[PATCH] drm/atomic: Check that the config funcs exist drm_mode_alloc

From: Jordan Crouse <jcrouse@codeaurora.org>
To: freedreno@lists.freedesktop.org
Cc: linux-arm-msm@vger.kernel.org, Sean Paul <sean@poorly.run>,
	linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
	David Airlie <airlied@linux.ie>,
	Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
	Maxime Ripard <maxime.ripard@bootlin.com>,
	Daniel Vetter <daniel@ffwll.ch>
Subject: [PATCH] drm/atomic: Check that the config funcs exist drm_mode_alloc
Date: Tue,  7 May 2019 13:14:11 -0600	[thread overview]
Message-ID: <1557256451-24950-1-git-send-email-jcrouse@codeaurora.org> (raw)

An error while initializing the msm driver ends up calling
drm_atomic_helper_shutdown() without first initializing the funcs
in mode_config. While I'm not 100% sure this isn't a ordering
problem in msm adding a check to drm_mode_alloc seems like
a nice and safe solution.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
---

 drivers/gpu/drm/drm_atomic.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 5eb4013..1729428 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -114,6 +114,9 @@ drm_atomic_state_alloc(struct drm_device *dev)
 {
 	struct drm_mode_config *config = &dev->mode_config;
 
+	if (!config->funcs)
+		return NULL;
+
 	if (!config->funcs->atomic_state_alloc) {
 		struct drm_atomic_state *state;
 
-- 
2.7.4
