From 5baf6bb0fd2388742a0846cc7bcacee6dec78235 Mon Sep 17 00:00:00 2001 From: Marek Szyprowski Date: Thu, 14 Sep 2017 14:01:00 +0200 Subject: [PATCH] drm/exynos: Fix locking in the suspend/resume paths Commit 48a92916729b ("drm/exynos: use drm_for_each_connector_iter()") replaced unsafe drm_for_each_connector() with drm_for_each_connector_iter() and removed surrounding drm_modeset_lock calls. However, that lock was there not only to protect unsafe drm_for_each_connector(), but it was also required to be held by the dpms code which was called from the loop body. This patch restores those drm_modeset_lock calls to fix broken suspend and resume of Exynos DRM subsystem in v4.13 kernel. Fixes: 48a92916729b ("drm/exynos: use drm_for_each_connector_iter()") CC: stable@vger.kernel.org # v4.13 Signed-off-by: Marek Szyprowski Acked-by: Krzysztof Kozlowski Signed-off-by: Inki Dae --- drivers/gpu/drm/exynos/exynos_drm_drv.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.c b/drivers/gpu/drm/exynos/exynos_drm_drv.c index b1f7299..7f3cfc5 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_drv.c +++ b/drivers/gpu/drm/exynos/exynos_drm_drv.c @@ -174,6 +174,7 @@ static int exynos_drm_suspend(struct device *dev) if (pm_runtime_suspended(dev) || !drm_dev) return 0; + drm_modeset_lock_all(drm_dev); drm_connector_list_iter_begin(drm_dev, &conn_iter); drm_for_each_connector_iter(connector, &conn_iter) { int old_dpms = connector->dpms; @@ -185,6 +186,7 @@ static int exynos_drm_suspend(struct device *dev) connector->dpms = old_dpms; } drm_connector_list_iter_end(&conn_iter); + drm_modeset_unlock_all(drm_dev); return 0; } @@ -198,6 +200,7 @@ static int exynos_drm_resume(struct device *dev) if (pm_runtime_suspended(dev) || !drm_dev) return 0; + drm_modeset_lock_all(drm_dev); drm_connector_list_iter_begin(drm_dev, &conn_iter); drm_for_each_connector_iter(connector, &conn_iter) { if (connector->funcs->dpms) { @@ -208,6 +211,7 @@ static int exynos_drm_resume(struct device *dev) } } drm_connector_list_iter_end(&conn_iter); + drm_modeset_unlock_all(drm_dev); return 0; } -- 2.7.4