On Sat, Apr 20, 2024 at 04:02:00PM -0700, Abhinav Kumar wrote: > > > On 4/19/2024 7:33 PM, Dmitry Baryshkov wrote: > > MSM display drivers provide kms structure allocated during probe(). > > Don't clean up priv->kms field in case of an error. Otherwise probe > > functions might fail after KMS probe deferral. > > > > So just to understand this more, this will happen when master component > probe (dpu) succeeded but other sub-component probe (dsi) deferred? > > Because if master component probe itself deferred it will allocate priv->kms > again isnt it and we will not even hit here.
Master probing succeeds (so priv->kms is set), then kms_init fails at runtime, during binding of the master device. This results in probe deferral from the last component's component_add() function and reprobe attempt when possible (once the next device is added or probed). However as priv->kms is NULL, probe crashes. > > > Fixes: a2ab5d5bb6b1 ("drm/msm: allow passing struct msm_kms to > > msm_drv_probe()") > > Signed-off-by: Dmitry Baryshkov <dmitry.barysh...@linaro.org> > > --- > > drivers/gpu/drm/msm/msm_kms.c | 1 - > > 1 file changed, 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/msm/msm_kms.c b/drivers/gpu/drm/msm/msm_kms.c > > index af6a6fcb1173..6749f0fbca96 100644 > > --- a/drivers/gpu/drm/msm/msm_kms.c > > +++ b/drivers/gpu/drm/msm/msm_kms.c > > @@ -244,7 +244,6 @@ int msm_drm_kms_init(struct device *dev, const struct > > drm_driver *drv) > > ret = priv->kms_init(ddev); > > if (ret) { > > DRM_DEV_ERROR(dev, "failed to load kms\n"); > > - priv->kms = NULL; > > return ret; > > } > > -- With best wishes Dmitry