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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7CFB9C54EBD for ; Sun, 8 Jan 2023 21:56:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236098AbjAHV4O (ORCPT ); Sun, 8 Jan 2023 16:56:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48374 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231926AbjAHV4L (ORCPT ); Sun, 8 Jan 2023 16:56:11 -0500 Received: from mail-lf1-x132.google.com (mail-lf1-x132.google.com [IPv6:2a00:1450:4864:20::132]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 169927664 for ; Sun, 8 Jan 2023 13:56:10 -0800 (PST) Received: by mail-lf1-x132.google.com with SMTP id v25so10216006lfe.12 for ; Sun, 08 Jan 2023 13:56:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=6e8O8V82C5N5Vb0KJCfa+OtRNISoBAeakdYZbJjo70I=; b=raLWVm7qNmusfNaKZbuYvMr1H/R2jjVHDWBRtsuze6qnSAFV2T75dP0NSoc0b6/5Ad RfL+3pA28APIv55CCUkBN5AGuddLKduXNZ7kmbO0e9WQYgxbtEcsjHrv2QmG8wEtJ/GT MwCsH7tUzrPPSQ6mfqxOaEkKy2+6pGKbL/CR3tYOvEoM/xZ6JgEpn7X/L3dSS8UV9y+N zIh9hwxCorIIP9WXULKAkpj9uuZF0+0bWY+kDfHvEfROOgo+Z0uC3Nl/ytWUP0YGeaw9 lkn4KykT94f5I/xRRFrJBW5qKoyNiDmXDYTxv6d1uCRmA6/tokgPPToci5a4WisrlunN +mww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=6e8O8V82C5N5Vb0KJCfa+OtRNISoBAeakdYZbJjo70I=; b=nqWSTte3L6Pimo1hwqdH62cT1c85xs1k6XXn3SCiWWZOPJgXgc4LTuF1Ax42IkNrb9 vOwiZb8R+kKeC08kbpGuDnvSRAd3ali4N7xPetxibdJHZW5r1yZ/V4IT3e7MO0H9yVhj sOwDZ4xRlMQydkXYLrgyFYd8paFt2X4MlFM1pEuTe/boG/FiOBrxL3bpN9OtcDF+2rKo SkRCXRkBq6vFBqWJY1lOnWta/28D9ckTyj8YS6qxDH90WuDeregXpNZ2KywULHY9e8bM 0UNKJ4bNWmvIErOvRuEev4ScvLA5VT9YDTscauNoF+QSREmnf4530mGPiFV1Oox8Q+Si +UwQ== X-Gm-Message-State: AFqh2kq51ZQZHbWL+u7tLGbXzJrq8qkofxxfFpXXpZGI3tIWJfo5z+Jh kp4/TgHzuZspplQSe6dwG4flMA== X-Google-Smtp-Source: AMrXdXvKo2BtT7e7Uk53Mqd4oozSlCHiPGbx4Ag+iv04st1VBFMwsT1AQnDkXGlmcDc76falNTAJ7w== X-Received: by 2002:ac2:482d:0:b0:4ba:555f:4799 with SMTP id 13-20020ac2482d000000b004ba555f4799mr11450200lft.16.1673214968460; Sun, 08 Jan 2023 13:56:08 -0800 (PST) Received: from ?IPV6:2001:14ba:a085:4d00::8a5? (dzccz6yyyyyyyyyyybcwt-3.rev.dnainternet.fi. [2001:14ba:a085:4d00::8a5]) by smtp.gmail.com with ESMTPSA id c19-20020a056512075300b004b15bc0ff63sm1239096lfs.277.2023.01.08.13.56.07 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 08 Jan 2023 13:56:08 -0800 (PST) Message-ID: Date: Sun, 8 Jan 2023 23:56:07 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.6.0 Subject: Re: [PATCH] drm/msm/dpu: Add check for cstate Content-Language: en-GB To: Jiasheng Jiang , robdclark@gmail.com, quic_abhinavk@quicinc.com, sean@poorly.run, airlied@gmail.com, daniel@ffwll.ch, quic_jesszhan@quicinc.com, ville.syrjala@linux.intel.com, yang.lee@linux.alibaba.com Cc: linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, linux-kernel@vger.kernel.org References: <20221206080517.43786-1-jiasheng@iscas.ac.cn> From: Dmitry Baryshkov In-Reply-To: <20221206080517.43786-1-jiasheng@iscas.ac.cn> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/12/2022 10:05, Jiasheng Jiang wrote: > As kzalloc may fail and return NULL pointer, > it should be better to check cstate > in order to avoid the NULL pointer dereference > in __drm_atomic_helper_crtc_reset. > > Fixes: 1cff7440a86e ("drm/msm: Convert to using __drm_atomic_helper_crtc_reset() for reset.") > Signed-off-by: Jiasheng Jiang > --- > drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c > index 13ce321283ff..22c2787b7b38 100644 > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c > @@ -968,7 +968,10 @@ static void dpu_crtc_reset(struct drm_crtc *crtc) > if (crtc->state) > dpu_crtc_destroy_state(crtc, crtc->state); > > - __drm_atomic_helper_crtc_reset(crtc, &cstate->base); > + if (cstate) > + __drm_atomic_helper_crtc_reset(crtc, &cstate->base); > + else > + __drm_atomic_helper_crtc_reset(crtc, NULL); NAK. The proper fix is to add the if() but to skip the else clause. We should not reset the crtc's state if memory allocation failed. > } > > /** -- With best wishes Dmitry