From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cpout1.tiscali.be (cpout1.tiscali.be [62.235.13.193]) by dsl2.external.hp.com (Postfix) with ESMTP id 81298483E for ; Tue, 14 Oct 2003 10:59:55 -0600 (MDT) Date: Tue, 14 Oct 2003 18:59:52 +0200 Message-ID: <3F8A272E0000157A@ocpmta3.freegates.net> In-Reply-To: <20031003114959.GM24824@parcelfarce.linux.theplanet.co.uk> From: "Joel Soete" Subject: Re: [parisc-linux] L2000/N4000 smp devices/boot compare?? To: "Matthew Wilcox" Cc: parisc-linux@parisc-linux.org, "Derek Engelhaupt" MIME-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Sender: parisc-linux-admin@lists.parisc-linux.org Errors-To: parisc-linux-admin@lists.parisc-linux.org List-Help: List-Post: List-Subscribe: , List-Id: parisc-linux developers list List-Unsubscribe: , List-Archive: Hi Matthew, Just comeback to you on this stuff to be sure I well understand :) >> As I try, without any success :(, to find where 'rules for non-coherent >aliases' >> are not respected, I will waiting for a fix. > >Well, it's hard. Consider a page in the page cache. It has a kernel >address and one-or-more user addresses. The user addresses all follow the >coherency rules but the kernel address doesn't. If you look in Appendix F, >we're not allowed to have multiple write-capable translations to the same >address. If I well understand it means that a same real (absolute) address has a different virtual addresse for each processor? >I think the only way to solve this is by (ab)using kmap to ensure that >kernel pages are only accessed via coherent mappings. I find back an interesting info into where it is mentioned 'ping-pong the translations...'. Do you think it could be a solution? (btw Do you have any idea where i can find of the detail way to implement it?) thanks again, Joel ------------------------------------------------------------------------- L'Internet rapide, c'est pour tout le monde. Tiscali ADSL, 19,50 Euro pendant 3 mois! http://reg.tiscali.be/default.asp?lg=fr