komeda_platform_probe() enables runtime PM before publishing the driver
data. The runtime PM callbacks dereference the driver data, so a
callback running in that window dereferences NULL.
The debugfs register file is created while komeda_dev_create() runs and
its read path calls pm_runtime_get_sync(). The DRM minor is registered
before dev_set_drvdata() as well. Either path can invoke
komeda_rt_pm_resume() while the driver data is still NULL.
Publish mdrv immediately after komeda_dev_create() succeeds and before
enabling runtime PM. This guarantees that runtime PM callbacks always
see a fully initialized mdrv->mdev.
Fixes: efb465088518 ("drm/komeda: Add runtime_pm support")
Signed-off-by: Jiale Yao <[email protected]>
---
drivers/gpu/drm/arm/display/komeda/komeda_drv.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_drv.c
b/drivers/gpu/drm/arm/display/komeda/komeda_drv.c
index 67fffab018ae..82efa74199be 100644
--- a/drivers/gpu/drm/arm/display/komeda/komeda_drv.c
+++ b/drivers/gpu/drm/arm/display/komeda/komeda_drv.c
@@ -73,6 +73,8 @@ static int komeda_platform_probe(struct platform_device *pdev)
goto free_mdrv;
}
+ dev_set_drvdata(dev, mdrv);
+
pm_runtime_enable(dev);
if (!pm_runtime_enabled(dev)) {
err = komeda_dev_resume(mdrv->mdev);
@@ -86,7 +88,6 @@ static int komeda_platform_probe(struct platform_device *pdev)
goto destroy_mdev;
}
- dev_set_drvdata(dev, mdrv);
drm_client_setup(&mdrv->kms->base, NULL);
return 0;
--
2.34.1
