From: Douglas Anderson <dianders@chromium.org> stable inclusion from stable-5.10.50 commit 0cd39c96574d19e234cee971868c82c3769c2ee6 bugzilla: 174522 https://gitee.com/openeuler/kernel/issues/I4DNFY Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit bab5cca7e609952b069a550e39fe4893149fb658 ] The drm_bridge_chain_pre_enable() is not the proper opposite of drm_bridge_chain_post_disable(). It continues along the chain to _before_ the starting bridge. Let's fix that. Fixes: 05193dc38197 ("drm/bridge: Make the bridge chain a double-linked list") Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Andrzej Hajda <a.hajda@samsung.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210416153909.v4.1.If62a003f7... Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- drivers/gpu/drm/drm_bridge.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index 64f0effb52ac..044acd07c153 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -522,6 +522,9 @@ void drm_bridge_chain_pre_enable(struct drm_bridge *bridge) list_for_each_entry_reverse(iter, &encoder->bridge_chain, chain_node) { if (iter->funcs->pre_enable) iter->funcs->pre_enable(iter); + + if (iter == bridge) + break; } } EXPORT_SYMBOL(drm_bridge_chain_pre_enable); -- 2.20.1