From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on gnuweeb.org X-Spam-Level: X-Spam-Status: No, score=-1.8 required=5.0 tests=ALL_TRUSTED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,NICE_REPLY_A,NO_DNS_FOR_FROM, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 Received: from [192.168.88.87] (unknown [180.242.99.67]) by gnuweeb.org (Postfix) with ESMTPSA id 85C6C7E3F3; Thu, 19 May 2022 17:41:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gnuweeb.org; s=default; t=1652982108; bh=VhmYVAfFGBmzr0XyrvcJgpmcwcLIM0l8TtrBD+fhp4Q=; h=Date:To:Cc:References:From:Subject:In-Reply-To:From; b=O8IeVTylByXxEbuUc76ARTVIopsN57qQw0VgoJrK1d0fnMqF6CP0YCJLYQFc7v7XJ zdVCfSnc12ekdgZC7OBhBJ21//PYeVSLyz7LZQ4DNHOAidjMYDehDpeM3+SsMIuKwO RdEK1ZacSra9wGsDNMkmqDzka0UROumKEABH2suMRoQ9gyEK/ayhsZksQ1QXdoJ8GU nsNLl4XbqlllvWhYieYNnElAlDS6By3nUqAQkZb6ZqWRGYz1a6k4voqCQVHRl2i/xi QORWoa0l/66N7nKzhJnW3cT3fV9WJf9FKnRguIlRyZB2DwY0EgeY8K3zqq2dGNnU8a Zp9/0Kpx3bCfA== Message-ID: Date: Fri, 20 May 2022 00:41:32 +0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.8.1 Content-Language: en-US To: kernel test robot , Fanjun Kong Cc: Muchun Song , Tejun Heo , Jens Axboe , Linux Kernel Mailing List , Linux Block Mailing List , GNU/Weeb Mailing List , lkp@lists.01.org, lkp@intel.com References: <20220519070506.GA34017@xsang-OptiPlex-9020> From: Ammar Faizi Subject: Re: [blk] 77c570a1ea: WARNING:at_block/blk-cgroup.c:#blkg_create In-Reply-To: <20220519070506.GA34017@xsang-OptiPlex-9020> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit List-Id: Adding the committer, reviewer and acker to the CC list. See the full message here: https://lore.kernel.org/all/20220519070506.GA34017@xsang-OptiPlex-9020/ On 5/19/22 2:05 PM, kernel test robot wrote: > > > Greeting, > > FYI, we noticed the following commit (built with gcc-11): > > commit: 77c570a1ea85ba4ab135c61a028420a6e9fe77f3 ("blk-cgroup: Remove unnecessary rcu_read_lock/unlock()") > https://github.com/ammarfaizi2/linux-block axboe/linux-block/for-next > > in testcase: boot > > on test machine: qemu-system-i386 -enable-kvm -cpu SandyBridge -smp 2 -m 4G > > caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): > > > > If you fix the issue, kindly add following tag > Reported-by: kernel test robot > > > > [ 14.834675][ T1] ------------[ cut here ]------------ > [ 14.835078][ T1] WARNING: CPU: 0 PID: 1 at block/blk-cgroup.c:301 blkg_create+0x39/0x513 This hits the `WARN_ON_ONCE(!rcu_read_lock_held());` in the blkg_create(), here: https://github.com/ammarfaizi2/linux-block/blob/77c570a1ea85ba4ab135c61a028420a6e9fe77f3/block/blk-cgroup.c#L301 > [ 14.835690][ T1] Modules linked in: > [ 14.835984][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.18.0-rc3-00076-g77c570a1ea85 #1 > [ 14.836486][ T1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-4 04/01/2014 > [ 14.836486][ T1] EIP: blkg_create+0x39/0x513 > [ 14.836486][ T1] Code: 89 cb 83 ec 0c 83 05 a0 82 8f d9 01 83 15 a4 82 8f d9 00 e8 a5 be 4c ff 85 c0 75 1e 83 05 a8 82 8f d9 01 83 15 ac 82 8f d9 00 < > 0f> 0b 83 05 b0 82 8f d9 01 83 15 b4 82 8f d9 00 83 3d 58 9d a6 d8 > [ 14.836486][ T1] EAX: 00000000 EBX: f5c26c00 ECX: 00000000 EDX: 00000000 > [ 14.836486][ T1] ESI: f5e4c000 EDI: d98f7280 EBP: c12f5e88 ESP: c12f5e70 > [ 14.836486][ T1] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00010046 > [ 14.836486][ T1] CR0: 80050033 CR2: ffd3a000 CR3: 18d38000 CR4: 000406d0 > [ 14.836486][ T1] Call Trace: > [ 14.836486][ T1] ? _raw_spin_lock_irq+0xba/0xe4 > [ 14.836486][ T1] blkcg_init_queue+0xaf/0x20f > [ 14.836486][ T1] __alloc_disk_node+0x20c/0x3cc > [ 14.836486][ T1] __blk_alloc_disk+0x55/0x97 > [ 14.836486][ T1] brd_alloc+0x1d9/0x393 > [ 14.836486][ T1] ? debugfs_create_dir+0x20/0x17a > [ 14.836486][ T1] brd_init+0x12e/0x1f3 > [ 14.836486][ T1] ? ramdisk_size+0x3d/0x3d > [ 14.836486][ T1] do_one_initcall+0x6f/0x21e > [ 14.836486][ T1] ? lock_is_held+0x19/0x2b > [ 14.836486][ T1] ? rcu_read_lock_sched_held+0x4f/0xb7 > [ 14.836486][ T1] do_initcalls+0x17f/0x1ec > [ 14.836486][ T1] kernel_init_freeable+0x30c/0x3af > [ 14.836486][ T1] ? rest_init+0x2f7/0x2f7 > [ 14.836486][ T1] kernel_init+0x33/0x2ad > [ 14.836486][ T1] ret_from_fork+0x19/0x24 > [ 14.836486][ T1] irq event stamp: 212188 > [ 14.836486][ T1] hardirqs last enabled at (212187): [] __raw_spin_unlock_irqrestore+0x6e/0xf1 > [ 14.836486][ T1] hardirqs last disabled at (212188): [] _raw_spin_lock_irq+0x5f/0xe4 > [ 14.836486][ T1] softirqs last enabled at (210872): [] __do_softirq+0x463/0x4ed > [ 14.836486][ T1] softirqs last disabled at (210863): [] call_on_stack+0x20/0x3a > [ 14.836486][ T1] ---[ end trace 0000000000000000 ]--- -- Ammar Faizi