Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751131AbWIMTRc (ORCPT ); Wed, 13 Sep 2006 15:17:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750937AbWIMTRc (ORCPT ); Wed, 13 Sep 2006 15:17:32 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:29905 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S1751137AbWIMTRb (ORCPT ); Wed, 13 Sep 2006 15:17:31 -0400 Subject: Re: Assignment of GDT entries From: Arjan van de Ven To: Jeremy Fitzhardinge Cc: Linus Torvalds , Ingo Molnar , Andi Kleen , "Eric W. Biederman" , Zachary Amsden , Linux Kernel Mailing List , Michael A Fetterman In-Reply-To: <450854F3.20603@goop.org> References: <450854F3.20603@goop.org> Content-Type: text/plain Organization: Intel International BV Date: Wed, 13 Sep 2006 21:16:41 +0200 Message-Id: <1158175001.3054.7.camel@laptopd505.fenrus.org> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1188 Lines: 37 On Wed, 2006-09-13 at 11:58 -0700, Jeremy Fitzhardinge wrote: > What's the rationale for the current assignment of GDT entries? In > particular, this section: > > * 0 - null > * 1 - reserved > * 2 - reserved > * 3 - reserved > * > * 4 - unused <==== new cacheline > * 5 - unused > * > * ------- start of TLS (Thread-Local Storage) segments: > * > * 6 - TLS segment #1 [ glibc's TLS segment ] > * 7 - TLS segment #2 [ Wine's %fs Win32 segment ] > * 8 - TLS segment #3 > * 9 - reserved > * 10 - reserved > * 11 - reserved > > > What are entries 1-3 and 9-11 reserved for? Must they be unused for > some reason, or is there some proposed use that has not been impemented yet? I don't know the exact details on these; I do know that several GDT entries tend to be used by BIOSes in their APM implementations and thus are better of not being used. That might be the underlying reason here.... - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/