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 963D6C77B6C for ; Fri, 7 Apr 2023 19:45:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229575AbjDGTpy (ORCPT ); Fri, 7 Apr 2023 15:45:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41132 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229523AbjDGTpw (ORCPT ); Fri, 7 Apr 2023 15:45:52 -0400 Received: from mail-pl1-f177.google.com (mail-pl1-f177.google.com [209.85.214.177]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 875079028; Fri, 7 Apr 2023 12:45:50 -0700 (PDT) Received: by mail-pl1-f177.google.com with SMTP id d9443c01a7336-1a51d304648so498825ad.3; Fri, 07 Apr 2023 12:45:50 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1680896750; x=1683488750; h=content-transfer-encoding:in-reply-to:content-language:references :cc:to:subject:from:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=CWghzBfKuQahtLumYRFLf1CL+ff9yd1SjNGPejMxZk8=; b=rkYhPdfx26R6YooQeIUmRf+PnwngkGGje8A2PlgFRnFYtlT8QHJ9SW0bgiaj1wcsCw fRCxCkKkJ1WbmfyibzsUX4DpcrWHwT4SIUlkEfVtOZYTCRbtG9RmIkelN2C+rCHSG5zd qMUhjClmIWzSAslaS8qBR3k8mEw8/m2uX4i6+kLX0z2nWQ7VH3v3l2YEhh5YOJNtY5Cy mUasTz1GLrOvLl83lUpIEZQG7jfuW0KNvKK/i8zDBWqSY9q3J9OlgFaI87tR+7Tc3D4W C0rA/kGZWxEv/pJCZEIvO+hkjQsPGwJqUMV1LkBtS4bpBNmClIfrT6M16N75hv5wvIJM vpOA== X-Gm-Message-State: AAQBX9eD9B6IBKsv/sws+/VM2+xsgtO8hUiLAqwiHNyHVcDhgGrVi41+ 7rPGx3mAZvo1KDFaDKglSL0YjOEvXoQ= X-Google-Smtp-Source: AKy350Zvf+ZYs9X20b1qMpn53sbWEJeeG8LMZ6lU+gEvqgWHqGO3zOmD3Xp5o3DiTs1Lha5jhvsRAg== X-Received: by 2002:aa7:8bd1:0:b0:62a:9d6f:98dc with SMTP id s17-20020aa78bd1000000b0062a9d6f98dcmr3444446pfd.11.1680896749761; Fri, 07 Apr 2023 12:45:49 -0700 (PDT) Received: from ?IPV6:2620:15c:211:201:f2c:4ac2:6000:5900? ([2620:15c:211:201:f2c:4ac2:6000:5900]) by smtp.gmail.com with ESMTPSA id f27-20020a631f1b000000b0051322ab5ccdsm3001289pgf.28.2023.04.07.12.45.48 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 07 Apr 2023 12:45:49 -0700 (PDT) Message-ID: <63cf4e4f-764b-8634-b29f-30d45bed1ca5@acm.org> Date: Fri, 7 Apr 2023 12:45:47 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.7.1 From: Bart Van Assche Subject: Re: [PATCH v2 0/3] blk-cgroup: some cleanup To: Jens Axboe , Chengming Zhou , tj@kernel.org Cc: paolo.valente@linaro.org, josef@toxicpanda.com, linux-block@vger.kernel.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org References: <20230406145050.49914-1-zhouchengming@bytedance.com> <1416b648-188f-873a-08b3-c8e8494ab1a7@kernel.dk> Content-Language: en-US In-Reply-To: <1416b648-188f-873a-08b3-c8e8494ab1a7@kernel.dk> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/7/23 11:44, Jens Axboe wrote: > On 4/7/23 12:41 PM, Bart Van Assche wrote: >> On 4/6/23 07:50, Chengming Zhou wrote: >>> These are some cleanup patches of blk-cgroup. Thanks for review. >> >> With these patches applied, my kernel test VM crashes during boot. The following crash disappears if I revert these patches: >> >> BUG: KASAN: null-ptr-deref in bio_associate_blkg_from_css+0x83/0x240 > > Would be useful in the report to know where that is, as it doesn't include > the code output. Hi Jens, This is what gdb tells me about the crash address: $ gdb vmlinux (gdb) list *(bio_associate_blkg_from_css+0x83) 0xffffffff81856923 is in bio_associate_blkg_from_css (./include/linux/blkdev.h:865). 860 int iocb_bio_iopoll(struct kiocb *kiocb, struct io_comp_batch *iob, 861 unsigned int flags); 862 863 static inline struct request_queue *bdev_get_queue(struct block_device *bdev) 864 { 865 return bdev->bd_queue; /* this is never NULL */ 866 } 867 868 /* Helper to convert BLK_ZONE_ZONE_XXX to its string format XXX */ 869 const char *blk_zone_cond_str(enum blk_zone_cond zone_cond); Thanks, Bart.