On Wed, Nov 8, 2023 at 3:27 PM CK Hu (胡俊光) <ck.hu@xxxxxxxxxxxx> wrote: > > Hi, Jason: > > On Wed, 2023-09-20 at 17:06 +0800, Jason-JH.Lin wrote: > > Add spinlock protection to avoid race condition on vblank event > > between mtk_drm_crtc_atomic_begin() and mtk_drm_finish_page_flip(). > > Reviewed-by: CK Hu <ck.hu@xxxxxxxxxxxx> Please also merge this for fixes so it lands sooner. > > > > Fixes: 119f5173628a ("drm/mediatek: Add DRM Driver for Mediatek SoC > > MT8173.") > > Signed-off-by: Jason-JH.Lin <jason-jh.lin@xxxxxxxxxxxx> > > Suggested-by: AngeloGioacchino Del Regno < > > angelogioacchino.delregno@xxxxxxxxxxxxx> > > Reviewed-by: Alexandre Mergnat <amergnat@xxxxxxxxxxxx> > > Reviewed-by: Fei Shao <fshao@xxxxxxxxxxxx> > > Tested-by: Fei Shao <fshao@xxxxxxxxxxxx> > > --- > > drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c > > b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c > > index b6fa4ad2f94d..cab4fe092f13 100644 > > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c > > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c > > @@ -744,6 +744,7 @@ static void mtk_drm_crtc_atomic_begin(struct > > drm_crtc *crtc, > > > > crtc); > > struct mtk_crtc_state *mtk_crtc_state = > > to_mtk_crtc_state(crtc_state); > > struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc); > > + unsigned long flags; > > > > if (mtk_crtc->event && mtk_crtc_state->base.event) > > DRM_ERROR("new event while there is still a pending > > event\n"); > > @@ -751,7 +752,11 @@ static void mtk_drm_crtc_atomic_begin(struct > > drm_crtc *crtc, > > if (mtk_crtc_state->base.event) { > > mtk_crtc_state->base.event->pipe = > > drm_crtc_index(crtc); > > WARN_ON(drm_crtc_vblank_get(crtc) != 0); > > + > > + spin_lock_irqsave(&crtc->dev->event_lock, flags); > > mtk_crtc->event = mtk_crtc_state->base.event; > > + spin_unlock_irqrestore(&crtc->dev->event_lock, flags); > > + > > mtk_crtc_state->base.event = NULL; > > } > > }