From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753309Ab3KRCRn (ORCPT ); Sun, 17 Nov 2013 21:17:43 -0500 Received: from mx1.redhat.com ([209.132.183.28]:23203 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751377Ab3KRCRg (ORCPT ); Sun, 17 Nov 2013 21:17:36 -0500 Date: Mon, 18 Nov 2013 10:16:41 +0800 From: Dave Young To: Matt Fleming Cc: linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, x86@kernel.org, mjg59@srcf.ucam.org, hpa@zytor.com, James.Bottomley@HansenPartnership.com, vgoyal@redhat.com, ebiederm@xmission.com, horms@verge.net.au, kexec@lists.infradead.org, bp@alien8.de Subject: Re: [patch 5/7 v2] export efi runtime memory mapping to sysfs Message-ID: <20131118021641.GC4025@dhcp-16-126.nay.redhat.com> References: <20131105082007.872550445@dhcp-16-126.nay.redhat.com> <20131105082718.185728964@dhcp-16-126.nay.redhat.com> <20131113155027.GC17248@console-pimps.org> <20131114015047.GD4081@dhcp-16-126.nay.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20131114015047.GD4081@dhcp-16-126.nay.redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > > +/* > > > + * These are default attributes that are added for every memmap entry. > > > + */ > > > +static struct attribute *def_attrs[] = { > > > + &map_type_attr.attr, > > > + &map_phys_addr_attr.attr, > > > + &map_virt_addr_attr.attr, > > > + &map_num_pages_attr.attr, > > > + &map_attribute_attr.attr, > > > + NULL > > > +}; > > > > If the UEFI spec ever releases an update for the memory descriptor > > structure, and bumps 'memmap.desc_version', how are we going to signal > > the incompatibility to legacy versions of kexec tools? > > Hmm, that is a problem. I will consider to export memmap according to > what firmware provided with extra desc_version instead of using attrs from kernel > data structure efi_memory_desc_t > Matt, desc_version is already in boot_params.efi_info, so kexec-tools can get the version from there. I do not need to export it as another file. I think for now we do not need worry much about the compatibility issue, do you think I need add version checking in kexec-tools currently? like below? if (desc_version != 1) /* current version is 1? */ error out it is not supported -- Thanks Dave From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Young Subject: Re: [patch 5/7 v2] export efi runtime memory mapping to sysfs Date: Mon, 18 Nov 2013 10:16:41 +0800 Message-ID: <20131118021641.GC4025@dhcp-16-126.nay.redhat.com> References: <20131105082007.872550445@dhcp-16-126.nay.redhat.com> <20131105082718.185728964@dhcp-16-126.nay.redhat.com> <20131113155027.GC17248@console-pimps.org> <20131114015047.GD4081@dhcp-16-126.nay.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20131114015047.GD4081-je1gSBvt1TcFLmT5oZ11vB/sF2h8X+2i0E9HWUfgJXw@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+glkk-kexec=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: Matt Fleming Cc: mjg59-1xO5oi07KQx4cg9Nei1l7Q@public.gmane.org, linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, James.Bottomley-d9PhHud1JfjCXq6kfMZ53/egYHeGw8Jk@public.gmane.org, horms-/R6kz+dDXgpPR4JQBCEnsQ@public.gmane.org, bp-Gina5bIWoIWzQB+pC5nmwQ@public.gmane.org, ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org, hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org, vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org List-Id: linux-efi@vger.kernel.org > > > +/* > > > + * These are default attributes that are added for every memmap entry. > > > + */ > > > +static struct attribute *def_attrs[] = { > > > + &map_type_attr.attr, > > > + &map_phys_addr_attr.attr, > > > + &map_virt_addr_attr.attr, > > > + &map_num_pages_attr.attr, > > > + &map_attribute_attr.attr, > > > + NULL > > > +}; > > > > If the UEFI spec ever releases an update for the memory descriptor > > structure, and bumps 'memmap.desc_version', how are we going to signal > > the incompatibility to legacy versions of kexec tools? > > Hmm, that is a problem. I will consider to export memmap according to > what firmware provided with extra desc_version instead of using attrs from kernel > data structure efi_memory_desc_t > Matt, desc_version is already in boot_params.efi_info, so kexec-tools can get the version from there. I do not need to export it as another file. I think for now we do not need worry much about the compatibility issue, do you think I need add version checking in kexec-tools currently? like below? if (desc_version != 1) /* current version is 1? */ error out it is not supported -- Thanks Dave From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([209.132.183.28]) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ViEP6-00010F-HZ for kexec@lists.infradead.org; Mon, 18 Nov 2013 02:17:32 +0000 Date: Mon, 18 Nov 2013 10:16:41 +0800 From: Dave Young Subject: Re: [patch 5/7 v2] export efi runtime memory mapping to sysfs Message-ID: <20131118021641.GC4025@dhcp-16-126.nay.redhat.com> References: <20131105082007.872550445@dhcp-16-126.nay.redhat.com> <20131105082718.185728964@dhcp-16-126.nay.redhat.com> <20131113155027.GC17248@console-pimps.org> <20131114015047.GD4081@dhcp-16-126.nay.redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20131114015047.GD4081@dhcp-16-126.nay.redhat.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" Errors-To: kexec-bounces+dwmw2=twosheds.infradead.org@lists.infradead.org To: Matt Fleming Cc: mjg59@srcf.ucam.org, linux-efi@vger.kernel.org, x86@kernel.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, James.Bottomley@HansenPartnership.com, horms@verge.net.au, bp@alien8.de, ebiederm@xmission.com, hpa@zytor.com, vgoyal@redhat.com > > > +/* > > > + * These are default attributes that are added for every memmap entry. > > > + */ > > > +static struct attribute *def_attrs[] = { > > > + &map_type_attr.attr, > > > + &map_phys_addr_attr.attr, > > > + &map_virt_addr_attr.attr, > > > + &map_num_pages_attr.attr, > > > + &map_attribute_attr.attr, > > > + NULL > > > +}; > > > > If the UEFI spec ever releases an update for the memory descriptor > > structure, and bumps 'memmap.desc_version', how are we going to signal > > the incompatibility to legacy versions of kexec tools? > > Hmm, that is a problem. I will consider to export memmap according to > what firmware provided with extra desc_version instead of using attrs from kernel > data structure efi_memory_desc_t > Matt, desc_version is already in boot_params.efi_info, so kexec-tools can get the version from there. I do not need to export it as another file. I think for now we do not need worry much about the compatibility issue, do you think I need add version checking in kexec-tools currently? like below? if (desc_version != 1) /* current version is 1? */ error out it is not supported -- Thanks Dave _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec