From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.12] helo=sc8-sf-mx2.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1DXzoB-00045R-TA for user-mode-linux-devel@lists.sourceforge.net; Tue, 17 May 2005 04:00:19 -0700 Received: from hirsch.in-berlin.de ([192.109.42.6] ident=root) by sc8-sf-mx2.sourceforge.net with esmtp (TLSv1:AES256-SHA:256) (Exim 4.41) id 1DXzoA-0005m4-5s for user-mode-linux-devel@lists.sourceforge.net; Tue, 17 May 2005 04:00:19 -0700 From: Gerd Knorr Subject: Re: [uml-devel] Re: uml-general-protection-fault even more kludgy but mergeable Message-ID: <20050517105934.GD20584@bytesex> References: <200505170005.43629.blaisorblade@yahoo.it> <20050517100317.GB20584@bytesex> <4289C66C.9000709@fujitsu-siemens.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4289C66C.9000709@fujitsu-siemens.com> 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: Tue, 17 May 2005 12:59:34 +0200 To: Bodo Stroesser Cc: Blaisorblade , Jeff Dike , user-mode-linux-devel@lists.sourceforge.net > >The case I trapped into was an attempt to access I/O ports of a > >process running inside the uml. The uml kernel then tried to > >handle that as page fault, which didn't work very well ... > Unfortunately, I can't find the previous mails about this. So, maybe I'm > totally wrong. If so, please discard this mail. Yes, was discussed quite some time ago, more than half a year IIRC. > Gerd, did you see the problem in SKAS3 on i386? If so, it would be nice to > see what happens in SKAS0. Not tested yet. > I saw similar problems regarding bad LDT-descriptors. Processes using a bad > descriptor loop on page_fault. > > The real fix for this is to add trap_no to the info, that is read from host > by PTRACE_FAULTINFO. With this info, UML can distinguish between real page > faults and other SIGSEGVs. Yes, that conclusion we came to as well, the real fix would be pass on trap_no. The patch mentioned in $subject is a band-aid fix to deal with it a bit better without having the trap number. > In SKAS0, UML already has the full info, as it retrieves the info from a > sigcontext. Then skas0 should do fine in theory ;) Gerd -- -mm seems unusually stable at present. -- akpm about 2.6.12-rc3-mm3 ------------------------------------------------------- This SF.Net email is sponsored by Oracle Space Sweepstakes Want to be the first software developer in space? Enter now for the Oracle Space Sweepstakes! http://ads.osdn.com/?ad_id=7412&alloc_id=16344&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