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 788EAC77B7C for ; Wed, 10 May 2023 02:17:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230199AbjEJCR5 (ORCPT ); Tue, 9 May 2023 22:17:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40408 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229595AbjEJCR4 (ORCPT ); Tue, 9 May 2023 22:17:56 -0400 Received: from mail-pl1-x634.google.com (mail-pl1-x634.google.com [IPv6:2607:f8b0:4864:20::634]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5F205BF for ; Tue, 9 May 2023 19:17:55 -0700 (PDT) Received: by mail-pl1-x634.google.com with SMTP id d9443c01a7336-1ab0595fc69so10979985ad.0 for ; Tue, 09 May 2023 19:17:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20221208.gappssmtp.com; s=20221208; t=1683685075; x=1686277075; h=content-transfer-encoding:in-reply-to:from:references:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=wMJx/u/pBYVd7Zt4eeqFR3I/fhY0U5ZXB++bJG0vXno=; b=SZEUJlGBuDB3sRwE0D/8GD4meNu7D2ZykHyEdRQA1nG96faLOaQgdSi1FM2VUR0ol5 YPn5q3KPXEgKzUTYl273YA6Q1D/unrkk6BLetzJwChr9/rmC30chg7a+zcGj7Lry5fKR MYGt+7K9yLWgCeqqhDTRIG7MBhVtRHY3NdA0dWRvK23W4vsoADNG6KcoLDp/vaW0cW/t zFYd5hSRNZqG666tV13mzwZlMiK0f0lAAn8UgkwN26oN+mKNXsHpcrAm2rMnK460oA4i R66nv95do3v/+lvUQu2FZu3WcxBTdyE42eNvTy/uue2e6pO18KhV1WY2IlreC+Agj89d NnjQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683685075; x=1686277075; h=content-transfer-encoding:in-reply-to:from:references: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=wMJx/u/pBYVd7Zt4eeqFR3I/fhY0U5ZXB++bJG0vXno=; b=CZ1T27kVhG0OUQJ/u4kZkllEq3e0XH8/2G2bGEjoDScmKoVFQvfZrOeP0+4weZcLdd DSp4HZZUHojOMegwl7otSKAy1MG5ozTtrbOdpvwHHS/xhAHMQaLudqd//0enFUzv4L79 9DRkFPvF0eIkuYkRa3YqXuNXRQbzDQKB+7dYEpVvkPA+ERT9FCJtoJQZFt57KG09USzv 393nonAheRBz7u+4YYrEw1aI5V9LNfeSq4RoeT+pexyCyTJKQCj5HYnYQyc/DSyRTwHH 91/WA650zXseKpjuYbr67w3RJKbZEQhpVMSaBUkZdN0drPkK7+jQXfrAAbayVWDhvShR LG2g== X-Gm-Message-State: AC+VfDzs5+cwl6QPm8lyYvoN/asZk5OJQsCIVweSbS5T41WPmFvgFTWN 0gx7T2mTU1mD1/+IVk+AUV3lqg== X-Google-Smtp-Source: ACHHUZ63SBLSE29exYA5LPsG2pRkV8oXtGxZr/XXJIPvu7KlYtPUBOSp7qEDUVJiCI/bIb/nd/mjUg== X-Received: by 2002:a17:902:cec7:b0:1ac:6153:50b3 with SMTP id d7-20020a170902cec700b001ac615350b3mr15056493plg.5.1683685074847; Tue, 09 May 2023 19:17:54 -0700 (PDT) Received: from [192.168.1.136] ([198.8.77.157]) by smtp.gmail.com with ESMTPSA id bb5-20020a170902bc8500b001ab05aaae2fsm2361211plb.107.2023.05.09.19.17.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 09 May 2023 19:17:54 -0700 (PDT) Message-ID: <1155743b-2073-b778-1ec5-906300e0570a@kernel.dk> Date: Tue, 9 May 2023 20:17:53 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:102.0) Gecko/20100101 Thunderbird/102.10.0 Subject: Re: [bug report] BUG: kernel NULL pointer dereference, address: 0000000000000048 Content-Language: en-US To: Yu Kuai , Guangwu Zhang , linux-block@vger.kernel.org, io-uring@vger.kernel.org, Jeff Moyer , Ming Lei , "yukuai (C)" References: <007af59f-4f4c-f779-a1b6-aaa81ff640b3@huaweicloud.com> From: Jens Axboe In-Reply-To: <007af59f-4f4c-f779-a1b6-aaa81ff640b3@huaweicloud.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 5/9/23 8:00?PM, Yu Kuai wrote: > Hi, > > ? 2023/05/10 9:49, Yu Kuai ??: >> Hi, >> >> ? 2023/05/10 9:29, Yu Kuai ??: >>> Hi, >>> >>> ? 2023/05/10 8:49, Guangwu Zhang ??: >>>> Hi, >>>> >>>> We found this kernel NULL pointer issue with latest >>>> linux-block/for-next, please check it. >>>> >>>> Kernel repo: https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git >>>> >>>> >>>> [ 112.483804] BUG: kernel NULL pointer dereference, address: 0000000000000048 >> >> Base on this offset, 0x48 match bio->bi_blkg, so I guess this is because >> bio is NULL, so the problem is that passthrough request insert into >> elevator. >> > Sorry that attached patch has some problem, please try this one. Let's please fix this in bfq, this isn't a core issue and it's not a good idea to work around it there. -- Jens Axboe