From patchwork Fri Feb 18 10:03:46 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= X-Patchwork-Id: 12751214 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 06B73C433EF for ; Fri, 18 Feb 2022 10:04:39 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 96AAA10EB87; Fri, 18 Feb 2022 10:04:36 +0000 (UTC) Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6836A10EB87; Fri, 18 Feb 2022 10:04:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1645178675; x=1676714675; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=ip7yh9TtqNGqyNAUmnumyaTaXv9TKkgX3VCmbjFMhFc=; b=GV1lrokZGa3Yvuxx60iyg+ldMrCkBlIlToYtnMTYqQ6pxqNMp4i8VTW5 1trpWr14dFv3ojNCmcHoj7vobv2YO+2Mi0PbXN9Nc2QMS0wi8379bePuw B2ebdoYQwuuB7yd+f4s4HLFHkDh4ZogF7lL4SgoRN2lg86S0t3w/4hDuK EMskQgye+1Iq6T61UJKAhgAj6Z5AIbaYvYbM+UgqA0ZpuRKQ/OLq5GZHq TaC+KaQNDggtmjIF/DO8rE35QBH+PMvT41sWoofMJbuYQBsZvi1uPHjNR /MARanwwjp3I12xCmA7oRZ6/qlgzEAKh/HsXtVFwu7RtSPkkLUOA3CAxX Q==; X-IronPort-AV: E=McAfee;i="6200,9189,10261"; a="337541322" X-IronPort-AV: E=Sophos;i="5.88,378,1635231600"; d="scan'208";a="337541322" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Feb 2022 02:04:34 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,378,1635231600"; d="scan'208";a="503950870" Received: from stinkpipe.fi.intel.com (HELO stinkbox) ([10.237.72.151]) by orsmga002.jf.intel.com with SMTP; 18 Feb 2022 02:04:31 -0800 Received: by stinkbox (sSMTP sendmail emulation); Fri, 18 Feb 2022 12:04:31 +0200 From: Ville Syrjala To: dri-devel@lists.freedesktop.org Subject: [PATCH 05/22] drm/radeon: Use drm_mode_copy() Date: Fri, 18 Feb 2022 12:03:46 +0200 Message-Id: <20220218100403.7028-6-ville.syrjala@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220218100403.7028-1-ville.syrjala@linux.intel.com> References: <20220218100403.7028-1-ville.syrjala@linux.intel.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alex Deucher , intel-gfx@lists.freedesktop.org, amd-gfx@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Ville Syrjälä struct drm_display_mode embeds a list head, so overwriting the full struct with another one will corrupt the list (if the destination mode is on a list). Use drm_mode_copy() instead which explicitly preserves the list head of the destination mode. Even if we know the destination mode is not on any list using drm_mode_copy() seems decent as it sets a good example. Bad examples of not using it might eventually get copied into code where preserving the list head actually matters. Obviously one case not covered here is when the mode itself is embedded in a larger structure and the whole structure is copied. But if we are careful when copying into modes embedded in structures I think we can be a little more reassured that bogus list heads haven't been propagated in. @is_mode_copy@ @@ drm_mode_copy(...) { ... } @depends on !is_mode_copy@ struct drm_display_mode *mode; expression E, S; @@ ( - *mode = E + drm_mode_copy(mode, &E) | - memcpy(mode, E, S) + drm_mode_copy(mode, E) ) @depends on !is_mode_copy@ struct drm_display_mode mode; expression E; @@ ( - mode = E + drm_mode_copy(&mode, &E) | - memcpy(&mode, E, S) + drm_mode_copy(&mode, E) ) @@ struct drm_display_mode *mode; @@ - &*mode + mode Cc: Alex Deucher Cc: amd-gfx@lists.freedesktop.org Signed-off-by: Ville Syrjälä --- drivers/gpu/drm/radeon/radeon_connectors.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c index a7925a8290b2..0cb1345c6ba4 100644 --- a/drivers/gpu/drm/radeon/radeon_connectors.c +++ b/drivers/gpu/drm/radeon/radeon_connectors.c @@ -777,7 +777,7 @@ static void radeon_fixup_lvds_native_mode(struct drm_encoder *encoder, if (mode->type & DRM_MODE_TYPE_PREFERRED) { if (mode->hdisplay != native_mode->hdisplay || mode->vdisplay != native_mode->vdisplay) - memcpy(native_mode, mode, sizeof(*mode)); + drm_mode_copy(native_mode, mode); } } @@ -786,7 +786,7 @@ static void radeon_fixup_lvds_native_mode(struct drm_encoder *encoder, list_for_each_entry_safe(mode, t, &connector->probed_modes, head) { if (mode->hdisplay == native_mode->hdisplay && mode->vdisplay == native_mode->vdisplay) { - *native_mode = *mode; + drm_mode_copy(native_mode, mode); drm_mode_set_crtcinfo(native_mode, CRTC_INTERLACE_HALVE_V); DRM_DEBUG_KMS("Determined LVDS native mode details from EDID\n"); break;