This is a note to let you know that I've just added the patch titled
drm/exynos: Fix locking in the suspend/resume paths
to the 4.13-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-exynos-fix-locking-in-the-suspend-resume-paths.patch
and it can be found in the queue-4.13 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 5baf6bb0fd2388742a0846cc7bcacee6dec78235 Mon Sep 17 00:00:00 2001
From: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Date: Thu, 14 Sep 2017 14:01:00 +0200
Subject: drm/exynos: Fix locking in the suspend/resume paths
From: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
commit 5baf6bb0fd2388742a0846cc7bcacee6dec78235 upstream.
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()")
Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Acked-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
Signed-off-by: Inki Dae <inki.dae@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/exynos/exynos_drm_drv.c | 4 ++++
1 file changed, 4 insertions(+)
--- a/drivers/gpu/drm/exynos/exynos_drm_drv.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_drv.c
@@ -176,6 +176,7 @@ static int exynos_drm_suspend(struct 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;
@@ -187,6 +188,7 @@ static int exynos_drm_suspend(struct dev
connector->dpms = old_dpms;
}
drm_connector_list_iter_end(&conn_iter);
+ drm_modeset_unlock_all(drm_dev);
return 0;
}
@@ -200,6 +202,7 @@ static int exynos_drm_resume(struct devi
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) {
@@ -210,6 +213,7 @@ static int exynos_drm_resume(struct devi
}
}
drm_connector_list_iter_end(&conn_iter);
+ drm_modeset_unlock_all(drm_dev);
return 0;
}
Patches currently in stable-queue which might be from m.szyprowski@xxxxxxxxxxx are
queue-4.13/drm-exynos-fix-locking-in-the-suspend-resume-paths.patch