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Mon, 14 Feb 2022 16:03:25 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2DB4BA4053; Mon, 14 Feb 2022 16:03:25 +0000 (GMT) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0A645A4051; Mon, 14 Feb 2022 16:03:25 +0000 (GMT) Received: from tuxmaker.linux.ibm.com (unknown [9.152.85.9]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Mon, 14 Feb 2022 16:03:24 +0000 (GMT) From: Sven Schnelle To: David Hildenbrand Cc: linux-kernel@vger.kernel.org Subject: Re: circular locking splat in fs/proc/vmcore.c References: <0a85d63e-8f51-4aaf-1b8e-c323f496cba7@redhat.com> Date: Mon, 14 Feb 2022 17:03:24 +0100 In-Reply-To: <0a85d63e-8f51-4aaf-1b8e-c323f496cba7@redhat.com> (David Hildenbrand's message of "Mon, 14 Feb 2022 16:58:27 +0100") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) Content-Type: text/plain X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: c27dwlktdBQpBn6wvr3xwSwFUtM4Mho3 X-Proofpoint-GUID: 8yg2acYL8jddokAjjEqE1u06H5B0pLEg X-Proofpoint-UnRewURL: 0 URL was un-rewritten MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.816,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2022-02-14_07,2022-02-14_03,2021-12-02_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=810 bulkscore=0 adultscore=0 spamscore=0 priorityscore=1501 mlxscore=0 suspectscore=0 impostorscore=0 malwarescore=0 clxscore=1015 phishscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2201110000 definitions=main-2202140094 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RDNS_NONE, SPF_HELO_NONE,T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi David, David Hildenbrand writes: > On 14.02.22 16:22, Sven Schnelle wrote: >> I think we could also switch the list to an rcu protected list, but i >> don't know the code really. Any opinions how to fix this? >> > did you stumble over > > https://lkml.kernel.org/r/20220119193417.100385-1-david@redhat.com > > yet? > > It should be fixing the (mostly impossible to trigger) splat you've seen > -- via sleepable rcu :) > > The fix is scheduled for v5.18. No, i missed that. Thank you very much! /Sven