trying to write " "to read-only block-device %s (partno %d)\n",