[PATCH] drm/msm: fix possible oops in msm_submitqueues code

From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
To: Bjorn Andersson <bjorn.andersson@linaro.org>,
	Rob Clark <robdclark@gmail.com>, Sean Paul <sean@poorly.run>,
	Abhinav Kumar <abhinavk@codeaurora.org>
Cc: Jonathan Marek <jonathan@marek.ca>,
	Stephen Boyd <sboyd@kernel.org>, David Airlie <airlied@linux.ie>,
	Daniel Vetter <daniel@ffwll.ch>,
	linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org,
	freedreno@lists.freedesktop.org
Subject: [PATCH] drm/msm: fix possible oops in msm_submitqueues code
Date: Sat, 25 Sep 2021 22:27:54 +0300	[thread overview]
Message-ID: <20210925192754.3416212-1-dmitry.baryshkov@linaro.org> (raw)

Even without GPU, the ctx->submitqueues list should be properly
initialized. Otherwise msm_submitqueue_close() (which can still be
called even w/o the GPU) will ooops while trying to traverse the list.

Move ctx->submitqueues initialization earlier, before !GPU check.

Fixes: 86c2a0f000c1 ("drm/msm: Small submitqueue creation cleanup")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/msm/msm_submitqueue.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_submitqueue.c b/drivers/gpu/drm/msm/msm_submitqueue.c
index 32a55d81b58b..a0303be05445 100644
--- a/drivers/gpu/drm/msm/msm_submitqueue.c
+++ b/drivers/gpu/drm/msm/msm_submitqueue.c
@@ -128,6 +128,8 @@ int msm_submitqueue_init(struct drm_device *drm, struct msm_file_private *ctx)
 	struct msm_drm_private *priv = drm->dev_private;
 	int default_prio, max_priority;
 
+	INIT_LIST_HEAD(&ctx->submitqueues);
+
 	if (!priv->gpu)
 		return -ENODEV;
 
@@ -140,8 +142,6 @@ int msm_submitqueue_init(struct drm_device *drm, struct msm_file_private *ctx)
 	 */
 	default_prio = DIV_ROUND_UP(max_priority, 2);
 
-	INIT_LIST_HEAD(&ctx->submitqueues);
-
 	rwlock_init(&ctx->queuelock);
 
 	return msm_submitqueue_create(drm, ctx, default_prio, 0, NULL);
-- 
2.33.0

