From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f47.google.com (mail-pa0-f47.google.com [209.85.220.47]) by kanga.kvack.org (Postfix) with ESMTP id 7A88D82F64 for ; Wed, 21 Oct 2015 14:17:13 -0400 (EDT) Received: by pacfv9 with SMTP id fv9so64014150pac.3 for ; Wed, 21 Oct 2015 11:17:13 -0700 (PDT) Received: from mga14.intel.com (mga14.intel.com. [192.55.52.115]) by mx.google.com with ESMTP id pn6si14993667pbb.43.2015.10.21.11.17.12 for ; Wed, 21 Oct 2015 11:17:12 -0700 (PDT) From: "Luck, Tony" Subject: RE: [PATCH] mm: Introduce kernelcore=reliable option Date: Wed, 21 Oct 2015 18:17:06 +0000 Message-ID: <3908561D78D1C84285E8C5FCA982C28F32B5A060@ORSMSX114.amr.corp.intel.com> References: <1444915942-15281-1-git-send-email-izumi.taku@jp.fujitsu.com> In-Reply-To: <1444915942-15281-1-git-send-email-izumi.taku@jp.fujitsu.com> Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Taku Izumi , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" Cc: "qiuxishi@huawei.com" , "kamezawa.hiroyu@jp.fujitsu.com" , "mel@csn.ul.ie" , "akpm@linux-foundation.org" , "Hansen, Dave" , "matt@codeblueprint.co.uk" + if (reliable_kernelcore) { + for_each_memblock(memory, r) { + if (memblock_is_mirror(r)) + continue; Should we have a safety check here that there is some mirrored memory? If = you give the kernelcore=3Dreliable option on a machine which doesn't have any mirror= configured, then we'll mark all memory as removable. What happens then? Do kernel all= ocations fail? Or do they fall back to using removable memory? Is there a /proc or /sys file that shows the current counts for the removab= le zone? I just tried this patch with a high percentage of memory marked as mirror ... but = I'd like to see how much is actually being used to tune things a bit. -Tony -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org