From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_HIGH autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5F485C5CFEB for ; Wed, 11 Jul 2018 21:36:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0EDAC2146E for ; Wed, 11 Jul 2018 21:36:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="zwbwhA08" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0EDAC2146E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390325AbeGKVmw (ORCPT ); Wed, 11 Jul 2018 17:42:52 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:59120 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732861AbeGKVmv (ORCPT ); Wed, 11 Jul 2018 17:42:51 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w6BLXVhI051059; Wed, 11 Jul 2018 21:36:20 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : to : references : from : message-id : date : mime-version : in-reply-to : content-type : content-transfer-encoding; s=corp-2018-07-02; bh=dA7RmU3n/xhmHIHGusZnXpIV4gJn7NSiOoV4o9pfMJM=; b=zwbwhA08ma81dgwQxkLUiXZs3wHmWuJQ/BOmp3CsWNr5t0DcOPqlzidnVPhH8iuTM+NQ eFAxb9LRh/avahIO4hXP+fJtB6GSL7Og2e43Ogajkfl+xqMQ5oR56loQ8qfQR8Pf4C8g P2HYr+9nhLe/AMZCPsLj9+1xxlPUHZe6KtmpkP31xvA+F+ChIr7O45ZOK2VftK0lOU2K 3UwYPQjj5fLt98sloWm9vlAjFDiGcNmCs3kBzBxQ2WMP0dHN4MCmz+VXKp+eD7u1426/ GEX3ZAJX8tOlPTs2Y/m2xYPypNAY6viLVgsgV1NekW0YLdcmKzJkFQVVHVyxJtOlcs5r mQ== Received: from aserv0022.oracle.com (aserv0022.oracle.com [141.146.126.234]) by userp2130.oracle.com with ESMTP id 2k2p76817j-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 11 Jul 2018 21:36:20 +0000 Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by aserv0022.oracle.com (8.14.4/8.14.4) with ESMTP id w6BLaJBM004120 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 11 Jul 2018 21:36:19 GMT Received: from abhmp0017.oracle.com (abhmp0017.oracle.com [141.146.116.23]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id w6BLaIxN015174; Wed, 11 Jul 2018 21:36:18 GMT Received: from [192.168.1.164] (/50.38.38.67) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 11 Jul 2018 14:36:18 -0700 Subject: Re: [PATCH] mm/hugetlb: remove gigantic page support for HIGHMEM To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Aneesh Kumar K . V" , Michael Ellerman , Benjamin Herrenschmidt , Michal Hocko , Cannon Matthews , Andrew Morton References: <20180711195913.1294-1-mike.kravetz@oracle.com> <20180711205702.d4xeu552xgxjbse3@linux-r8p5> From: Mike Kravetz Message-ID: Date: Wed, 11 Jul 2018 14:36:16 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <20180711205702.d4xeu552xgxjbse3@linux-r8p5> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8951 signatures=668706 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=2 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1806210000 definitions=main-1807110228 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/11/2018 01:57 PM, Davidlohr Bueso wrote: > On Wed, 11 Jul 2018, Mike Kravetz wrote: > >> This reverts commit ee8f248d266e ("hugetlb: add phys addr to struct >> huge_bootmem_page") >> >> At one time powerpc used this field and supporting code. However that >> was removed with commit 79cc38ded1e1 ("powerpc/mm/hugetlb: Add support >> for reserving gigantic huge pages via kernel command line"). >> >> There are no users of this field and supporting code, so remove it. > > Considering the title, don't you wanna also get rid of try_to_free_low() > and something like the following, which I'm sure can be done fancier, and > perhaps also thp? Not really. The intention is to only remove gigantic huge page support for HIGHMEN systems. Non-gigantic huge pages on HIGHMEN systems should still work/be supported. So, we do not want to make the config change or get rid of try_to_free_low(). Actually, I simply wanted to revert the specific patch which enabled gigantic huge pages on HIGHMEM systems. I did see that check in try_to_free_low(), if (hstate_is_gigantic(h)) return; and considered for a minute turning that into a VM_BUG or WARN, but decided to leave it as is. Do you think the title should be changed to simply 'revert commit ee8f248d266e'? -- Mike Kravetz > diff --git a/fs/Kconfig b/fs/Kconfig > index ac474a61be37..849da70e35d6 100644 > --- a/fs/Kconfig > +++ b/fs/Kconfig > @@ -192,8 +192,8 @@ config TMPFS_XATTR > > config HUGETLBFS > bool "HugeTLB file system support" > - depends on X86 || IA64 || SPARC64 || (S390 && 64BIT) || \ > - SYS_SUPPORTS_HUGETLBFS || BROKEN > + depends on !HIGHMEM && (X86 || IA64 || SPARC64 || (S390 && 64BIT) || \ > + SYS_SUPPORTS_HUGETLBFS || BROKEN) > help > hugetlbfs is a filesystem backing for HugeTLB pages, based on > ramfs. For architectures that support it, say Y here and read > > Thanks, > Davidlohr