| Message ID | 20190802083901.2018-1-peter.ujfalusi@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/tilcdc: Check priv->crtc validity in cpufreq_transition() | expand |
On 02/08/2019 11:39, Peter Ujfalusi wrote: > The notifier can be called before we have crtc. With the check we can avoid > NULL pointer dereference within tilcdc_crtc_update_clk(). > > Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Peter, do you have "drm/tilcdc: Register cpufreq notifier after we have initialized crtc" [1] in your branch? It was merged in v5.0. If you do and still see the crash, then I need to study this more. Best regards, Jyri [1] https://patchwork.freedesktop.org/patch/292412/ commit 432973fd3a20102840d5f7e61af9f1a03c217a4c > --- > drivers/gpu/drm/tilcdc/tilcdc_drv.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.c b/drivers/gpu/drm/tilcdc/tilcdc_drv.c > index 3046a4a4232d..85093123722d 100644 > --- a/drivers/gpu/drm/tilcdc/tilcdc_drv.c > +++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.c > @@ -169,7 +169,7 @@ static int cpufreq_transition(struct notifier_block *nb, > struct tilcdc_drm_private *priv = container_of(nb, > struct tilcdc_drm_private, freq_transition); > > - if (val == CPUFREQ_POSTCHANGE) > + if (val == CPUFREQ_POSTCHANGE && priv->crtc) > tilcdc_crtc_update_clk(priv->crtc); > > return 0; >
On 02/08/2019 12.35, Jyri Sarha wrote: > On 02/08/2019 11:39, Peter Ujfalusi wrote: >> The notifier can be called before we have crtc. With the check we can avoid >> NULL pointer dereference within tilcdc_crtc_update_clk(). >> >> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> > > Peter, do you have "drm/tilcdc: Register cpufreq notifier after we have > initialized crtc" [1] in your branch? It was merged in v5.0. If you do > and still see the crash, then I need to study this more. > > Best regards, > Jyri > > [1] https://patchwork.freedesktop.org/patch/292412/ > commit 432973fd3a20102840d5f7e61af9f1a03c217a4c Your patch fixed the issue in a better way. I was just carrying this since December 2018 and since it still applies I thought that I will send it... Just ignore this patch and thanks for the proper fix. > >> --- >> drivers/gpu/drm/tilcdc/tilcdc_drv.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.c b/drivers/gpu/drm/tilcdc/tilcdc_drv.c >> index 3046a4a4232d..85093123722d 100644 >> --- a/drivers/gpu/drm/tilcdc/tilcdc_drv.c >> +++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.c >> @@ -169,7 +169,7 @@ static int cpufreq_transition(struct notifier_block *nb, >> struct tilcdc_drm_private *priv = container_of(nb, >> struct tilcdc_drm_private, freq_transition); >> >> - if (val == CPUFREQ_POSTCHANGE) >> + if (val == CPUFREQ_POSTCHANGE && priv->crtc) >> tilcdc_crtc_update_clk(priv->crtc); >> >> return 0; >> > > - Péter Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.c b/drivers/gpu/drm/tilcdc/tilcdc_drv.c index 3046a4a4232d..85093123722d 100644 --- a/drivers/gpu/drm/tilcdc/tilcdc_drv.c +++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.c @@ -169,7 +169,7 @@ static int cpufreq_transition(struct notifier_block *nb, struct tilcdc_drm_private *priv = container_of(nb, struct tilcdc_drm_private, freq_transition); - if (val == CPUFREQ_POSTCHANGE) + if (val == CPUFREQ_POSTCHANGE && priv->crtc) tilcdc_crtc_update_clk(priv->crtc); return 0;
The notifier can be called before we have crtc. With the check we can avoid NULL pointer dereference within tilcdc_crtc_update_clk(). Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> --- drivers/gpu/drm/tilcdc/tilcdc_drv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)