block: check if a profile is actually registered in blk_integrity_unregister

While clearing the profile itself is harmless, we really should not clear
the stable writes flag if it wasn't set due to a registered integrity
profile.

Reported-by: Lihong Kou <koulihong@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Link: https://lore.kernel.org/r/20210914070657.87677-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-integrity.c b/block/blk-integrity.c
index 69a12177dfb62f6d1f1fc3f1f1166ca52cceae5c..48bfb53aa85714a7fa31c014f80932ffe042725c 100644 (file)
--- a/block/blk-integrity.c
+++ b/block/blk-integrity.c
@@ -426,8 +426,12 @@ EXPORT_SYMBOL(blk_integrity_register);
  */
 void blk_integrity_unregister(struct gendisk *disk)
 {
+       struct blk_integrity *bi = &disk->queue->integrity;
+
+       if (!bi->profile)
+               return;
        blk_queue_flag_clear(QUEUE_FLAG_STABLE_WRITES, disk->queue);
-       memset(&disk->queue->integrity, 0, sizeof(struct blk_integrity));
+       memset(bi, 0, sizeof(*bi));
 }
 EXPORT_SYMBOL(blk_integrity_unregister);