From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f200.google.com (mail-pf0-f200.google.com [209.85.192.200]) by kanga.kvack.org (Postfix) with ESMTP id C9EEC6B0069 for ; Mon, 22 Aug 2016 07:43:54 -0400 (EDT) Received: by mail-pf0-f200.google.com with SMTP id h186so191114561pfg.2 for ; Mon, 22 Aug 2016 04:43:54 -0700 (PDT) Received: from szxga01-in.huawei.com (szxga01-in.huawei.com. [58.251.152.64]) by mx.google.com with ESMTPS id p186si22491168pfg.281.2016.08.22.04.43.51 for (version=TLS1 cipher=AES128-SHA bits=128/128); Mon, 22 Aug 2016 04:43:54 -0700 (PDT) Subject: Re: [RFC PATCH v2 2/2] arm64 Kconfig: Select gigantic page References: <1471834603-27053-1-git-send-email-xieyisheng1@huawei.com> <1471834603-27053-3-git-send-email-xieyisheng1@huawei.com> <20160822080358.GF13596@dhcp22.suse.cz> <20160822100045.GA26494@e104818-lin.cambridge.arm.com> From: Yisheng Xie Message-ID: Date: Mon, 22 Aug 2016 19:33:46 +0800 MIME-Version: 1.0 In-Reply-To: <20160822100045.GA26494@e104818-lin.cambridge.arm.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Catalin Marinas , Michal Hocko Cc: mark.rutland@arm.com, linux-mm@kvack.org, sudeep.holla@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, dave.hansen@intel.com, robh+dt@kernel.org, guohanjun@huawei.com, akpm@linux-foundation.org, n-horiguchi@ah.jp.nec.com, linux-arm-kernel@lists.infradead.org, mike.kravetz@oracle.com On 2016/8/22 18:00, Catalin Marinas wrote: > On Mon, Aug 22, 2016 at 10:03:58AM +0200, Michal Hocko wrote: >> On Mon 22-08-16 10:56:43, Xie Yisheng wrote: >>> Arm64 supports gigantic page after >>> commit 084bd29810a5 ("ARM64: mm: HugeTLB support.") >>> however, it got broken by >>> commit 944d9fec8d7a ("hugetlb: add support for gigantic page >>> allocation at runtime") >>> >>> This patch selects ARCH_HAS_GIGANTIC_PAGE to make this >>> function can be used again. >> >> I haven't double checked that the above commit really broke it but if >> that is the case then >> >> Fixes: 944d9fec8d7a ("hugetlb: add support for gigantic page allocation at runtime") >> >> would be nice as well I guess. I do not think that marking it for stable >> is really necessary considering how long it's been broken and nobody has >> noticed... > > I'm not sure that commit broke it. The gigantic functionality introduced > by the above commit was under an #ifdef CONFIG_X86_64. Prior > to that we had a VM_BUG_ON(hstate_is_gigantic(h)). > Hi Catalin and Michal , Thank you for your reply. Before that commit gigantic pages can only be allocated at boottime and can't be freed. That why we had VM_BUG_ON(hstate_is_gigantic(h)) in function update_and_free_page() Prior to that. Anyway, it should not just add #ifdef CONFIG_X86_64 for arm64 already supported 1G hugepage before that commit. Right? Please let me know if I miss something. Thanks Xie Yisheng. -- 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