[PATCH 5.19 010/155] drm/msm/gpu: Drop qos request if devm_devfreq_add_device() fails

From: Greg Kroah-Hartman
Date: Tue Sep 06 2022 - 10:01:10 EST


From: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>

[ Upstream commit 02b9f2636209beb843ca501d47f7fddc8792b2d7 ]

In the event that devm_devfreq_add_device() fails the device's qos freq
list is left referencing df->idle_freq and df->boost_freq. Attempting to
initialize devfreq again after a probe deferral will then cause invalid
memory accesses in dev_pm_qos_add_request().

Fix this by dropping the requests in the error path.

Fixes: 7c0ffcd40b16 ("drm/msm/gpu: Respect PM QoS constraints")
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Reviewed-by: Rob Clark <robdclark@xxxxxxxxx>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Patchwork: https://patchwork.freedesktop.org/patch/493001/
Link: https://lore.kernel.org/r/20220708162632.3529864-1-bjorn.andersson@xxxxxxxxxx
Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/msm/msm_gpu_devfreq.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/msm/msm_gpu_devfreq.c b/drivers/gpu/drm/msm/msm_gpu_devfreq.c
index ea94bc18e72eb..89cc93eb67557 100644
--- a/drivers/gpu/drm/msm/msm_gpu_devfreq.c
+++ b/drivers/gpu/drm/msm/msm_gpu_devfreq.c
@@ -213,6 +213,8 @@ void msm_devfreq_init(struct msm_gpu *gpu)

if (IS_ERR(df->devfreq)) {
DRM_DEV_ERROR(&gpu->pdev->dev, "Couldn't initialize GPU devfreq\n");
+ dev_pm_qos_remove_request(&df->idle_freq);
+ dev_pm_qos_remove_request(&df->boost_freq);
df->devfreq = NULL;
return;
}
--
2.35.1