Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753537AbdF0PQl (ORCPT ); Tue, 27 Jun 2017 11:16:41 -0400 Received: from mail-wm0-f67.google.com ([74.125.82.67]:33977 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752971AbdF0PBO (ORCPT ); Tue, 27 Jun 2017 11:01:14 -0400 Date: Tue, 27 Jun 2017 17:01:08 +0200 From: Daniel Vetter To: Maarten Lankhorst Cc: Harry Wentland , Andrey Grodzovsky , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, intel-gfx@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, seanpaul@chromium.org Subject: Re: [PATCH v2] drm/core: Fail atomic IOCTL with no CRTC state but with signaling. Message-ID: <20170627150108.dennwzqhmgbqmsbn@phenom.ffwll.local> Mail-Followup-To: Maarten Lankhorst , Harry Wentland , Andrey Grodzovsky , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, intel-gfx@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, seanpaul@chromium.org References: <0d603149-3fb0-3d48-89e5-77e3f7686415@amd.com> <1497981426-27203-1-git-send-email-Andrey.Grodzovsky@amd.com> <26571917-afb7-fb53-c002-5869cf8ccdf9@amd.com> <20170627073740.wz5xix2ecmvh4rbn@phenom.ffwll.local> <2fa47671-6a2b-5a19-3072-e7f59b92cb4d@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2fa47671-6a2b-5a19-3072-e7f59b92cb4d@linux.intel.com> X-Operating-System: Linux phenom 4.9.0-2-amd64 User-Agent: NeoMutt/20170306 (1.8.0) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4440 Lines: 122 On Tue, Jun 27, 2017 at 04:29:44PM +0200, Maarten Lankhorst wrote: > Op 27-06-17 om 09:37 schreef Daniel Vetter: > > On Mon, Jun 26, 2017 at 03:44:07PM -0400, Harry Wentland wrote: > >> On 2017-06-20 01:57 PM, Andrey Grodzovsky wrote: > >>> Problem : While running IGT kms_atomic_transition test suite i encountered > >>> a hang in drmHandleEvent immediately following an atomic_commit. > >>> After dumping the atomic state I relized that in this case there was > >>> not even one CRTC attached to the state and only disabled > >>> planes. This probably due to a commit which hadn't changed any property > >>> which would require attaching crtc state. This means drmHandleEvent > >>> will never wake up from read since without CRTC in atomic state > >>> the event fd will not be signaled. > >>> > >>> Fix: Protect against this issue by failing atomic_commit early in > >>> drm_mode_atomic_commit where such probelm can be identified. > >>> > >>> v2: > >>> Fix typos and extra newlines. > >>> > >>> Change-Id: I3ee28ffae35fd1e8bfe553146c44da53da02e6f8 > >>> Signed-off-by: Andrey Grodzovsky > >> Reviewed-by: Harry Wentland > > Stalling on this hoping for the igt patch. Does it exist already? > > -Daniel > > > >> Harry > >> > >>> --- > >>> drivers/gpu/drm/drm_atomic.c | 11 ++++++++++- > >>> 1 file changed, 10 insertions(+), 1 deletion(-) > >>> > >>> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > >>> index a567310..48145bf 100644 > >>> --- a/drivers/gpu/drm/drm_atomic.c > >>> +++ b/drivers/gpu/drm/drm_atomic.c > >>> @@ -1933,7 +1933,7 @@ static int prepare_crtc_signaling(struct drm_device *dev, > >>> { > >>> struct drm_crtc *crtc; > >>> struct drm_crtc_state *crtc_state; > >>> - int i, ret; > >>> + int i, c = 0, ret; > >>> > >>> if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) > >>> return 0; > >>> @@ -1994,8 +1994,17 @@ static int prepare_crtc_signaling(struct drm_device *dev, > >>> > >>> crtc_state->event->base.fence = fence; > >>> } > >>> + > >>> + c++; > >>> } > >>> > >>> + /* > >>> + * Having this flag means user mode pends on event which will never > >>> + * reach due to lack of at least one CRTC for signaling > >>> + */ > >>> + if (c == 0 && (arg->flags & DRM_MODE_PAGE_FLIP_EVENT)) > >>> + return -EINVAL; > >>> + > >>> return 0; > >>> } > >>> > >>> > Just do it, and I'll commit this to igt? Ack on both the kernel patch and the igt patch, feel free to push them both with: Acked-by: Daniel Vetter If you do, please add the Testcase: line to the kernel patch. Thanks, Daniel > > diff --git a/tests/kms_atomic.c b/tests/kms_atomic.c > index 6375fede7179..77429b3db384 100644 > --- a/tests/kms_atomic.c > +++ b/tests/kms_atomic.c > @@ -1205,6 +1205,15 @@ static void crtc_invalid_params(struct kms_atomic_crtc_state *crtc_old, > crtc_commit_atomic(&crtc, plane, req, ATOMIC_RELAX_NONE, > DRM_MODE_ATOMIC_TEST_ONLY); > > + /* > + * TEST_ONLY cannot be combined with DRM_MODE_PAGE_FLIP_EVENT, > + * but DRM_MODE_PAGE_FLIP_EVENT will always generate EINVAL > + * without valid crtc, so test it here. > + */ > + crtc_commit_atomic_err(&crtc, plane, req, ATOMIC_RELAX_NONE, > + DRM_MODE_ATOMIC_TEST_ONLY | DRM_MODE_PAGE_FLIP_EVENT, > + EINVAL); > + > /* Create a blob which is the wrong size to be a valid mode. */ > do_or_die(drmModeCreatePropertyBlob(crtc.state->desc->fd, > crtc.mode.data, > @@ -1356,12 +1365,12 @@ static void atomic_invalid_params(struct kms_atomic_crtc_state *crtc, > /* Valid pointers, but still should copy nothing. */ > do_ioctl(desc->fd, DRM_IOCTL_MODE_ATOMIC, &ioc); > > - /* Nonsense flags. */ > - ioc.flags = 0xdeadbeef; > + /* Valid noop, but with event set should fail. */ > + ioc.flags = DRM_MODE_PAGE_FLIP_EVENT; > do_ioctl_err(desc->fd, DRM_IOCTL_MODE_ATOMIC, &ioc, EINVAL); > > - /* Specifically forbidden combination. */ > - ioc.flags = DRM_MODE_ATOMIC_TEST_ONLY | DRM_MODE_PAGE_FLIP_EVENT; > + /* Nonsense flags. */ > + ioc.flags = 0xdeadbeef; > do_ioctl_err(desc->fd, DRM_IOCTL_MODE_ATOMIC, &ioc, EINVAL); > > ioc.flags = 0; > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch