From owner-freebsd-stable@FreeBSD.ORG Sun May 20 13:23:37 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id A71801065675 for ; Sun, 20 May 2012 13:23:37 +0000 (UTC) (envelope-from andrey@zonov.org) Received: from mail-bk0-f54.google.com (mail-bk0-f54.google.com [209.85.214.54]) by mx1.freebsd.org (Postfix) with ESMTP id E086A8FC0C for ; Sun, 20 May 2012 13:23:36 +0000 (UTC) Received: by bkvi18 with SMTP id i18so4539699bkv.13 for ; Sun, 20 May 2012 06:23:35 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding :x-gm-message-state; bh=baYuuGEzhSRmBLYlBTT0vEd3dHFpmPr98crCN+fV1QI=; b=MnyoJZAigWSMtlnlioSEMygQDCARisleKo4VTnHTtJ37kFGgmnuFgNoGQPgkeMV2mV jSn2f+ZNcogZLtjn+MWtF9d0rMjRsOUGi/JrF9zRpUOZsF2DcbhBEEbDIfy9o+H4Pksz djDKuNnNRtLCvp3X/Pc4Yvf5OAvkO6pFGiH5tKZx6OIdqNHOXNsNVPA01hhYQ/7Ov631 rF4pBXTWxQPEa82IXYSo/+WOhHCUlL7znbV3qpE7DOYn0wyHgrvKCY6zdiUPFsOaU7oq rK3VCQYvJYC6sW7J4nuTPagcCV75sPNU0H7A6VSyMDJlK2TSQkNgKnclHSnMa3SGMwB+ TxQA== Received: by 10.204.156.150 with SMTP id x22mr6289369bkw.55.1337520215630; Sun, 20 May 2012 06:23:35 -0700 (PDT) Received: from zont-osx.local (ppp95-165-141-253.pppoe.spdop.ru. [95.165.141.253]) by mx.google.com with ESMTPS id e20sm23245058bkw.3.2012.05.20.06.23.34 (version=SSLv3 cipher=OTHER); Sun, 20 May 2012 06:23:35 -0700 (PDT) Message-ID: <4FB8F055.9080700@zonov.org> Date: Sun, 20 May 2012 17:23:33 +0400 From: Andrey Zonov User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: freebsd-stable References: <4FAFEEEF.3040706@zonov.org> <20120513202920.GA18238@dft-labs.eu> <4FB177EE.7030808@zonov.org> In-Reply-To: <4FB177EE.7030808@zonov.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Gm-Message-State: ALoCoQkPkBiPi1XL6u0Y+IAodDGNXPg15WDt0KHtc6exK3pzdWACfWnXV4ycNOUJwK8PLQHHZ6Im Cc: Mateusz Guzik , trasz@freebsd.org Subject: Re: panic with overcommit and RACCT X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 20 May 2012 13:23:37 -0000 On 5/15/12 1:23 AM, Andrey Zonov wrote: > On 5/14/12 12:29 AM, Mateusz Guzik wrote: >> On Sun, May 13, 2012 at 09:27:11PM +0400, Andrey Zonov wrote: >>> Hi, >>> >>> I've got a repeatable panic on latest 9.0-STABLE and HEAD with >>> turned on overcommit (vm.overcommit=1) and RACCT. >>> >>> kgdb trace on today's HEAD: >>> >>> #10 0xffffffff80bc3513 in calltrap () >>> at /usr/src/sys/amd64/amd64/exception.S:228 >>> #11 0xffffffff808aab71 in racct_set_locked (p=0xfffffe0005d684a0, >>> resource=0, >>> amount=2680) at /usr/src/sys/kern/kern_racct.c:372 >>> #12 0xffffffff808ab645 in racct_proc_exit (p=0xfffffe0005d684a0) >>> at /usr/src/sys/kern/kern_racct.c:615 >>> #13 0xffffffff80880d69 in fork1 (td=0xfffffe0005b2c460, flags=20, >>> pages=4, >>> procp=0xffffff811a36bb00, procdescp=Variable "procdescp" is not >>> available. >>> ) at /usr/src/sys/kern/kern_fork.c:943 >>> #14 0xffffffff80882362 in sys_fork (td=0xfffffe0005b2c460, >>> uap=Variable "uap" is not available. >>> ) >>> at /usr/src/sys/kern/kern_fork.c:110 >>> #15 0xffffffff80bd7a89 in amd64_syscall (td=0xfffffe0005b2c460, >>> traced=0) >>> at subr_syscall.c:135 >>> #16 0xffffffff80bc37f7 in Xfast_syscall () >>> at /usr/src/sys/amd64/amd64/exception.S:387 >>> #17 0x00000008024729fc in ?? () >>> Previous frame inner to this frame (corrupt stack?) >>> (kgdb) >>> >>> Unread portion of the kernel message buffer: >>> Kernel page fault with the following non-sleepable locks held: >>> exclusive sleep mutex racct lock (racct lock) r = 0 >>> (0xffffffff8128a7c0) locked @ /usr/src/sys/kern/kern_racct.c:614 >>> exclusive sleep mutex process lock (process lock) r = 0 >>> (0xfffffe0005d68598) locked @ /usr/src/sys/kern/kern_racct.c:603 >>> >> >> It looks like racct_proc_exit can be called for processes without >> properly initialized racct structure, which in turn results in this >> panic. >> >> Can you please test this patch: >> http://student.agh.edu.pl/~mjguzik/patches/racct-fork.patch >> >> ? >> >> I was unable to reproduce panic you describe, so it was tested only by >> manually injecting error. Nevertheless I think you should try it. :) >> > > Thanks, your patch fixes the panic. Can anyone commit this fix? > > How to repeat: > 1. add options RACCT and options RCTL to kernel config, rebuild and > install kernel, reboot > 2. set sysctl vm.overcommit=1 > 3. run as none root something that eats memory (I just run malloc() > until it returns NULL) > 4. swapoff -a > 5. panic after sometime > > With patch applied instead of panic I got: "fork: Cannot allocate > memory". Looks like a bug in overcommit code. > -- Andrey Zonov