From owner-freebsd-hackers@FreeBSD.ORG Tue Mar 10 13:39:58 2009 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id D075C1065673 for ; Tue, 10 Mar 2009 13:39:58 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42]) by mx1.freebsd.org (Postfix) with ESMTP id A11DD8FC17 for ; Tue, 10 Mar 2009 13:39:58 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from server.baldwin.cx (pool-98-109-39-197.nwrknj.fios.verizon.net [98.109.39.197]) by cyrus.watson.org (Postfix) with ESMTPSA id 4DC3B46B0D; Tue, 10 Mar 2009 09:39:58 -0400 (EDT) Received: from localhost (john@localhost [127.0.0.1]) (authenticated bits=0) by server.baldwin.cx (8.14.3/8.14.3) with ESMTP id n2ADdYC4026352; Tue, 10 Mar 2009 09:39:52 -0400 (EDT) (envelope-from jhb@freebsd.org) From: John Baldwin To: Alexej Sokolov Date: Tue, 10 Mar 2009 09:31:33 -0400 User-Agent: KMail/1.9.7 References: <671bb5fc0903060813s284673e2t4d3c77b0ed6abc54@mail.gmail.com> <200903091618.32955.jhb@freebsd.org> <671bb5fc0903100316s16c0ae36ocaac3cdab955584d@mail.gmail.com> In-Reply-To: <671bb5fc0903100316s16c0ae36ocaac3cdab955584d@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200903100931.34071.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH authentication, not delayed by milter-greylist-2.0.2 (server.baldwin.cx [127.0.0.1]); Tue, 10 Mar 2009 09:39:52 -0400 (EDT) X-Virus-Scanned: ClamAV 0.94.2/9084/Tue Mar 10 03:11:13 2009 on server.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-4.4 required=4.2 tests=ALL_TRUSTED,AWL,BAYES_00 autolearn=ham version=3.1.3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on server.baldwin.cx Cc: freebsd-hackers@freebsd.org Subject: Re: wrong data in remapped buffer X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 10 Mar 2009 13:39:59 -0000 On Tuesday 10 March 2009 6:16:27 am Alexej Sokolov wrote: > 2009/3/9 John Baldwin > > > On Monday 09 March 2009 3:38:55 pm Alexej Sokolov wrote: > > > 2009/3/9 John Baldwin > > > > > > > On Friday 06 March 2009 11:13:38 am Alexej Sokolov wrote: > > > > > Hello, > > > > > I try to MALLOC a buffer in kern, then remap it with vm_map_find(), > > to > > > > space > > > > > of user process. > > > > > Some times the remapped buffer in user space contain incorrect data. > > > > > > > > What architecture are you using? On some archs like amd64, small > > mallocs > > > > (<= > > > > PAGE_SIZE) don't use the kmem_map or kmem_object. > > > > > > > > -- > > > > John Baldwin > > > > > > > anyway , the error happens only some times... I think there is other > > reason. > > > My hardware is amd64 > > > % uname -ms > > > FreeBSD i386 > > > > i386 always uses kmem for malloc(9). > > > > -- > > John Baldwin > > ok, > and what should be a reason of inconsistent data after remapping ? I don't know off the top of my head. I'm not really sure your use of vm_map_find() is correct, but I don't know it well enough to comment further. -- John Baldwin