From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([66.187.233.31]) by bombadil.infradead.org with esmtp (Exim 4.68 #1 (Red Hat Linux)) id 1Jwp7N-0005qb-UA for kexec@lists.infradead.org; Fri, 16 May 2008 01:52:22 +0000 Date: Thu, 15 May 2008 21:51:42 -0400 From: Vivek Goyal Subject: Re: [PATCH -mm] kexec jump -v9 Message-ID: <20080516015142.GB6926@redhat.com> References: <1204773188.4707.109.camel@caritas-dev.intel.com> <20080514205204.GJ30469@redhat.com> <1210818762.23707.102.camel@caritas-dev.intel.com> <20080515200923.GC9718@redhat.com> <1210902514.23707.161.camel@caritas-dev.intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1210902514.23707.161.camel@caritas-dev.intel.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: kexec-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: "Huang, Ying" Cc: nigel@nigel.suspend2.net, Kexec Mailing List , linux-kernel@vger.kernel.org, "Rafael J. Wysocki" , "Eric W. Biederman" , Pavel Machek , Andrew Morton , linux-pm@lists.linux-foundation.org On Fri, May 16, 2008 at 09:48:34AM +0800, Huang, Ying wrote: > On Thu, 2008-05-15 at 16:09 -0400, Vivek Goyal wrote: > [...] > > Ok, You want to make BIOS calls. We already do that using vm86 mode and > > use bios real mode interrupts. So why do we need this interface? Or, IOW, > > how is this interface better? > > It can call code in 32-bit physical mode in addition to real mode. So It > can be used to call EFI runtime service, especially call EFI 64 runtime > service under 32-bit kernel or vice versa. > > The main purpose of kexec jump is for hibernation. But I think if the > effort is small, why not support general 32-bit physical mode code call > at same time. > In general what's the environment requirements for EFI runtime services? I mean, just that processor should be in protected mode with paging disabled or one need to stop all other cpus and devices and then make the call (as we are doing in this case?). Thanks Vivek _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757227AbYEPBx3 (ORCPT ); Thu, 15 May 2008 21:53:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751074AbYEPBxU (ORCPT ); Thu, 15 May 2008 21:53:20 -0400 Received: from mx1.redhat.com ([66.187.233.31]:59737 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750796AbYEPBxT (ORCPT ); Thu, 15 May 2008 21:53:19 -0400 Date: Thu, 15 May 2008 21:51:42 -0400 From: Vivek Goyal To: "Huang, Ying" Cc: "Eric W. Biederman" , Pavel Machek , nigel@nigel.suspend2.net, "Rafael J. Wysocki" , Andrew Morton , linux-kernel@vger.kernel.org, linux-pm@lists.linux-foundation.org, Kexec Mailing List Subject: Re: [PATCH -mm] kexec jump -v9 Message-ID: <20080516015142.GB6926@redhat.com> References: <1204773188.4707.109.camel@caritas-dev.intel.com> <20080514205204.GJ30469@redhat.com> <1210818762.23707.102.camel@caritas-dev.intel.com> <20080515200923.GC9718@redhat.com> <1210902514.23707.161.camel@caritas-dev.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1210902514.23707.161.camel@caritas-dev.intel.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 16, 2008 at 09:48:34AM +0800, Huang, Ying wrote: > On Thu, 2008-05-15 at 16:09 -0400, Vivek Goyal wrote: > [...] > > Ok, You want to make BIOS calls. We already do that using vm86 mode and > > use bios real mode interrupts. So why do we need this interface? Or, IOW, > > how is this interface better? > > It can call code in 32-bit physical mode in addition to real mode. So It > can be used to call EFI runtime service, especially call EFI 64 runtime > service under 32-bit kernel or vice versa. > > The main purpose of kexec jump is for hibernation. But I think if the > effort is small, why not support general 32-bit physical mode code call > at same time. > In general what's the environment requirements for EFI runtime services? I mean, just that processor should be in protected mode with paging disabled or one need to stop all other cpus and devices and then make the call (as we are doing in this case?). Thanks Vivek