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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 51905C54FCC for ; Tue, 21 Apr 2020 15:02:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2A96F206D6 for ; Tue, 21 Apr 2020 15:02:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728802AbgDUPCs (ORCPT ); Tue, 21 Apr 2020 11:02:48 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:54438 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726628AbgDUPCr (ORCPT ); Tue, 21 Apr 2020 11:02:47 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out03.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jQuQA-0003ce-To; Tue, 21 Apr 2020 09:02:46 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jQuQ8-0006pm-IY; Tue, 21 Apr 2020 09:02:46 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Christof Meerwald Cc: linux-kernel@vger.kernel.org References: <20200419201336.GI22017@edge.cmeerw.net> Date: Tue, 21 Apr 2020 09:59:39 -0500 In-Reply-To: <20200419201336.GI22017@edge.cmeerw.net> (Christof Meerwald's message of "Sun, 19 Apr 2020 22:13:36 +0200") Message-ID: <87v9ls51gk.fsf@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-XM-SPF: eid=1jQuQ8-0006pm-IY;;;mid=<87v9ls51gk.fsf@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX19wSpoVnHs/NK3Cbc2PgMStLu6JhH5zp24= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: Re: SIGCHLD signal sometimes sent with si_pid==0 (Linux 5.6.5) X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Christof Meerwald writes: > Hi, > > this is probably related to commit > 7a0cf094944e2540758b7f957eb6846d5126f535 (signal: Correct namespace > fixups of si_pid and si_uid). > > With a 5.6.5 kernel I am seeing SIGCHLD signals that don't include a > properly set si_pid field - this seems to happen for multi-threaded > child processes. Christof I want to say very good spotting and reporting of this issue. Thank you. Eric