Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751841AbWHUKT1 (ORCPT ); Mon, 21 Aug 2006 06:19:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751842AbWHUKT1 (ORCPT ); Mon, 21 Aug 2006 06:19:27 -0400 Received: from ns2.suse.de ([195.135.220.15]:61900 "EHLO mx2.suse.de") by vger.kernel.org with ESMTP id S1751841AbWHUKT0 (ORCPT ); Mon, 21 Aug 2006 06:19:26 -0400 From: Andi Kleen To: Magnus Damm Subject: Re: [PATCH][RFC] x86_64: Reload CS when startup_64 is used. Date: Mon, 21 Aug 2006 12:19:09 +0200 User-Agent: KMail/1.9.3 Cc: fastboot@lists.osdl.org, linux-kernel@vger.kernel.org, ebiederm@xmission.com References: <20060821095328.3132.40575.sendpatchset@cherry.local> In-Reply-To: <20060821095328.3132.40575.sendpatchset@cherry.local> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200608211219.09042.ak@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 794 Lines: 25 > > + /* Reload CS with a value that is within our GDT. We need to do this > + * if we were loaded by a 64 bit bootloader that happened to use a > + * CS that is larger than the GDT limit. This is true if we came here > + * from kexec running under Xen. > + */ > + movq %rsp, %rdx > + movq $__KERNEL_DS, %rax > + pushq %rax /* SS */ > + pushq %rdx /* RSP */ > + movq $__KERNEL_CS, %rax > + movq $cs_reloaded, %rdx > + pushq %rax /* CS */ > + pushq %rdx /* RIP */ > + lretq Can't you just use a normal far jump? That might be simpler. -Andi - 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/