From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.9 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_EF,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dcvr.yhbt.net (Postfix) with ESMTPS id 8BCB31F463 for ; Thu, 19 Sep 2019 08:34:59 +0000 (UTC) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:references:date:in-reply-to :message-id:mime-version:content-type; q=dns; s=default; b=xyJra jw77vhfbgj3zJ37XMWLf2l5WCqdWQ3RO1AWxIVDsaDPGWPJ2laqCo6Kqv64dkWP4 jldCk3EnL5AgIfe+cXDi2MqSM5T2mKcrOay5A+/BVm7juXAoXNqQN18gEqW1JXDa +MEKuBuG/pR7A4YqT7FIfR9Pp7lZ7AqLhSqQbY= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:references:date:in-reply-to :message-id:mime-version:content-type; s=default; bh=dCyMDGpDhgd eAPW8RIp99LJB9Wc=; b=XwYkKSUdpxP4G7bysCLwGdW5QVgf26I+vwG7g8p64Z/ UP0OXi8A5Wz9An4f2JNAU9fn5vZZGYTZ3V6NaiTA3wgmWuI8MOKL4Y2DSr7xp2d6 EiZ5ZGD6G67D6AkZ5l9QXk1DLTBZzNmkHYaSAASGlynHb8hGnWtBb43NRACc6skY = Received: (qmail 82817 invoked by alias); 19 Sep 2019 08:34:57 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Received: (qmail 82807 invoked by uid 89); 19 Sep 2019 08:34:56 -0000 Authentication-Results: sourceware.org; auth=none X-HELO: mx1.suse.de From: Andreas Schwab To: Douglas Jacobsen Cc: libc-alpha@sourceware.org Subject: Re: glibc 2.26 deadlock with __resolv_conf_detach References: X-Yow: I own seven-eighths of all the artists in downtown Burbank! Date: Thu, 19 Sep 2019 10:34:52 +0200 In-Reply-To: (Douglas Jacobsen's message of "Thu, 19 Sep 2019 00:55:00 -0700") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain On Sep 19 2019, Douglas Jacobsen wrote: > The scenario we've uncovered is that some vendor software runs a > multithreaded daemon, which then fork()s, and spawns a thread, In the forked child? If a multi-threaded process calls fork, the child may only call async-signal-safe functions. Andreas. -- Andreas Schwab, SUSE Labs, schwab@suse.de GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7 "And now for something completely different."