There is no devfreq on a3xx at the moment since gpu_busy is not
implemented. This means that msm_devfreq_init() will return early
and the entire devfreq setup is skipped.
However, msm_devfreq_active() and msm_devfreq_idle() are still called
unconditionally later, causing a NULL pointer dereference:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
Internal error: Oops: 96000004 [#1] PREEMPT SMP
CPU: 0 PID: 133 Comm: ring0 Not tainted 5.15.0-rc1 #4
Hardware name: Longcheer L8150 (DT)
pc : mutex_lock_io+0x2bc/0x2f0
lr : msm_devfreq_active+0x3c/0xe0 [msm]
Call trace:
mutex_lock_io+0x2bc/0x2f0
msm_gpu_submit+0x164/0x180 [msm]
msm_job_run+0x54/0xe0 [msm]
drm_sched_main+0x2b0/0x4a0 [gpu_sched]
kthread+0x154/0x160
ret_from_fork+0x10/0x20
Fix this by adding a check in msm_devfreq_active/idle() which ensures
that devfreq was actually initialized earlier.
Fixes: 9bc95570175a ("drm/msm: Devfreq tuning")
Reported-by: Nikita Travkin <nikita@xxxxxxx>
Tested-by: Nikita Travkin <nikita@xxxxxxx>
Signed-off-by: Stephan Gerhold <stephan@xxxxxxxxxxx>
---
drivers/gpu/drm/msm/msm_gpu_devfreq.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/msm/msm_gpu_devfreq.c b/drivers/gpu/drm/msm/msm_gpu_devfreq.c
index 0a1ee20296a2..84e98c07c900 100644
--- a/drivers/gpu/drm/msm/msm_gpu_devfreq.c
+++ b/drivers/gpu/drm/msm/msm_gpu_devfreq.c
@@ -151,6 +151,9 @@ void msm_devfreq_active(struct msm_gpu *gpu)
unsigned int idle_time;
unsigned long target_freq = df->idle_freq;
+ if (!df->devfreq)
+ return;
+
/*
* Hold devfreq lock to synchronize with get_dev_status()/
* target() callbacks
@@ -186,6 +189,9 @@ void msm_devfreq_idle(struct msm_gpu *gpu)
struct msm_gpu_devfreq *df = &gpu->devfreq;
unsigned long idle_freq, target_freq = 0;
+ if (!df->devfreq)
+ return;
+
/*
* Hold devfreq lock to synchronize with get_dev_status()/
* target() callbacks
--
2.33.0
