There is a new patch to replace this one: https://lists.freedesktop.org/archives/dri-devel/2017-October/154589.html Best regards, Jyri Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki On 10/12/17 12:39, Jyri Sarha wrote: > We are using the vrefresh to check if we are too close to vertical > sync to update the two framebuffer DMA registers and risk a > collision. The vrefresh is coming from user space and normally it is > not used for anything. For instance xserver leaves vrefresh to zero > causing a division by zero when setting the mode. We want to make sure > the value is valid and force its recalculation in > tilcdc_crtc_set_mode(). > > Reported-by: Kevin Hao <kexin.hao@xxxxxxxxxxxxx> > Fixes: 11abbc9f39e0 ("drm/tilcdc: Set framebuffer DMA address to HW only if CRTC is enabled") > Cc: <stable@xxxxxxxxxxxxxxx> # v4.11+ > Signed-off-by: Jyri Sarha <jsarha@xxxxxx> > --- > drivers/gpu/drm/tilcdc/tilcdc_crtc.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c > index 704db24..aa5e87c 100644 > --- a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c > +++ b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c > @@ -459,6 +459,16 @@ static void tilcdc_crtc_set_mode(struct drm_crtc *crtc) > drm_framebuffer_get(fb); > > crtc->hwmode = crtc->state->adjusted_mode; > + > + /* We are using the vrefresh to check if we are too close to > + * vertical sync to update the two framebuffer DMA registers > + * and risk a collision. The vrefresh is coming from user > + * space and normally it is not used for anything. We want to > + * make sure the value is valid and force its recalculation > + * here. > + */ > + crtc->hwmode.vrefresh = 0; > + crtc->hwmode.vrefresh = drm_mode_vrefresh(&crtc->hwmode); > } > > static void tilcdc_crtc_enable(struct drm_crtc *crtc) >