From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-m83227.xmail.ntesmail.com (mail-m83227.xmail.ntesmail.com [156.224.83.227]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 27470220F36; Tue, 29 Jul 2025 03:22:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=156.224.83.227 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753759379; cv=none; b=up+RH8crifrKVSgs6YPejxVROKVRyqa0RNAype4/SjScqv5v6qbbuii5JsnCs5NvfrnWfNAF6SAZ4TVMikTLmzeNkbAL0W0vRu97zJkhKza14jWpv/XpoSBTEfWcgHmzxfZc8uIRmGrnotDnRCkY9wQqMpDapVbjxGv8F5aeme4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753759379; c=relaxed/simple; bh=SnM1UAE7l7E3vA4a9C/h0NwsuzBKmJHC2GnuVYscJPk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=XJoVdPVnAvlgwfBHp9k1KVIOD5L3U2KE+5tdC95a4uYGMQ4biddXEZA1lkzjRytY1diloKy2KLhYijJucrz85FCPI7hKRZp9YoorQnRNUOWOqUZN0uNjdR0xfA6GNpkjPmJ6vmwQDnDp0ojGkMBqlcI1WBNI1oH//Yr3pfjQXyY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rock-chips.com; spf=pass smtp.mailfrom=rock-chips.com; dkim=pass (1024-bit key) header.d=rock-chips.com header.i=@rock-chips.com header.b=LiMF/V4r; arc=none smtp.client-ip=156.224.83.227 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rock-chips.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rock-chips.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=rock-chips.com header.i=@rock-chips.com header.b="LiMF/V4r" Received: from [172.16.12.26] (unknown [58.22.7.114]) by smtp.qiye.163.com (Hmail) with ESMTP id 1d8de167e; Tue, 29 Jul 2025 11:22:50 +0800 (GMT+08:00) Message-ID: <63226b37-1dec-4998-b2b6-e969ca786f37@rock-chips.com> Date: Tue, 29 Jul 2025 11:22:49 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 03/14] drm/rockchip: analogix_dp: Apply drmm_encoder_init() instead of drm_simple_encoder_init() To: Dmitry Baryshkov Cc: andrzej.hajda@intel.com, neil.armstrong@linaro.org, rfoss@kernel.org, Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, airlied@gmail.com, simona@ffwll.ch, jingoohan1@gmail.com, inki.dae@samsung.com, sw0312.kim@samsung.com, kyungmin.park@samsung.com, krzk@kernel.org, alim.akhtar@samsung.com, hjc@rock-chips.com, heiko@sntech.de, andy.yan@rock-chips.com, l.stach@pengutronix.de, dianders@chromium.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-rockchip@lists.infradead.org References: <20250724080304.3572457-1-damon.ding@rock-chips.com> <20250724080304.3572457-4-damon.ding@rock-chips.com> <6psjcrhbnk7czdrdtxh65kr6qvygkwogvert75dg2svbm2cqd3@uhffyfdxqpec> Content-Language: en-US From: Damon Ding In-Reply-To: <6psjcrhbnk7czdrdtxh65kr6qvygkwogvert75dg2svbm2cqd3@uhffyfdxqpec> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-HM-Tid: 0a9854344c1803a3kunmbc6d5ef53b5bbd X-HM-MType: 1 X-HM-Spam-Status: e1kfGhgUHx5ZQUpXWQgPGg8OCBgUHx5ZQUlOS1dZFg8aDwILHllBWSg2Ly tZV1koWUFDSUNOT01LS0k3V1ktWUFJV1kPCRoVCBIfWUFZGklKGlZIHx1LHkkeSx9DH09WFRQJFh oXVRMBExYaEhckFA4PWVdZGBILWUFZTkNVSUlVTFVKSk9ZV1kWGg8SFR0UWUFZT0tIVUpLSU9PT0 hVSktLVUpCS0tZBg++ DKIM-Signature: a=rsa-sha256; b=LiMF/V4rH3QqRzk0VLBeqKLCLbx/NP1Emxe528xmhWl9Zye0NFzYX4UPlWJWn/fBxk/znUKcFCVyqFWK/urEAE3LRP6IEmQNllUopbTDUvA9KZ7BnHHZB1R5zzAf8eLa+eIeuBYiAe2DouhqA3FKqaEfD9JHKsZvXXMvHM6RQTY=; c=relaxed/relaxed; s=default; d=rock-chips.com; v=1; bh=n/oZwA3AlTNfmx4P7C3GWExCuKTHEtbzFqxGSx8S9/k=; h=date:mime-version:subject:message-id:from; Hi Dmitry, On 2025/7/26 8:12, Dmitry Baryshkov wrote: > On Thu, Jul 24, 2025 at 04:02:53PM +0800, Damon Ding wrote: >> Compared with drm_simple_encoder_init(), drmm_encoder_init() can handle >> the cleanup automatically through registering drm_encoder_cleanup() with >> drmm_add_action(). >> >> Signed-off-by: Damon Ding >> --- >> drivers/gpu/drm/rockchip/analogix_dp-rockchip.c | 4 +--- >> 1 file changed, 1 insertion(+), 3 deletions(-) >> >> diff --git a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c >> index d30f0983a53a..4ed6bf9e5377 100644 >> --- a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c >> +++ b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c >> @@ -29,7 +29,6 @@ >> #include >> #include >> #include >> -#include >> >> #include "rockchip_drm_drv.h" >> >> @@ -377,8 +376,7 @@ static int rockchip_dp_drm_create_encoder(struct rockchip_dp_device *dp) >> dev->of_node); >> DRM_DEBUG_KMS("possible_crtcs = 0x%x\n", encoder->possible_crtcs); >> >> - ret = drm_simple_encoder_init(drm_dev, encoder, >> - DRM_MODE_ENCODER_TMDS); >> + ret = drmm_encoder_init(drm_dev, encoder, NULL, DRM_MODE_ENCODER_TMDS, NULL); > > It's not possible to use drmm_encoder_init() here. Per the documentation > the encoder data structure should be allocated by drmm_kzalloc(). > However this drm_encoder is a part of struct rockchip_dp_device. It's > allocated by rockchip_dp_probe() via devm_kzalloc(). This means that it > can potentially be freed before the drm device is completely released, > creating a use-after-free error. > >> if (ret) { >> DRM_ERROR("failed to initialize encoder with drm\n"); >> return ret; >> -- >> 2.34.1 >> > Got it. This patch will be dropped in the next version. Best regards, Damon