From owner-freebsd-mips@freebsd.org Wed Nov 11 14:22:14 2015 Return-Path: Delivered-To: freebsd-mips@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 3AF22A2B0D5 for ; Wed, 11 Nov 2015 14:22:14 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: from hz.grosbein.net (hz.grosbein.net [78.47.246.247]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "hz.grosbein.net", Issuer "hz.grosbein.net" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id A79BD1FE4; Wed, 11 Nov 2015 14:22:12 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: from eg.sd.rdtc.ru (root@eg.sd.rdtc.ru [62.231.161.221]) by hz.grosbein.net (8.14.9/8.14.9) with ESMTP id tABEM1tY002433 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Wed, 11 Nov 2015 15:22:02 +0100 (CET) (envelope-from eugen@grosbein.net) X-Envelope-From: eugen@grosbein.net X-Envelope-To: kostikbel@gmail.com Received: from eg.sd.rdtc.ru (eugen@localhost [127.0.0.1]) by eg.sd.rdtc.ru (8.15.2/8.15.2) with ESMTP id tABELuXU089013; Wed, 11 Nov 2015 21:21:57 +0700 (KRAT) (envelope-from eugen@grosbein.net) Subject: Re: USB-related problem To: Konstantin Belousov References: <563F5630.2000407@grosbein.net> <563F6F6F.1010807@grosbein.net> <563F91A8.9080702@grosbein.net> <5640C0FD.2040803@grosbein.net> <5640F315.5020303@grosbein.net> <20151111120508.GZ2257@kib.kiev.ua> Cc: Jeff Roberson , benno , "freebsd-mips@freebsd.org" From: Eugene Grosbein X-Enigmail-Draft-Status: N1110 Message-ID: <56434F04.9010408@grosbein.net> Date: Wed, 11 Nov 2015 21:21:56 +0700 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:38.0) Gecko/20100101 Thunderbird/38.2.0 MIME-Version: 1.0 In-Reply-To: <20151111120508.GZ2257@kib.kiev.ua> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=0.3 required=5.0 tests=BAYES_00,LOCAL_FROM autolearn=no version=3.3.2 X-Spam-Report: * -2.3 BAYES_00 BODY: Bayes spam probability is 0 to 1% * [score: 0.0000] * 2.6 LOCAL_FROM From my domains X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on hz.grosbein.net X-BeenThere: freebsd-mips@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Porting FreeBSD to MIPS List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 11 Nov 2015 14:22:14 -0000 On 11.11.2015 19:05, Konstantin Belousov wrote: > On Tue, Nov 10, 2015 at 02:25:09AM +0700, Eugene Grosbein wrote: >> On 09.11.2015 22:53, Adrian Chadd wrote: >>> ok, let's get it to hang, then break into ddb and do 'show >>> allthreads', 'show alllocks', 'bufvars' with my vfs_bio.c patch, etc. >> >> I've re-read https://www.freebsd.org/doc/en/books/developers-handbook/kerneldebug-deadlocks.html >> and rebuilt kernel with additional debugging and reproduced the problem again to supply >> more vfs lock info: > > You have syncer running with the buffer arena mutex locked. This probably > means that you have DIAGNOSTIC option turned on, do you ? I do, I've just added it before latest series of my tests because of Handbook instuctions. The problem reproduces without DIAGNOSTICS too. > If yes, set debug.vmem_check to zero, otherwise it just eats your anemic CPU. > > Also, I am curious what is the value of vfs.unmapped_buf_allowed on > your platform. vfs.unmapped_buf_allowed: 0 I've set sysctl debug.vmem_check=0 and repeated the test. The problem reproduced without any changes in my trace.