From: Caleb Sander Mateos <csander@purestorage.com>
Date: Tue, 6 Jan 2026 20:08:37 +0000 (-0700)
Subject: block: don't merge bios with different app_tags
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6acd4ac5f8f0ec9b946875553e52907700bcfc77;p=thirdparty%2Fkernel%2Flinux.git

block: don't merge bios with different app_tags

nvme_set_app_tag() uses the app_tag value from the bio_integrity_payload
of the struct request's first bio. This assumes all the request's bios
have the same app_tag. However, it is possible for bios with different
app_tag values to be merged into a single request.
Add a check in blk_integrity_merge_{bio,rq}() to prevent the merging of
bios/requests with different app_tag values if BIP_CHECK_APPTAG is set.

Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Fixes: 3d8b5a22d404 ("block: add support to pass user meta buffer")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/block/blk-integrity.c b/block/blk-integrity.c
index 9b27963680dc..964eebbee14d 100644
--- a/block/blk-integrity.c
+++ b/block/blk-integrity.c
@@ -140,14 +140,21 @@ EXPORT_SYMBOL_GPL(blk_rq_integrity_map_user);
 bool blk_integrity_merge_rq(struct request_queue *q, struct request *req,
 			    struct request *next)
 {
+	struct bio_integrity_payload *bip, *bip_next;
+
 	if (blk_integrity_rq(req) == 0 && blk_integrity_rq(next) == 0)
 		return true;
 
 	if (blk_integrity_rq(req) == 0 || blk_integrity_rq(next) == 0)
 		return false;
 
-	if (bio_integrity(req->bio)->bip_flags !=
-	    bio_integrity(next->bio)->bip_flags)
+	bip = bio_integrity(req->bio);
+	bip_next = bio_integrity(next->bio);
+	if (bip->bip_flags != bip_next->bip_flags)
+		return false;
+
+	if (bip->bip_flags & BIP_CHECK_APPTAG &&
+	    bip->app_tag != bip_next->app_tag)
 		return false;
 
 	if (req->nr_integrity_segments + next->nr_integrity_segments >
@@ -163,15 +170,21 @@ bool blk_integrity_merge_rq(struct request_queue *q, struct request *req,
 bool blk_integrity_merge_bio(struct request_queue *q, struct request *req,
 			     struct bio *bio)
 {
+	struct bio_integrity_payload *bip, *bip_bio = bio_integrity(bio);
 	int nr_integrity_segs;
 
-	if (blk_integrity_rq(req) == 0 && bio_integrity(bio) == NULL)
+	if (blk_integrity_rq(req) == 0 && bip_bio == NULL)
 		return true;
 
-	if (blk_integrity_rq(req) == 0 || bio_integrity(bio) == NULL)
+	if (blk_integrity_rq(req) == 0 || bip_bio == NULL)
+		return false;
+
+	bip = bio_integrity(req->bio);
+	if (bip->bip_flags != bip_bio->bip_flags)
 		return false;
 
-	if (bio_integrity(req->bio)->bip_flags != bio_integrity(bio)->bip_flags)
+	if (bip->bip_flags & BIP_CHECK_APPTAG &&
+	    bip->app_tag != bip_bio->app_tag)
 		return false;
 
 	nr_integrity_segs = blk_rq_count_integrity_sg(q, bio);