From owner-svn-src-all@FreeBSD.ORG Thu Apr 23 18:56:56 2015 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 43DBDBE2 for ; Thu, 23 Apr 2015 18:56:56 +0000 (UTC) Received: from nm14-vm10.bullet.mail.gq1.yahoo.com (nm14-vm10.bullet.mail.gq1.yahoo.com [98.136.218.186]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 131141520 for ; Thu, 23 Apr 2015 18:56:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1429814992; bh=lz1Da5b/edlLLOHid6gbr9ijTz1FoXw2BgsG8g739sU=; h=Subject:From:In-Reply-To:Date:Cc:References:To:From:Subject; b=lzRz8snVFXhH+5Pes0jL1DCGiB/hJ+8euUkLau3FZT0p29Zzyg8bMXAcf33yFqIpQiULEG85UqWErS2ydky/2VfT+GYLigJg5VANmlPG5/NWXJ4u6ERuw4AvXZilISyd6FLtOGBqwf3IzbDI46cQ9lK4nqaL1FtP4nnvjk6TbsstswWHgY+EczuE/iGGbp74+0rK3uKOiqbkCMagzoKQK2LkRjPxhv1+6tmoEOY7B5W3ry99OKOL3LXlDeBXye9XmdSiJ4peZXYEqMxz9mhxmuy+1SEjRH5ynB7oJL08LNsMMS1uknixMkUNHRkqm74YWMR8He8eP4WVy99Avuqjdg== Received: from [98.137.12.61] by nm14.bullet.mail.gq1.yahoo.com with NNFMP; 23 Apr 2015 18:49:52 -0000 Received: from [98.136.164.67] by tm6.bullet.mail.gq1.yahoo.com with NNFMP; 23 Apr 2015 18:49:52 -0000 Received: from [127.0.0.1] by smtp229.mail.gq1.yahoo.com with NNFMP; 23 Apr 2015 18:49:52 -0000 X-Yahoo-Newman-Id: 532243.9751.bm@smtp229.mail.gq1.yahoo.com X-Yahoo-Newman-Property: ymail-3 X-YMail-OSG: Qqlf0.IVM1lICLnaEt3QOieQLHst7rMLH6hsUniG8M9btP6 4caWCJE9rdYDnRNPU8Dwddw2GH7C7BlgsXBzDE_SC6dE5UiCkpkaPiiuw8Pr po.BsywCAUftexncpUhHeJCZL964ZNwT.fLlNdCi8M5lOHwWJFqCkkOoHIVr bOrivGLIevjhEUIS.g7Bgc8.FB8nyAxiQDxyA24E5pD4JptVP8o0nNxxO9yx gBh98YtqeEM7KTC8iAvyTBCzuvodtD7Ov5DOXTRpjOi0fWMpGWrSzf7wioPp 5jK9qJ6QaSRV6w5vemfkjo4oA8851.Y4lqd8iaZww.7qXI008vGHY4r0WYYR zG_D34VIov.HerglUnHz_1TU9HjxBaTIFm8hREsSVz7kJ83hIcMQ.rCu6gN. S_GApKUDP8UCeLVo_MuXle0pSed8ljK6EW1Ebc.EUzrBO60Vi4kIyBTDp3MT sFIeaegHQ1WBGRCjxeWjrV43m2q1NO9AvbIc.oi_esVrf85fnJlWS2jrSQ2G spPjCGwUeqBt77fVUdzOTvsGm3EWQX3lyoflA0WNm X-Yahoo-SMTP: clhABp.swBB7fs.LwIJpv3jkWgo2NU8- Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) Subject: Re: svn commit: r281451 - head/sys/vm From: Scott Long In-Reply-To: <5B48434B-EA97-45B3-BC4E-B039A868186B@yahoo.com> Date: Thu, 23 Apr 2015 12:49:51 -0600 Cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Content-Transfer-Encoding: quoted-printable Message-Id: <4E109480-FD27-4C7F-8B5F-B1DB2232CD3D@yahoo.com> References: <201504120621.t3C6LxAV095209@svn.freebsd.org> <5B48434B-EA97-45B3-BC4E-B039A868186B@yahoo.com> To: Dmitry Chagin X-Mailer: Apple Mail (2.2070.6) X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 23 Apr 2015 18:56:56 -0000 > On Apr 23, 2015, at 6:19 AM, Scott Long wrote: >=20 >>=20 >> On Apr 12, 2015, at 12:21 AM, Dmitry Chagin = wrote: >>=20 >> Author: dchagin >> Date: Sun Apr 12 06:21:58 2015 >> New Revision: 281451 >> URL: https://svnweb.freebsd.org/changeset/base/281451 >>=20 >> Log: >> Rework r281162. Indeed, the flexible array member is preferable here. >>=20 >> Suggested by: Justin T. Gibbs >>=20 >> MFC after: 3 days >>=20 >> Modified: >> head/sys/vm/uma_core.c >> head/sys/vm/uma_int.h >=20 > There=E2=80=99s still something wrong with this. I have a machine = with 28 cores (56 with hyperthreading) and 256GB of RAM, and ever since = you committed r281162, it panics early in boot with a failed assertion. = It looks like the first few members of a uma_slab_t are getting = overwritten accidentally, and somehow the padding of the extra member in = the uma_zone_t was previously protecting it. I don=E2=80=99t know the = exact cause yet, but I must ask that you revert to r281161 in HEAD and = stable/10 until the problem is resolved. >=20 I think the problem is that the masterzone_k and masterzone_z objects = that are statically allocated in uma_core.c no longer have space for the = uz_cpu field, but uma_zalloc_arg() always assumes that it=E2=80=99s = there. Early in boot when the =E2=80=98kegs' and =E2=80=98zones=E2=80=99 = zones are being initialized, there=E2=80=99s only 1 CPU so = pre-allocating 1 uz_cpu element in the uma_zone is enough. I can=E2=80=99= t see any way around this without significantly changing how = uma_zalloc_arg() treats per-cpu caches. I think it=E2=80=99s best to = revert this change. Scott