[lvc-project] [PATCH v2] nvme-apple: drop invalid put of admin queue reference count

[Fedor Pchelkin]

Commit 03b3bcd319b3 ("nvme: fix admin request_queue lifetime") moved the
admin queue reference ->put call into nvme_free_ctrl() - a controller
device release callback performed for every nvme driver doing
nvme_init_ctrl().

nvme-apple sets refcount of the admin queue to 1 at allocation during the
probe function and then puts it twice now:

nvme_free_ctrl()
  blk_put_queue(ctrl->admin_q) // #1
  ->free_ctrl()
    apple_nvme_free_ctrl()
      blk_put_queue(anv->ctrl.admin_q) // #2

Note that there is a commit 941f7298c70c ("nvme-apple: remove an extra
queue reference") which intended to drop taking an extra admin queue
reference.  Looks like at that moment it accidentally fixed a refcount
leak, which existed since the driver's introduction.  There were two ->get
calls at driver's probe function and a single ->put inside
apple_nvme_free_ctrl().

However now after commit 03b3bcd319b3 ("nvme: fix admin request_queue
lifetime") the refcount is imbalanced again.  Fix it by removing extra
->put call from apple_nvme_free_ctrl().  anv->dev and ctrl->dev point to
the same device, so use ctrl->dev directly for simplification.  Compile
tested only.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 03b3bcd319b3 ("nvme: fix admin request_queue lifetime")
Cc: stable at vger.kernel.org
Signed-off-by: Fedor Pchelkin <pchelkin at ispras.ru>
---

v2: use ctrl->dev directly for simplification (Jens Axboe)
link to v1: https://lore.kernel.org/linux-nvme/20260403202701.991276-1-pchelkin@ispras.ru/

 drivers/nvme/host/apple.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/nvme/host/apple.c b/drivers/nvme/host/apple.c
index ed61b97fde59..423c9c628e7b 100644
--- a/drivers/nvme/host/apple.c
+++ b/drivers/nvme/host/apple.c
@@ -1267,11 +1267,7 @@ static int apple_nvme_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
 
 static void apple_nvme_free_ctrl(struct nvme_ctrl *ctrl)
 {
-	struct apple_nvme *anv = ctrl_to_apple_nvme(ctrl);
-
-	if (anv->ctrl.admin_q)
-		blk_put_queue(anv->ctrl.admin_q);
-	put_device(anv->dev);
+	put_device(ctrl->dev);
 }
 
 static const struct nvme_ctrl_ops nvme_ctrl_ops = {
-- 
2.53.0