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: AS53758 23.128.96.0/24 X-Spam-Status: No, score=-4.2 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by dcvr.yhbt.net (Postfix) with ESMTP id CB9C61F8C6 for ; Wed, 15 Sep 2021 20:08:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229732AbhIOUKB (ORCPT ); Wed, 15 Sep 2021 16:10:01 -0400 Received: from pb-smtp1.pobox.com ([64.147.108.70]:64960 "EHLO pb-smtp1.pobox.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231559AbhIOUKA (ORCPT ); Wed, 15 Sep 2021 16:10:00 -0400 Received: from pb-smtp1.pobox.com (unknown [127.0.0.1]) by pb-smtp1.pobox.com (Postfix) with ESMTP id 25544E72AE; Wed, 15 Sep 2021 16:08:41 -0400 (EDT) (envelope-from junio@pobox.com) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; s=sasl; bh=ccHDeEdXBbWpXUXgHixw+mQ7tYa8aXWgrU60Fp 3aof8=; b=q9lT8vwFRwlkGqCrwl5vHkkaADj0xqiFfMkxthwgfptAs9bA1EEA32 nGzzBuxqw5JT1iwsvPoiI3ZVKU5tq+UOA4RX348olg0eWGNFaFBfV2MqHOScLf4t ibzK4CcwoyJpIjjg7cP4YtjbHVUx78EkGiESwoHAYwOdkBrmG0y9M= Received: from pb-smtp1.nyi.icgroup.com (unknown [127.0.0.1]) by pb-smtp1.pobox.com (Postfix) with ESMTP id 1B6FBE72AC; Wed, 15 Sep 2021 16:08:41 -0400 (EDT) (envelope-from junio@pobox.com) Received: from pobox.com (unknown [34.73.10.127]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by pb-smtp1.pobox.com (Postfix) with ESMTPSA id 85703E72AB; Wed, 15 Sep 2021 16:08:40 -0400 (EDT) (envelope-from junio@pobox.com) From: Junio C Hamano To: Jeff King Cc: Patrick Steinhardt , git@vger.kernel.org Subject: Re: [PATCH] t1400: avoid SIGPIPE race condition on fifo References: <1e9e62a2c5f74db91aaded83783076c28b757836.1630659922.git.ps@pks.im> Date: Wed, 15 Sep 2021 13:08:39 -0700 In-Reply-To: (Jeff King's message of "Wed, 15 Sep 2021 13:24:52 -0400") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Pobox-Relay-ID: B8424524-1660-11EC-B903-62A2C8D8090B-77302942!pb-smtp1.pobox.com Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Jeff King writes: > On Wed, Sep 15, 2021 at 01:13:25PM -0400, Jeff King wrote: > >> I think this test may be racy. I saw a strange failure from it in CI: >> >> https://github.com/peff/git/runs/3605506649?check_suite_focus=true#step:5:6734 >> >> I can't reproduce the problem locally with "--stress", but the failure >> there is on macOS (and likewise, a nearby run failed with a timeout just >> for macOS, which could be caused by a racy deadlock). > > Ah, I just wasn't trying hard enough. Using --run=1,190 lets it run a > lot more tightly, and I got a failure pretty quickly. Here's the fix (on > top of ps/update-ref-batch-flush). > > -- >8 -- > Subject: [PATCH] t1400: avoid SIGPIPE race condition on fifo > > t1400.190 sometimes fails or even hangs because of the way it uses > fifos. Our goal is to interactively read and write lines from > update-ref, so we have two fifos, in and out. We open a descriptor > connected to "in" and redirect output to that, so that update-ref does > not see EOF as it would if we opened and closed it for each "echo" call. Thanks. I think I see the same breakage in last night's pushout of 'seen'. Will queue.