[PATCH 4.18 055/145] dm integrity: change suspending variable from bool to int

From: Greg Kroah-Hartman
Date: Fri Sep 07 2018 - 17:15:04 EST


4.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Mikulas Patocka <mpatocka@xxxxxxxxxx>

commit c21b16392701543d61e366dca84e15fe7f0cf0cf upstream.

Early alpha processors can't write a byte or short atomically - they
read 8 bytes, modify the byte or two bytes in registers and write back
8 bytes.

The modification of the variable "suspending" may race with
modification of the variable "failed". Fix this by changing
"suspending" to an int.

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/md/dm-integrity.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -178,7 +178,7 @@ struct dm_integrity_c {
__u8 sectors_per_block;

unsigned char mode;
- bool suspending;
+ int suspending;

int failed;

@@ -2210,7 +2210,7 @@ static void dm_integrity_postsuspend(str

del_timer_sync(&ic->autocommit_timer);

- ic->suspending = true;
+ WRITE_ONCE(ic->suspending, 1);

queue_work(ic->commit_wq, &ic->commit_work);
drain_workqueue(ic->commit_wq);
@@ -2220,7 +2220,7 @@ static void dm_integrity_postsuspend(str
dm_integrity_flush_buffers(ic);
}

- ic->suspending = false;
+ WRITE_ONCE(ic->suspending, 0);

BUG_ON(!RB_EMPTY_ROOT(&ic->in_progress));