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Thu, 16 Jul 2026 06:54:23 +0000 (GMT) Received: from [9.224.77.173] (unknown [9.224.77.173]) by smtpav07.fra02v.mail.ibm.com (Postfix) with ESMTP; Thu, 16 Jul 2026 06:54:22 +0000 (GMT) Message-ID: <758006dc-e6f6-4a37-b864-5e885c52abd3@linux.ibm.com> Date: Thu, 16 Jul 2026 08:54:22 +0200 Precedence: bulk X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] btrfs: fix a lockdep caused by path resolution during device scan To: Qu Wenruo , linux-btrfs@vger.kernel.org References: <49654338e775adb4b40124ea5a3abeb0dc6fdb42.1784027853.git.wqu@suse.com> Content-Language: en-US From: Christian Borntraeger In-Reply-To: <49654338e775adb4b40124ea5a3abeb0dc6fdb42.1784027853.git.wqu@suse.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Spam-Info: AW1haW4tMjYwNzE2MDA2NyBTYWx0ZWRfXwxkdP7zZqg5Y nMYz1pyXCn7gYMV7Ll5nOGA1d37pNphej9kg/YwT+nHccI3nJmhFcgmBOyU6ed1n6xJ72uwCyAV dgbMufPM5XFudMpyVINt2F8NdWF3gDY= X-Authority-Analysis: v=2.4 cv=Mp1iLWae c=1 sm=1 tr=0 ts=6a588022 cx=c_pps a=3Bg1Hr4SwmMryq2xdFQyZA==:117 a=3Bg1Hr4SwmMryq2xdFQyZA==:17 a=IkcTkHD0fZMA:10 a=RAioF0-LDSMA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=uAbxVGIbfxUO_5tXvNgY:22 a=VwQbUJbxAAAA:8 a=VnNF1IyMAAAA:8 a=iox4zFpeAAAA:8 a=YZoY2-2WaaR9FNdqre0A:9 a=QEXdDO2ut3YA:10 a=WzC6qhA0u3u7Ye7llzcV:22 X-Proofpoint-GUID: 3p_8cikTmOWfHKlOhrotWfLo0ndUXc-U X-Proofpoint-ORIG-GUID: 3p_8cikTmOWfHKlOhrotWfLo0ndUXc-U X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNzE2MDA2NyBTYWx0ZWRfX6pbopXXBB3uA c+9EM15P0EDU3L9gox4xV3D1N71J5Dzx4iyYTVfjWqoJwXedhA3DvOMDP8SK5lLiyU8sWa3eE3z R9EiSDlfd4ggvQIvzhBaZqQ7FSMjB2q3jImla65HfRnjrZQ+K0Br+dgGU/MzWQlnnnwdeHvtsBj eUGqu8pkJHZ4aPjQDspr3dYtJGuZxaqbalr6FdO7TUpHaw50U33TgIn6nYcb85CTSzXMeT8Vh2s mEfSX+nmCsD1TVHDg8CW+FAkn+gqPkzXuqCQ+MkCOBHRrnIY95f8ntd6iwU/BNvlBtkpZFL158w kbIU192NB1zmF5Tc+Whgi8XQM1+90HDD/RP4KtLdhdZoQiOh9VtKXngazT6EPgEPZZoQsxtQ4w9 h46ZKMKfnrpd84rsS1sHmYFBRGs5fcRf/6MH2Ja6OvGs5KqPXsYoUqvdkTgRsvOdyyy2I2Ioz1h 6U0GIQvmv6FDNZ6KTew== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-07-16_02,2026-07-15_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 bulkscore=0 spamscore=0 malwarescore=0 lowpriorityscore=0 impostorscore=0 priorityscore=1501 suspectscore=0 clxscore=1015 phishscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2607160067 Am 14.07.26 um 13:17 schrieb Qu Wenruo: > [BUG] > There is a lockdep report related to device scan: > > ====================================================== > WARNING: possible circular locking dependency detected > 7.2.0-20260712.rc2.git0.e3321fa3034d.300.fc44.s390x+debug #1 Not tainted > ------------------------------------------------------ > (udev-worker)/1653 is trying to acquire lock: > 0000006919232220 (&type->i_mutex_dir_key#2){++++}-{3:3}, at: lookup_slow+0x3e/0x70 > but task is already holding lock: > 00000069238564d8 (&fs_devs->device_list_mutex){+.+.}-{3:3}, at: device_list_add.constprop.0+0x148/0xc60 > which lock already depends on the new lock. [...]> > Reported-by: Christian Borntraeger > Link: https://lore.kernel.org/linux-btrfs/5a9d9847-4ae6-43c4-afdc-6e5fa51d6117@linux.ibm.com/ > Fixes: 2e8b6bc0ab41 ("btrfs: avoid unnecessary device path update for the same device") > Signed-off-by: Qu Wenruo Tested-by: Christian Borntraeger I can no longer see the lockdep splat for this chain in our CI logs