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 <[email protected]>
---
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 c2ea978c8921..21e271a318ee 100644
--- a/drivers/gpu/drm/msm/msm_gpu_devfreq.c
+++ b/drivers/gpu/drm/msm/msm_gpu_devfreq.c
@@ -198,6 +198,8 @@ 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
On Fri, Jul 8, 2022 at 9:24 AM Bjorn Andersson
<[email protected]> wrote:
>
> 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 <[email protected]>
Reviewed-by: Rob Clark <[email protected]>
> ---
> 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 c2ea978c8921..21e271a318ee 100644
> --- a/drivers/gpu/drm/msm/msm_gpu_devfreq.c
> +++ b/drivers/gpu/drm/msm/msm_gpu_devfreq.c
> @@ -198,6 +198,8 @@ 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
>
On 08/07/2022 19:26, Bjorn Andersson wrote:
> 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 <[email protected]>
Reviewed-by: Dmitry Baryshkov <[email protected]>
> ---
> drivers/gpu/drm/msm/msm_gpu_devfreq.c | 2 ++
> 1 file changed, 2 insertions(+)
--
With best wishes
Dmitry