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 AFFF1C6FD1D for ; Wed, 15 Mar 2023 09:09:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232030AbjCOJJW (ORCPT ); Wed, 15 Mar 2023 05:09:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52754 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230393AbjCOJIt (ORCPT ); Wed, 15 Mar 2023 05:08:49 -0400 Received: from mail-wr1-x42c.google.com (mail-wr1-x42c.google.com [IPv6:2a00:1450:4864:20::42c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DD21024BD9 for ; Wed, 15 Mar 2023 02:08:24 -0700 (PDT) Received: by mail-wr1-x42c.google.com with SMTP id h17so2582271wrt.8 for ; Wed, 15 Mar 2023 02:08:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1678871303; h=content-transfer-encoding:in-reply-to:organization:content-language :references:cc:to:subject:reply-to:from:user-agent:mime-version:date :message-id:from:to:cc:subject:date:message-id:reply-to; bh=qSsckNSpK1c9n86p4aO+c/oJA0ycZxu7SJjrPE+HAQ8=; b=tmD+UjAkWr8b4XsqB22P78X5JUKvi1YiIAUkHzNKUDz9uIw8cl5dkhRRf1Q52iPRl+ NpRzWkRVDz73h1W9Tsp4mwAXY0QStTNh1x0ueCYwTV010cngmmPZAhH37/5hJvYPIaO2 yQ+7azjTlIF122DsaMci1HP0fY/hRzsiGfOju0Pn7gb1iRZjiOuCbjpYr3a/bRICH7+3 rTkUFw73fmcrrsrueLMJLucDVk999FHjjZly8TbRJSlDd75zYikzavlRLGTzimDcdYQw VzfBiKbsQKFmkKVCkuSUVjlQHYkytLrcp5COcTm6Bgq/PBH9GcMFdtAFg5+zZpSe5I9j A8aQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1678871303; h=content-transfer-encoding:in-reply-to:organization:content-language :references:cc:to:subject:reply-to:from:user-agent:mime-version:date :message-id:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=qSsckNSpK1c9n86p4aO+c/oJA0ycZxu7SJjrPE+HAQ8=; b=V2w9wD+dpwHH8VoU05wr7RCS3b6415gm7GUeoWVpHzwNr4EMR8gy9BecFvtZmJfb9T ze6ff4xAbBi3nfxLqDr8Oyo5xF0VtsMLrFoUdyHR3F5q8F6OdN+8aTRGkccEKIZi3Fos odbfa5Aj8ukRkZgrBbZgWq3eOL5D98X5M0BraJKEB7ghdpETZJuLwXZPH663XBH0siZT /6Zf0HEcNsShCbnmv9SqJYNGEZp0OTJq7ilXc0aHaPcSI94mj/acuy1frtMy5yNCQQfm AsMPGPmVoqrArvFO391D2KuANPqmg0AqPbVQzlR91239rxWxOoqdUt8hhih/HbURane2 JfCA== X-Gm-Message-State: AO0yUKUBQEAUeM88jA70B2756ICcpRccRv66lP4pnJvPLdVOfAdAfFKb gSHYO946/9IeM7/rCtIDxfarYA== X-Google-Smtp-Source: AK7set/VD7eCD1LIq0xwBIFKZji2Qq6fk458HtzGpOXLjPiHI+9hyptBnXREbMtiE96CAt3f1xsd8A== X-Received: by 2002:a5d:4985:0:b0:2cf:f140:52e3 with SMTP id r5-20020a5d4985000000b002cff14052e3mr1263706wrq.9.1678871303389; Wed, 15 Mar 2023 02:08:23 -0700 (PDT) Received: from ?IPV6:2a01:e0a:982:cbb0:5d2d:8427:397b:8fe7? ([2a01:e0a:982:cbb0:5d2d:8427:397b:8fe7]) by smtp.gmail.com with ESMTPSA id b11-20020a5d550b000000b002bfd524255esm4121784wrv.43.2023.03.15.02.08.22 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 15 Mar 2023 02:08:22 -0700 (PDT) Message-ID: Date: Wed, 15 Mar 2023 10:08:21 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.8.0 From: neil.armstrong@linaro.org Reply-To: neil.armstrong@linaro.org Subject: Re: [PATCH] drm/bridge: adv7511: fix race condition bug in adv7511_remove due to unfinished work To: Zheng Wang , dri-devel@lists.freedesktop.org Cc: andrzej.hajda@intel.com, jonas@kwiboo.se, airlied@gmail.com, daniel@ffwll.ch, linux-kernel@vger.kernel.org, hackerzheng666@gmail.com, 1395428693sheep@gmail.com, alex000young@gmail.com References: <20230308173433.2788833-1-zyytlz.wz@163.com> Content-Language: en-US Organization: Linaro Developer Services In-Reply-To: <20230308173433.2788833-1-zyytlz.wz@163.com> 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 Hi, On 08/03/2023 18:34, Zheng Wang wrote: > In adv7511_probe, adv7511->hpd_work is bound with adv7511_hpd_work. > If we call adv7511_remove with a unfinished work. There may be a > race condition where bridge->hpd_mutex was destroyed by > drm_bridge_remove and used in adv7511_hpd_work in drm_bridge_hpd_notify. > > Fix it by canceling the work before cleanup in adv7511_remove. > Can you add the relevant Fixes tag ? Thanks, Neil > Signed-off-by: Zheng Wang > --- > drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c > index ddceafa7b637..9bf72dd6c1d3 100644 > --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c > +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c > @@ -1349,6 +1349,7 @@ static void adv7511_remove(struct i2c_client *i2c) > { > struct adv7511 *adv7511 = i2c_get_clientdata(i2c); > > + cancel_work_sync(&adv7511->hpd_work); > adv7511_uninit_regulators(adv7511); > > drm_bridge_remove(&adv7511->bridge);