4.9-stable patches

[thirdparty/kernel/stable-queue.git] / releases / 4.14.69 / dm-integrity-change-suspending-variable-from-bool-to-int.patch

From c21b16392701543d61e366dca84e15fe7f0cf0cf Mon Sep 17 00:00:00 2001
From: Mikulas Patocka <mpatocka@redhat.com>
Date: Tue, 3 Jul 2018 20:13:25 +0200
Subject: dm integrity: change 'suspending' variable from bool to int

From: Mikulas Patocka <mpatocka@redhat.com>

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@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 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
@@ -177,7 +177,7 @@ struct dm_integrity_c {
 	__u8 sectors_per_block;
 
 	unsigned char mode;
-	bool suspending;
+	int suspending;
 
 	int failed;
 
@@ -2209,7 +2209,7 @@ 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);
@@ -2219,7 +2219,7 @@ 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));