From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 41DE0C433E6 for ; Fri, 5 Feb 2021 17:49:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DE67864DE7 for ; Fri, 5 Feb 2021 17:49:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232144AbhBEQHV (ORCPT ); Fri, 5 Feb 2021 11:07:21 -0500 Received: from mail.kernel.org ([198.145.29.99]:53906 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233497AbhBEQBY (ORCPT ); Fri, 5 Feb 2021 11:01:24 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 317D46506C; Fri, 5 Feb 2021 14:12:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1612534374; bh=uwFvfc6L4wpnKmbVy14n1pGZETZp9bDsqif3aF84e58=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=b977jaWgUz0ek9I20QieC5A0NmM7dJEo+HtCez2Y3v5iysueVRTupKrd2ltKQSsBq JoRlDoT3It4E41t+Y+Jh4JhZno6hn5hOnunU6n/dUWyl/XAvTuy8vQuqLTAnVOfd1V yYaLN7PAc6GTd7FQqEfk4sHg1FtZyhgqtH1DWOyo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Wheeler , Bing Guo , Jun Lei , Anson Jacob , Alex Deucher , Sasha Levin Subject: [PATCH 5.4 29/32] drm/amd/display: Change function decide_dp_link_settings to avoid infinite looping Date: Fri, 5 Feb 2021 15:07:44 +0100 Message-Id: <20210205140653.578210069@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210205140652.348864025@linuxfoundation.org> References: <20210205140652.348864025@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Bing Guo [ Upstream commit 4716a7c50c5c66d6ddc42401e1e0ba13b492e105 ] Why: Function decide_dp_link_settings() loops infinitely when required bandwidth can't be supported. How: Check the required bandwidth against verified_link_cap before trying to find a link setting for it. Tested-by: Daniel Wheeler Signed-off-by: Bing Guo Reviewed-by: Jun Lei Acked-by: Anson Jacob Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c index 959eb075d11ed..c18f39271b034 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c @@ -1914,6 +1914,9 @@ static bool decide_dp_link_settings(struct dc_link *link, struct dc_link_setting initial_link_setting; uint32_t link_bw; + if (req_bw > dc_link_bandwidth_kbps(link, &link->verified_link_cap)) + return false; + /* search for the minimum link setting that: * 1. is supported according to the link training result * 2. could support the b/w requested by the timing -- 2.27.0