From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-5.5 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI,RP_MATCHES_RCVD shortcircuit=no autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 559DE1FF40 for ; Wed, 30 Nov 2016 23:32:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757283AbcK3XcI (ORCPT ); Wed, 30 Nov 2016 18:32:08 -0500 Received: from cloud.peff.net ([104.130.231.41]:49350 "EHLO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757153AbcK3XcH (ORCPT ); Wed, 30 Nov 2016 18:32:07 -0500 Received: (qmail 24917 invoked by uid 109); 30 Nov 2016 23:32:07 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.84) with SMTP; Wed, 30 Nov 2016 23:32:07 +0000 Received: (qmail 26827 invoked by uid 111); 30 Nov 2016 23:32:42 -0000 Received: from sigill.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.7) by peff.net (qpsmtpd/0.84) with SMTP; Wed, 30 Nov 2016 18:32:42 -0500 Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Wed, 30 Nov 2016 18:32:04 -0500 Date: Wed, 30 Nov 2016 18:32:04 -0500 From: Jeff King To: Brandon Williams Cc: Junio C Hamano , git@vger.kernel.org Subject: Re: What's cooking in git.git (Nov 2016, #06; Mon, 28) Message-ID: <20161130233204.ihbrjwwu3yiv4ugq@sigill.intra.peff.net> References: <20161129010538.GA121643@google.com> <20161129063759.6mgmpqx3kbyuqjwi@sigill.intra.peff.net> <20161129065125.cwlbkctniy7oshj2@sigill.intra.peff.net> <20161130195427.GA166433@google.com> <20161130232823.GA192901@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20161130232823.GA192901@google.com> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Wed, Nov 30, 2016 at 03:28:23PM -0800, Brandon Williams wrote: > So I couldn't find a race condition in the code. I tracked the problem > to grep_source_load_file which attempts to run lstat on the file so that > it can read it into a buffer. The lstat call fails with ENOENT (which > conveniently is skipped by the if statement which calls error_errno). So > for some reason the file cannot be found and read into memory resulting > in nothing being grep'ed for that particular file (since the buffer is > NULL). That's definitely weird. Is it possible that any of the underlying calls from another thread are using chdir()? I think realpath() make do that behind the scenes, and there may be others. A full strace from a failing case would be interesting reading. In theory we should be able to get that by running the stress script for long enough. :) -Peff