From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from out02.mta.xmission.com ([166.70.13.232]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1U0g9j-0002kt-NY for kexec@lists.infradead.org; Wed, 30 Jan 2013 22:29:24 +0000 From: ebiederm@xmission.com (Eric W. Biederman) References: <1358866935-18458-1-git-send-email-trenn@suse.de> <201301301713.43946.trenn@suse.de> <4dc77552-977d-4761-860e-afdec61c4317@email.android.com> <201301301739.52358.trenn@suse.de> <51094FD5.2070909@zytor.com> <87obg6sdtv.fsf@xmission.com> <510992C7.2050000@zytor.com> <877gmumizr.fsf@xmission.com> <51099A3E.5090705@zytor.com> Date: Wed, 30 Jan 2013 14:29:04 -0800 In-Reply-To: <51099A3E.5090705@zytor.com> (H. Peter Anvin's message of "Wed, 30 Jan 2013 14:10:06 -0800") Message-ID: <87ehh2l2z3.fsf@xmission.com> MIME-Version: 1.0 Subject: Re: [PATCH 0/3] Cleanup kdump memmap= passing and e820 usage 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: "H. Peter Anvin" Cc: x86@kernel.org, kexec@lists.infradead.org, Simon Horman , yinghai@kernel.org, Thomas Renninger , vgoyal@redhat.com "H. Peter Anvin" writes: > On 01/30/2013 01:57 PM, Eric W. Biederman wrote: >>> >>> Yes, those seem to be the options, and we're currently discussing which one. >>> >>> The second seems to make more sense to me. The kexec tools build the >>> memory map anyway, and it makes sense to me at least to just build a >>> memory map with the appropriate regions marked as a dumpable type. >> >> This dumpable type doesn't make sense to me. Are you suggesting making >> regions that are memory but that we should not use a special memory >> type? > > Yes. > >> I think I would prefer that to call that new type RESERVED_MEM or >> RESERVED_CACHABLE. Being more specific is fine but dumpable certainly >> doesn't bring to mind what we are saying. Especially since we already >> communicate which areas were memory to the last kernel in an >> architecture generic format. > > I was thinking that marking them differently might help debugging, at > least, but yes, we can have a RESERVED_MEM type. > > However, Thomas does have a point that the current use of fairly small > positive values for Linux-defined types is a bad idea. We should use > negative types, or at least something north of 0x40000000 or so. Yes. It doesn't much matter in the kernel but when it because part of the ABI it is a real issue. Since old kernels treat any value they don't understand as reserved passing a modified e820 map seems reasonable to me once we have reserved a special linux value for it. Eric _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec