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 1EZW1G-0005SU-50 for user-mode-linux-devel@lists.sourceforge.net; Tue, 08 Nov 2005 08:08:22 -0800 Received: from smtp005.mail.ukl.yahoo.com ([217.12.11.36]) by mail.sourceforge.net with smtp (Exim 4.44) id 1EZW1F-0006PO-C6 for user-mode-linux-devel@lists.sourceforge.net; Tue, 08 Nov 2005 08:08:21 -0800 From: Blaisorblade Subject: Re: [uml-devel] [PATCH 8/10] UML - Maintain own LDT entries References: <200510310439.j9V4dfbw000872@ccure.user-mode-linux.org> <200511072028.23111.blaisorblade@yahoo.it> <4370C36E.2040205@fujitsu-siemens.com> In-Reply-To: <4370C36E.2040205@fujitsu-siemens.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200511081702.02891.blaisorblade@yahoo.it> 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, 8 Nov 2005 17:02:02 +0100 To: user-mode-linux-devel@lists.sourceforge.net Cc: Bodo Stroesser , Jeff Dike , linux-kernel@vger.kernel.org, Allan Graves On Tuesday 08 November 2005 16:25, Bodo Stroesser wrote: > Blaisorblade wrote: > > On Monday 07 November 2005 13:20, Bodo Stroesser wrote: > >>Blaisorblade wrote: > >>>On Monday 31 October 2005 05:39, Jeff Dike wrote: > >>>>From: Bodo Stroesser > In my opinion there is no reason to change the current implementation for > SAKS3/0. Note: if someone reads LDT via [sys_]modify_ldt(), he will receive > the requested data in "processor format", that is LDT-descriptors. He will > receive a list of descriptors starting at the first descriptor of the LDT, > thus no entry number is needed in the enties. Ehrr... ACK! You're right, I really _did_ miss the read_ldt case. > The only case that uses user_desc is when writing one desriptor via > modify_ldt(). modify_ldt(WRITE) exactly writes one LDT-descriptor, so > user_desc must contain the number of the entry to write. Thus user_desc is > bigger than LDT descriptor. It also uses an other data layout resulting in > double the size of LDT-descriptor. So I think it doesn't make sense to > store user_desc. We save memory storing the resulting LDT-descriptors, > which then are copied transparently on modify_ldt(READ). Conversion between > user_desc and LDT-entry is done on modify_ldt(WRITE) in SKAS0 only. No > other conversions are done in UML. Ok, I now totally agree with your point. I had missed the read_ldt case. It's perfectly fine to keep it as-is. -- Inform me of my mistakes, so I can keep imitating Homer Simpson's "Doh!". Paolo Giarrusso, aka Blaisorblade (Skype ID "PaoloGiarrusso", ICQ 215621894) http://www.user-mode-linux.org/~blaisorblade ___________________________________ Yahoo! Mail: gratis 1GB per i messaggi e allegati da 10MB http://mail.yahoo.it ------------------------------------------------------- SF.Net email is sponsored by: Tame your development challenges with Apache's Geronimo App Server. Download it for free - -and be entered to win a 42" plasma tv or your very own Sony(tm)PSP. Click here to play: http://sourceforge.net/geronimo.php _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel