summaryrefslogtreecommitdiffstats
path: root/drivers/md
diff options
context:
space:
mode:
authorMikulas Patocka <mpatocka@redhat.com>2022-03-28 12:34:31 -0400
committerMike Snitzer <snitzer@kernel.org>2022-04-01 13:19:27 -0400
commitaad5b23ebf21573a32b6f07644f028d64492a5d6 (patch)
tree5d8699cc392668209a04c5d69da17f91ba67fd41 /drivers/md
parentcc09e8a9dec4f0e8299e80a7a2a8e6f54164a10b (diff)
downloadlinux-aad5b23ebf21573a32b6f07644f028d64492a5d6.tar.bz2
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/md')
-rw-r--r--drivers/md/dm-core.h4
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;