* drm/mediatek: fixup crtc event null pointer issue
@ 2022-03-14 7:42 Yongqiang Niu
2022-03-14 7:42 ` [PATCH v1, 1/1] " Yongqiang Niu
0 siblings, 1 reply; 6+ messages in thread
From: Yongqiang Niu @ 2022-03-14 7:42 UTC (permalink / raw)
To: Chun-Kuang Hu
Cc: devicetree, Project_Global_Chrome_Upstream_Group, David Airlie,
Jassi Brar, linux-kernel, dri-devel, Yongqiang Niu,
Dennis YC Hsieh, Fabien Parent, Rob Herring, linux-mediatek,
Hsin-Yi Wang, Matthias Brugger, linux-arm-kernel
base linux v5.17-rc1
Yongqiang Niu (1):
drm/mediatek: fixup crtc event null pointer issue
drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 3 +++
1 file changed, 3 insertions(+)
--
2.25.1
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v1, 1/1] drm/mediatek: fixup crtc event null pointer issue
2022-03-14 7:42 drm/mediatek: fixup crtc event null pointer issue Yongqiang Niu
@ 2022-03-14 7:42 ` Yongqiang Niu
2022-03-17 12:49 ` Rex-BC Chen
2022-03-28 9:34 ` CK Hu
0 siblings, 2 replies; 6+ messages in thread
From: Yongqiang Niu @ 2022-03-14 7:42 UTC (permalink / raw)
To: Chun-Kuang Hu
Cc: devicetree, Project_Global_Chrome_Upstream_Group, David Airlie,
Jassi Brar, linux-kernel, dri-devel, Yongqiang Niu,
Dennis YC Hsieh, Fabien Parent, Rob Herring, linux-mediatek,
Hsin-Yi Wang, Matthias Brugger, linux-arm-kernel
if crtc event is null pointer, do not send vblank event
Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
---
drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index d661edf7e0fe..265fed446628 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -92,6 +92,9 @@ static void mtk_drm_crtc_finish_page_flip(struct mtk_drm_crtc *mtk_crtc)
struct drm_crtc *crtc = &mtk_crtc->base;
unsigned long flags;
+ if (!mtk_crtc->event)
+ return;
+
spin_lock_irqsave(&crtc->dev->event_lock, flags);
drm_crtc_send_vblank_event(crtc, mtk_crtc->event);
drm_crtc_vblank_put(crtc);
--
2.25.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v1, 1/1] drm/mediatek: fixup crtc event null pointer issue
2022-03-14 7:42 ` [PATCH v1, 1/1] " Yongqiang Niu
@ 2022-03-17 12:49 ` Rex-BC Chen
2022-03-28 9:34 ` CK Hu
1 sibling, 0 replies; 6+ messages in thread
From: Rex-BC Chen @ 2022-03-17 12:49 UTC (permalink / raw)
To: Yongqiang Niu, Chun-Kuang Hu
Cc: devicetree, Project_Global_Chrome_Upstream_Group, David Airlie,
Jassi Brar, linux-kernel, dri-devel, Dennis YC Hsieh,
Fabien Parent, Rob Herring, linux-mediatek, Hsin-Yi Wang,
Matthias Brugger, linux-arm-kernel
On Mon, 2022-03-14 at 15:42 +0800, Yongqiang Niu wrote:
> if crtc event is null pointer, do not send vblank event
>
> Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index d661edf7e0fe..265fed446628 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -92,6 +92,9 @@ static void mtk_drm_crtc_finish_page_flip(struct
> mtk_drm_crtc *mtk_crtc)
> struct drm_crtc *crtc = &mtk_crtc->base;
> unsigned long flags;
>
> + if (!mtk_crtc->event)
> + return;
> +
Reviewed-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
> spin_lock_irqsave(&crtc->dev->event_lock, flags);
> drm_crtc_send_vblank_event(crtc, mtk_crtc->event);
> drm_crtc_vblank_put(crtc);
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v1, 1/1] drm/mediatek: fixup crtc event null pointer issue
2022-03-14 7:42 ` [PATCH v1, 1/1] " Yongqiang Niu
2022-03-17 12:49 ` Rex-BC Chen
@ 2022-03-28 9:34 ` CK Hu
2022-05-11 10:08 ` yongqiang.niu
1 sibling, 1 reply; 6+ messages in thread
From: CK Hu @ 2022-03-28 9:34 UTC (permalink / raw)
To: Yongqiang Niu, Chun-Kuang Hu
Cc: devicetree, David Airlie, Dennis YC Hsieh, Jassi Brar,
linux-kernel, dri-devel, Project_Global_Chrome_Upstream_Group,
Fabien Parent, Rob Herring, linux-mediatek, Hsin-Yi Wang,
Matthias Brugger, linux-arm-kernel
Hi, Yongqiang:
On Mon, 2022-03-14 at 15:42 +0800, Yongqiang Niu wrote:
> if crtc event is null pointer, do not send vblank event
This is a bug-fix, so add a Fixes tag here.
>
> Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index d661edf7e0fe..265fed446628 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -92,6 +92,9 @@ static void mtk_drm_crtc_finish_page_flip(struct
> mtk_drm_crtc *mtk_crtc)
> struct drm_crtc *crtc = &mtk_crtc->base;
> unsigned long flags;
>
> + if (!mtk_crtc->event)
> + return;
> +
> spin_lock_irqsave(&crtc->dev->event_lock, flags);
> drm_crtc_send_vblank_event(crtc, mtk_crtc->event);
I think pending_needs_vblank is used to protect this situation. It
seems that pending_needs_vblank should be protected by critical
section.
Regards,
CK
> drm_crtc_vblank_put(crtc);
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v1, 1/1] drm/mediatek: fixup crtc event null pointer issue
2022-03-28 9:34 ` CK Hu
@ 2022-05-11 10:08 ` yongqiang.niu
2022-05-12 5:20 ` CK Hu
0 siblings, 1 reply; 6+ messages in thread
From: yongqiang.niu @ 2022-05-11 10:08 UTC (permalink / raw)
To: CK Hu, Chun-Kuang Hu
Cc: devicetree, David Airlie, Dennis YC Hsieh, Jassi Brar,
linux-kernel, dri-devel, Project_Global_Chrome_Upstream_Group,
Fabien Parent, Rob Herring, linux-mediatek, Hsin-Yi Wang,
Matthias Brugger, linux-arm-kernel
On Mon, 2022-03-28 at 17:34 +0800, CK Hu wrote:
> Hi, Yongqiang:
>
> On Mon, 2022-03-14 at 15:42 +0800, Yongqiang Niu wrote:
> > if crtc event is null pointer, do not send vblank event
>
> This is a bug-fix, so add a Fixes tag here.
Fixes tag will be added in next version.
>
> >
> > Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
> > ---
> > drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > index d661edf7e0fe..265fed446628 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > @@ -92,6 +92,9 @@ static void mtk_drm_crtc_finish_page_flip(struct
> > mtk_drm_crtc *mtk_crtc)
> > struct drm_crtc *crtc = &mtk_crtc->base;
> > unsigned long flags;
> >
> > + if (!mtk_crtc->event)
> > + return;
> > +
> > spin_lock_irqsave(&crtc->dev->event_lock, flags);
> > drm_crtc_send_vblank_event(crtc, mtk_crtc->event);
>
> I think pending_needs_vblank is used to protect this situation. It
> seems that pending_needs_vblank should be protected by critical
> section.
>
> Regards,
> CK
actually, in the NG case pending_needs_vblank is true, but crtc->event
is null.
>
> > drm_crtc_vblank_put(crtc);
>
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v1, 1/1] drm/mediatek: fixup crtc event null pointer issue
2022-05-11 10:08 ` yongqiang.niu
@ 2022-05-12 5:20 ` CK Hu
0 siblings, 0 replies; 6+ messages in thread
From: CK Hu @ 2022-05-12 5:20 UTC (permalink / raw)
To: yongqiang.niu, Chun-Kuang Hu
Cc: devicetree, David Airlie, Dennis YC Hsieh, Jassi Brar,
linux-kernel, dri-devel, Project_Global_Chrome_Upstream_Group,
Fabien Parent, Rob Herring, linux-mediatek, Hsin-Yi Wang,
Matthias Brugger, linux-arm-kernel
Hi, Yongqiang:
On Wed, 2022-05-11 at 18:08 +0800, yongqiang.niu wrote:
> On Mon, 2022-03-28 at 17:34 +0800, CK Hu wrote:
> > Hi, Yongqiang:
> >
> > On Mon, 2022-03-14 at 15:42 +0800, Yongqiang Niu wrote:
> > > if crtc event is null pointer, do not send vblank event
> >
> > This is a bug-fix, so add a Fixes tag here.
>
> Fixes tag will be added in next version.
> >
> > >
> > > Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
> > > ---
> > > drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 3 +++
> > > 1 file changed, 3 insertions(+)
> > >
> > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > > b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > > index d661edf7e0fe..265fed446628 100644
> > > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > > @@ -92,6 +92,9 @@ static void
> > > mtk_drm_crtc_finish_page_flip(struct
> > > mtk_drm_crtc *mtk_crtc)
> > > struct drm_crtc *crtc = &mtk_crtc->base;
> > > unsigned long flags;
> > >
> > > + if (!mtk_crtc->event)
> > > + return;
> > > +
> > > spin_lock_irqsave(&crtc->dev->event_lock, flags);
> > > drm_crtc_send_vblank_event(crtc, mtk_crtc->event);
> >
> > I think pending_needs_vblank is used to protect this situation. It
> > seems that pending_needs_vblank should be protected by critical
> > section.
> >
> > Regards,
> > CK
>
> actually, in the NG case pending_needs_vblank is true, but crtc-
> >event
> is null.
It looks like that other driver access an invalid address which store
mtk_crtc->event, so mediatek drm driver has no bug and we should fix
the bug from other driver. This work around does not fix bug but just
hide the bug. So try to fix this bug in other driver.
Regards,
CK
>
> >
> > > drm_crtc_vblank_put(crtc);
> >
> >
>
>
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2022-05-12 5:21 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2022-03-14 7:42 drm/mediatek: fixup crtc event null pointer issue Yongqiang Niu
2022-03-14 7:42 ` [PATCH v1, 1/1] " Yongqiang Niu
2022-03-17 12:49 ` Rex-BC Chen
2022-03-28 9:34 ` CK Hu
2022-05-11 10:08 ` yongqiang.niu
2022-05-12 5:20 ` CK Hu
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