From nobody Wed Dec 17 02:32:15 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6981BC4167B for ; Thu, 30 Nov 2023 14:17:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345954AbjK3ORP (ORCPT ); Thu, 30 Nov 2023 09:17:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345930AbjK3ORL (ORCPT ); Thu, 30 Nov 2023 09:17:11 -0500 Received: from mail-ed1-x52e.google.com (mail-ed1-x52e.google.com [IPv6:2a00:1450:4864:20::52e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D404F85 for ; Thu, 30 Nov 2023 06:17:17 -0800 (PST) Received: by mail-ed1-x52e.google.com with SMTP id 4fb4d7f45d1cf-54bfa9b3ffaso1116953a12.1 for ; Thu, 30 Nov 2023 06:17:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amarulasolutions.com; s=google; t=1701353836; x=1701958636; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=fu0Px4Tbxip0tKoFWKIyTvbcuMI1IJ2fyAiFtPcJOWc=; b=WKUeHvW1UfvIzoIM+Zt/rulv0IcAV84RRBZR2M9w+hEa2zTAkcpXUF6qRBGaJvF8qT jkzCuRSgpiSm2+wL/YmT8OIWDtisvmGogX4AD/OfzWui44McQKJPsHe6tmZhjY8Cnqtw duO86GnfrgKNjbaa5s1bosIXPWorU6xArM/NI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701353836; x=1701958636; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=fu0Px4Tbxip0tKoFWKIyTvbcuMI1IJ2fyAiFtPcJOWc=; b=GfBhR+ynLp5qogncFz59Akjw6wlGCncI88sOTYJCdcoN5JrSMEgUyPPkrS+1+QR7a0 PjuZLFayc3MAibq2sBsV1Db5exGI1RP0arGXRaqw6uXUaDr/kAhM6o1aTWT73vPG7ail uOR/jqZ8VXWmMlkYfiUik+UyPPxr6rAYIAgJc0J8lDD2TW4VkZ9M2wVxsIWSPR+wKaBA OZlYD8Qnrq4ISREQShwOPVPO7U4xdsKx+NUHJ95g0FOG4PzFPTzAeLD5RXcacikPElJ5 +piPAm4QDdwWd6cazYggMkghrbrvnl+aQQ6od/aa7k9Q2tH2/5Udrz98h9gRb7eM61VO 3Ybg== X-Gm-Message-State: AOJu0Ywss+lz0IRuKEQbr8MRmu36gPB7BiR7j6RHSDtsxT6fCUVnpbsX EAqvpjMcoKLMtrstPtiT00Qp9JYqrl76zAVGR2/QCA== X-Google-Smtp-Source: AGHT+IGPJFSHiwsvUjkjxeqqI3O330KX4fQMrY818rLAIKFMtGBlIdjSgFv6U+hzidftmcj4vVW8XQ== X-Received: by 2002:a17:907:1051:b0:a18:bb79:9a0 with SMTP id oy17-20020a170907105100b00a18bb7909a0mr1186409ejb.58.1701353835975; Thu, 30 Nov 2023 06:17:15 -0800 (PST) Received: from localhost.localdomain ([2001:b07:6474:ebbf:d1eb:b106:516d:db0a]) by smtp.gmail.com with ESMTPSA id my18-20020a1709065a5200b009f28db2b702sm716064ejc.209.2023.11.30.06.17.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 30 Nov 2023 06:17:15 -0800 (PST) From: Dario Binacchi To: linux-kernel@vger.kernel.org Cc: Amarula patchwork , michael@amarulasolutions.com, Dario Binacchi , Andrzej Hajda , Daniel Vetter , Dave Stevenson , David Airlie , Frieder Schrempf , Jernej Skrabec , Jonas Karlman , Laurent Pinchart , Maarten Lankhorst , Maxime Ripard , Neil Armstrong , Robert Foss , Thomas Zimmermann , dri-devel@lists.freedesktop.org Subject: [PATCH v3 02/10] drm/bridge: Fix a use case in the bridge disable logic Date: Thu, 30 Nov 2023 15:16:19 +0100 Message-ID: <20231130141705.1796672-3-dario.binacchi@amarulasolutions.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231130141705.1796672-1-dario.binacchi@amarulasolutions.com> References: <20231130141705.1796672-1-dario.binacchi@amarulasolutions.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The patch fixes the code for finding the next bridge with the "pre_enable_prev_first" flag set to false. In case this condition is not verified, i. e. there is no subsequent bridge with the flag set to false, the whole bridge list is traversed, invalidating the "next" variable. The use of a new iteration variable (i. e. "iter") ensures that the value of the "next" variable is not invalidated. Fixes: 4fb912e5e190 ("drm/bridge: Introduce pre_enable_prev_first to alter = bridge init order") Co-developed-by: Michael Trimarchi Signed-off-by: Michael Trimarchi Signed-off-by: Dario Binacchi --- (no changes since v1) drivers/gpu/drm/drm_bridge.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index f66bf4925dd8..2e5781bf192e 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -662,7 +662,7 @@ void drm_atomic_bridge_chain_post_disable(struct drm_br= idge *bridge, struct drm_atomic_state *old_state) { struct drm_encoder *encoder; - struct drm_bridge *next, *limit; + struct drm_bridge *iter, *next, *limit; =20 if (!bridge) return; @@ -680,14 +680,15 @@ void drm_atomic_bridge_chain_post_disable(struct drm_= bridge *bridge, * was enabled first, so disabled last */ limit =3D next; + iter =3D next; =20 /* Find the next bridge that has NOT requested * prev to be enabled first / disabled last */ - list_for_each_entry_from(next, &encoder->bridge_chain, + list_for_each_entry_from(iter, &encoder->bridge_chain, chain_node) { - if (!next->pre_enable_prev_first) { - next =3D list_prev_entry(next, chain_node); + if (!iter->pre_enable_prev_first) { + next =3D list_prev_entry(iter, chain_node); limit =3D next; break; } --=20 2.43.0