Linux-ARM-Kernel Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: Guangshuo Li <lgs201920130244@gmail.com>
To: "Mauro Carvalho Chehab" <mchehab@kernel.org>,
	"Matthias Brugger" <matthias.bgg@gmail.com>,
	"AngeloGioacchino Del Regno"
	<angelogioacchino.delregno@collabora.com>,
	"Hans Verkuil" <hverkuil+cisco@kernel.org>,
	"Nicolas Dufresne" <nicolas.dufresne@collabora.com>,
	"Guangshuo Li" <lgs201920130244@gmail.com>,
	"Johan Hovold" <johan@kernel.org>,
	"Marco Crivellari" <marco.crivellari@suse.com>,
	"Thomas Weißschuh" <thomas.weissschuh@linutronix.de>,
	"Kees Cook" <kees@kernel.org>,
	linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-mediatek@lists.infradead.org
Subject: [PATCH] media: platform: mtk-mdp3: Fix SCP device refcounting
Date: Sun,  5 Jul 2026 01:31:19 +0800	[thread overview]
Message-ID: <20260704173119.254975-1-lgs201920130244@gmail.com> (raw)

mdp_probe() first tries to get the SCP handle with scp_get(). When that
fails, it falls back to looking up the SCP platform device with
__get_pdev_by_id() and then reads its driver data.

The fallback lookup returns the platform device with a reference, just
like scp_get() does. However, the fallback path currently drops that
reference immediately after platform_get_drvdata(). The driver later
still calls scp_put(mdp->scp) unconditionally from the probe error path
and from mdp_video_device_release(), which drops the SCP device
reference again.

Keep the fallback reference until the existing scp_put() call, so that
the fallback path follows the same ownership rules as the scp_get()
path.

Fixes: 8f6f3aa21517 ("media: platform: mtk-mdp3: fix device leaks at probe")
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
---
 drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c b/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c
index 8f4da4cf55d2..121b1006ffdc 100644
--- a/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c
+++ b/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c
@@ -294,7 +294,6 @@ static int mdp_probe(struct platform_device *pdev)
 			goto err_destroy_clock_wq;
 		}
 		mdp->scp = platform_get_drvdata(mm_pdev);
-		put_device(&mm_pdev->dev);
 	}
 
 	mdp->rproc_handle = scp_get_rproc(mdp->scp);
-- 
2.43.0



             reply	other threads:[~2026-07-04 17:31 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-04 17:31 Guangshuo Li [this message]
2026-07-06  6:50 ` [PATCH] media: platform: mtk-mdp3: Fix SCP device refcounting Johan Hovold

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260704173119.254975-1-lgs201920130244@gmail.com \
    --to=lgs201920130244@gmail.com \
    --cc=angelogioacchino.delregno@collabora.com \
    --cc=hverkuil+cisco@kernel.org \
    --cc=johan@kernel.org \
    --cc=kees@kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=linux-mediatek@lists.infradead.org \
    --cc=marco.crivellari@suse.com \
    --cc=matthias.bgg@gmail.com \
    --cc=mchehab@kernel.org \
    --cc=nicolas.dufresne@collabora.com \
    --cc=thomas.weissschuh@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox