From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=mail.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1Eya6l-0006ZP-9w for user-mode-linux-devel@lists.sourceforge.net; Mon, 16 Jan 2006 11:33:39 -0800 Received: from wproxy.gmail.com ([64.233.184.193]) by mail.sourceforge.net with esmtp (Exim 4.44) id 1Eya6k-00050D-RK for user-mode-linux-devel@lists.sourceforge.net; Mon, 16 Jan 2006 11:33:39 -0800 Received: by wproxy.gmail.com with SMTP id i30so1175425wra for ; Mon, 16 Jan 2006 11:33:36 -0800 (PST) Message-ID: <43CBF532.8020103@gmail.com> From: Jacob Bachmeyer Reply-To: jcb62281@gmail.com MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: [uml-devel] SKAS4 design question Sender: user-mode-linux-devel-admin@lists.sourceforge.net Errors-To: user-mode-linux-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: The user-mode Linux development list List-Post: List-Help: List-Subscribe: , List-Archive: Date: Mon, 16 Jan 2006 13:34:10 -0600 To: user-mode-linux-devel@lists.sourceforge.net Cc: jcb62281@gmail.com Has any thought been given to making SKAS4 suitably generic that it could be used for more than just UML? I'm thinking of some arrangement where one process can handle multiple address spaces for multiple other processes. This would have greater application than merely UML--for example, Wine could also be adapted to use SKAS, potentially a killer app, as this could make Wine more secure than Windows. (Running all Wine code in its own address space, separate from the apps Wine runs, could insulate against some application buffer overruns. (due to the way the Win32 API is accessed)) Hmm, what would we need for this to work? --ability to create/release "remote" address spaces --read/write in those "remote" address spaces -- possibly even capability to map a section of a "remote" address space into the control process, do something, then release it --ability to configure pages in a "remote" address space such that accesses trap to the control process --ability to trap all possible syscalls from such an address space for the big bonus: --ability to use either the host scheduler or some code from the not-yet-developed libUML to run threads in the "remote" address spaces Hmm, with a little more effort, this could become a generic compatibility layer for non-Linux programs--for each foreign platform, one would need only a control program that manages the foreign processes and implements the foreign syscalls. {Contemplates HURD on Linux :-)} As I understand it, the Linux mm system is internally moving in this kind of direction already. SKAS would become primarily a system by which pages can have backing store implemented in userspace and "remote" address spaces managed. This direction would certainly help push SKAS into the stock kernel. PS: If I understand correctly, UML with the current SKAS3 works by swapping processes into and out of a single "user" address space. I propose a system where many distinct "user" address spaces are maintained by the kernel and execution is placed whereever the user-mode scheduler says. ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://ads.osdn.com/?ad_id=7637&alloc_id=16865&op=click _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel