diff options
| author | Mikulas Patocka <mpatocka@redhat.com> | 2022-03-28 12:34:31 -0400 |
|---|---|---|
| committer | Mike Snitzer <snitzer@kernel.org> | 2022-04-01 13:19:27 -0400 |
| commit | aad5b23ebf21573a32b6f07644f028d64492a5d6 (patch) | |
| tree | 5d8699cc392668209a04c5d69da17f91ba67fd41 /drivers | |
| parent | cc09e8a9dec4f0e8299e80a7a2a8e6f54164a10b (diff) | |
dm: fix dm_io and dm_target_io flags race condition on Alpha
Early alpha processors cannot write a single byte or short; they read 8
bytes, modify the value in registers and write back 8 bytes.
This could cause race condition in the structure dm_io - if the fields
flags and io_count are modified simultaneously.
Fix this bug by using 32-bit flags if we are on Alpha and if we are
compiling for a processor that doesn't have the byte-word-extension.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: bd4a6dd241ae ("dm: reduce size of dm_io and dm_target_io structs")
[snitzer: Jens allowed this change since Mikulas owns a relevant Alpha!]
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/md/dm-core.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h index 4081cb6cf7b3..4277853c7535 100644 --- a/drivers/md/dm-core.h +++ b/drivers/md/dm-core.h @@ -210,7 +210,7 @@ struct dm_table { #define DM_TIO_MAGIC 28714 struct dm_target_io { unsigned short magic; - unsigned short flags; + blk_short_t flags; unsigned int target_bio_nr; struct dm_io *io; struct dm_target *ti; @@ -244,7 +244,7 @@ static inline void dm_tio_set_flag(struct dm_target_io *tio, unsigned int bit) #define DM_IO_MAGIC 19577 struct dm_io { unsigned short magic; - unsigned short flags; + blk_short_t flags; atomic_t io_count; struct mapped_device *md; struct bio *orig_bio; |