From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.freebsd.org (mx2.freebsd.org [IPv6:2610:1c1:1:606c::19:2]) by sourceware.org (Postfix) with ESMTPS id 854433840C2C for ; Thu, 9 Jul 2020 16:37:20 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 854433840C2C Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=FreeBSD.org Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=jhb@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits)) (Client CN "mx1.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx2.freebsd.org (Postfix) with ESMTPS id 60D7672243; Thu, 9 Jul 2020 16:37:18 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Received: from smtp.freebsd.org (smtp.freebsd.org [96.47.72.83]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "smtp.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4B2hfQ0VR6z4GTp; Thu, 9 Jul 2020 16:37:18 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Received: from John-Baldwins-MacBook-Pro-274.local (unknown [IPv6:2601:648:8203:2990:a9f0:cdbe:f55:33a7]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client did not present a certificate) (Authenticated sender: jhb) by smtp.freebsd.org (Postfix) with ESMTPSA id 613DD24485; Thu, 9 Jul 2020 16:37:17 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Subject: Re: [PATCH] Don't compare the pid returned from wait() against inferior_ptid. To: Simon Marchi , Gary Benson Cc: Pedro Alves , gdb-patches@sourceware.org References: <20200708004605.91238-1-jhb@FreeBSD.org> <20200708094831.GA9636@blade.nx> <700ffd93-43eb-22c7-b21a-8f4defdd7034@FreeBSD.org> <6891f4e5-7dc3-e2f5-05be-510607ed0485@simark.ca> From: John Baldwin Autocrypt: addr=jhb@FreeBSD.org; keydata= mQGiBETQ+XcRBADMFybiq69u+fJRy/0wzqTNS8jFfWaBTs5/OfcV7wWezVmf9sgwn8TW0Dk0 c9MBl0pz+H01dA2ZSGZ5fXlmFIsee1WEzqeJzpiwd/pejPgSzXB9ijbLHZ2/E0jhGBcVy5Yo /Tw5+U/+laeYKu2xb0XPvM0zMNls1ah5OnP9a6Ql6wCgupaoMySb7DXm2LHD1Z9jTsHcAQMD /1jzh2BoHriy/Q2s4KzzjVp/mQO5DSm2z14BvbQRcXU48oAosHA1u3Wrov6LfPY+0U1tG47X 1BGfnQH+rNAaH0livoSBQ0IPI/8WfIW7ub4qV6HYwWKVqkDkqwcpmGNDbz3gfaDht6nsie5Z pcuCcul4M9CW7Md6zzyvktjnbz61BADGDCopfZC4of0Z3Ka0u8Wik6UJOuqShBt1WcFS8ya1 oB4rc4tXfSHyMF63aPUBMxHR5DXeH+EO2edoSwViDMqWk1jTnYza51rbGY+pebLQOVOxAY7k do5Ordl3wklBPMVEPWoZ61SdbcjhHVwaC5zfiskcxj5wwXd2E9qYlBqRg7QeSm9obiBCYWxk d2luIDxqaGJARnJlZUJTRC5vcmc+iGAEExECACAFAkTQ+awCGwMGCwkIBwMCBBUCCAMEFgID AQIeAQIXgAAKCRBy3lIGd+N/BI6RAJ9S97fvbME+3hxzE3JUyUZ6vTewDACdE1stFuSfqMvM jomvZdYxIYyTUpC5Ag0ERND5ghAIAPwsO0B7BL+bz8sLlLoQktGxXwXQfS5cInvL17Dsgnr3 1AKa94j9EnXQyPEj7u0d+LmEe6CGEGDh1OcGFTMVrof2ZzkSy4+FkZwMKJpTiqeaShMh+Goj XlwIMDxyADYvBIg3eN5YdFKaPQpfgSqhT+7El7w+wSZZD8pPQuLAnie5iz9C8iKy4/cMSOrH YUK/tO+Nhw8Jjlw94Ik0T80iEhI2t+XBVjwdfjbq3HrJ0ehqdBwukyeJRYKmbn298KOFQVHO EVbHA4rF/37jzaMadK43FgJ0SAhPPF5l4l89z5oPu0b/+5e2inA3b8J3iGZxywjM+Csq1tqz hltEc7Q+E08AAwUIAL+15XH8bPbjNJdVyg2CMl10JNW2wWg2Q6qdljeaRqeR6zFus7EZTwtX sNzs5bP8y51PSUDJbeiy2RNCNKWFMndM22TZnk3GNG45nQd4OwYK0RZVrikalmJY5Q6m7Z16 4yrZgIXFdKj2t8F+x613/SJW1lIr9/bDp4U9tw0V1g3l2dFtD3p3ZrQ3hpoDtoK70ioIAjjH aIXIAcm3FGZFXy503DOA0KaTWwvOVdYCFLm3zWuSOmrX/GsEc7ovasOWwjPn878qVjbUKWwx Q4QkF4OhUV9zPtf9tDSAZ3x7QSwoKbCoRCZ/xbyTUPyQ1VvNy/mYrBcYlzHodsaqUDjHuW+I SQQYEQIACQUCRND5ggIbDAAKCRBy3lIGd+N/BCO8AJ9j1dWVQWxw/YdTbEyrRKOY8YZNwwCf afMAg8QvmOWnHx3wl8WslCaXaE8= Message-ID: <37dfa87e-e71b-2357-e140-02f6fd40160c@FreeBSD.org> Date: Thu, 9 Jul 2020 09:37:05 -0700 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <6891f4e5-7dc3-e2f5-05be-510607ed0485@simark.ca> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-3.8 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS, RCVD_IN_DNSWL_LOW, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 09 Jul 2020 16:37:22 -0000 On 7/8/20 9:52 AM, Simon Marchi wrote: > On 2020-07-08 12:46 p.m., John Baldwin wrote: >> On 7/8/20 2:48 AM, Gary Benson wrote: >>> Hi John, >>> >>> John Baldwin wrote: >>>> inf_ptrace::wait() needs to discard termination events reported by >>>> detached child processes. Previously it compared the returned pid >>>> against the pid in inferior_ptid to determine if a termination event >>>> should be discarded or reported. inferior_ptid is now null_ptid in >>>> wait() target methods, so this was always failing and never >>>> reporting exit events. Instead, report termination events whose pid >>>> matches any inferior belonging to the current target. >>>> >>>> gdb/ChangeLog: >>>> >>>> * inf-ptrace.c (inf_ptrace_target::wait): Don't compare against >>>> inferior_ptid. >>> >>> Did the bug you've fixed cause any tests to fail? And, if not, is >>> this something it's possible to write a test for? >> >> It did cause regressions in some tests on FreeBSD. I am still letting >> a before-after testsuite run, but gdb.base/a2-run.exp at least failed >> all tests due to this bug and is back to passing on FreeBSD with the fix. > > Here's the context, for Gary and others: > > https://sourceware.org/pipermail/gdb-patches/2020-July/170238.html > > In the commit message, you should point out that commit xYZ caused some > existing tests to fail, and that this patch makes them pass again. This > way it's implied that there doesn't need to be new tests added, and it > gives a paper trail to understand why this fix has come to be needed. So after some git bisecting on the a2-run.exp test, I found that this actually broke in the multi-target commit. This is ironic as I had tested that change pre-commit and given Pedro patches to fix it on the FreeBSD native target, but clearly I didn't test it well enough. FYI, about 400 tests are fixed on FreeBSD after applying this patch and some other failures go back to failing for an original reason instead of timeouts / GDB internal errors. How's this for an updated log: Don't compare the pid returned from wait() against inferior_ptid. inf_ptrace::wait() needs to discard termination events reported by detached child processes. Previously it compared the returned pid against the pid in inferior_ptid to determine if a termination event should be discarded or reported. The multi-target changes cleared inferior_ptid to null_ptid in wait() target methods, so this was always failing and never reporting exit events. Instead, report termination events whose pid matches any inferior belonging to the current target. Several tests started failing on FreeBSD after the multi-target changes and pass again after this change. -- John Baldwin