Hi, On Thu, Oct 08, 2015 at 01:50:21PM -0700, Wayne Boyer wrote: > From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > > A long time ago (before 3.14) we relied on a permanent pinning of the > ifbdev to lock the fb in place inside the GGTT. However, the > introduction of stealing the BIOS framebuffer and reusing its address in > the GGTT for the fbdev has muddied waters and we use an inherited fb. > However, the inherited fb is only pinned whilst it is active and we no > longer have an explicit pin for the info->system_base mmapping used by > the fbdev. The result is that after some aperture pressure the fbdev may > be evicted, but we continue to write the fbcon into the same GGTT > address - overwriting anything else that may be put into that offset. > The effect is most pronounced across suspend/resume as > intel_fbdev_set_suspend() does a full clear over the whole scanout. > > v2: rebased on latest nightly (Wayne) > v3: changed i915_gem_object_ggtt_pin() to i915_gem_obj_ggtt_pin() based > on Chris' review. (Wayne) > > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Cc: "Goel, Akash" <akash.goel@xxxxxxxxx> > Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> > Cc: Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx > Reviewed-by: Deepak S <deepak.s@xxxxxxxxxxxxxxx> > Signed-off-by: Wayne Boyer <wayne.boyer@xxxxxxxxx> > --- > drivers/gpu/drm/i915/intel_fbdev.c | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/drivers/gpu/drm/i915/intel_fbdev.c b/drivers/gpu/drm/i915/intel_fbdev.c > index 6532912..0ad46521 100644 > --- a/drivers/gpu/drm/i915/intel_fbdev.c > +++ b/drivers/gpu/drm/i915/intel_fbdev.c > @@ -215,6 +215,16 @@ static int intelfb_create(struct drm_fb_helper *helper, > obj = intel_fb->obj; > size = obj->base.size; > > + /* The fb constructor will have already pinned us (or inherited a > + * GGTT region from the BIOS) suitable for a scanout, so > + * this should just be a no-op and increment the pin count for the > + * fbdev mmapping. It does have a useful side-effect of validating > + * the pin for fbdev's use via a GGTT mmapping. > + */ > + ret = i915_gem_obj_ggtt_pin(obj, 0, PIN_MAPPABLE); > + if (ret) > + goto out_unlock; I think a DRM_ERROR() should be added here, otherwise if this check fails, the user will never be notified thereof. It's not sufficient to just return a negative int because this just gets passed up the call stack to intel_fbdev_initial_config() which ignores it. I'm adding DRM_ERROR() invocations to the two existing error conditions in this function with patch 4 of the series I just posted to intel-gfx: Link: http://lists.freedesktop.org/archives/intel-gfx/2015-October/078837.html Message-Id: <e08c113c04191ecd66904423da4f1908f48b5ef6.1445771693.git.lukas@xxxxxxxxx> Best regards, Lukas > + > info = drm_fb_helper_alloc_fbi(helper); > if (IS_ERR(info)) { > ret = PTR_ERR(info); > @@ -274,6 +284,9 @@ static int intelfb_create(struct drm_fb_helper *helper, > out_destroy_fbi: > drm_fb_helper_release_fbi(helper); > out_unpin: > + /* Once for info->screen_base mmaping... */ > + i915_gem_object_ggtt_unpin(obj); > + /* ...and once for the intel_fb */ > i915_gem_object_ggtt_unpin(obj); > drm_gem_object_unreference(&obj->base); > out_unlock: > @@ -514,6 +527,8 @@ static const struct drm_fb_helper_funcs intel_fb_helper_funcs = { > static void intel_fbdev_destroy(struct drm_device *dev, > struct intel_fbdev *ifbdev) > { > + /* Release the pinning for the info->screen_base mmaping. */ > + i915_gem_object_ggtt_unpin(ifbdev->fb->obj); > > drm_fb_helper_unregister_fbi(&ifbdev->helper); > drm_fb_helper_release_fbi(&ifbdev->helper); > -- > 1.9.1 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html