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=-7.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 CB471C433E0 for ; Sat, 20 Feb 2021 09:03:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A734964ED7 for ; Sat, 20 Feb 2021 09:03:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229806AbhBTJDG (ORCPT ); Sat, 20 Feb 2021 04:03:06 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:57472 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229819AbhBTJCu (ORCPT ); Sat, 20 Feb 2021 04:02:50 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1613811684; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JgoL6yAU+V/ArfjxO3XDCSurXdtNKbGCFrJc0uCVVRc=; b=Eqny4QLbWroe99WbRgPEczS3QxqJ6zCAmUpNo1NVkWpylk1yb1153M2AwyqGLFwHRNsTQf eA1KfWdtP8TwzdO2suo6ileRW0Q8tMarqtNJW8zV94w32FRI0IJbW4GQbiHXRScqNwojOx LYdJVkdm9OrluYJgh+ww3fR+M+6jL7o= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-527-EtcmsycmMP6Ck3kTppQAqg-1; Sat, 20 Feb 2021 04:01:20 -0500 X-MC-Unique: EtcmsycmMP6Ck3kTppQAqg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 91037107ACE3; Sat, 20 Feb 2021 09:01:16 +0000 (UTC) Received: from [10.36.112.45] (ovpn-112-45.ams2.redhat.com [10.36.112.45]) by smtp.corp.redhat.com (Postfix) with ESMTP id 60B415D9C2; Sat, 20 Feb 2021 09:01:01 +0000 (UTC) Subject: Re: [PATCH RFC] mm/madvise: introduce MADV_POPULATE to prefault/prealloc memory To: Mike Kravetz , Peter Xu Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Arnd Bergmann , Michal Hocko , Oscar Salvador , Matthew Wilcox , Andrea Arcangeli , Minchan Kim , Jann Horn , Jason Gunthorpe , Dave Hansen , Hugh Dickins , Rik van Riel , "Michael S . Tsirkin" , "Kirill A . Shutemov" , Vlastimil Babka , Richard Henderson , Ivan Kokshaysky , Matt Turner , Thomas Bogendoerfer , "James E.J. Bottomley" , Helge Deller , Chris Zankel , Max Filippov , linux-alpha@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linux-xtensa@linux-xtensa.org, linux-arch@vger.kernel.org References: <20210217154844.12392-1-david@redhat.com> <20210218225904.GB6669@xz-x1> <20210219163157.GF6669@xz-x1> <41444eb8-8bb8-8d5b-4cec-be7fa7530d0e@redhat.com> <4d8e6f55-66a6-d701-6a94-79f5e2b23e46@redhat.com> <15da147c-e440-ee87-c505-a4684a5b29dc@oracle.com> From: David Hildenbrand Organization: Red Hat GmbH Message-ID: <2073702b-9e09-2033-2915-628c7b7ccb3d@redhat.com> Date: Sat, 20 Feb 2021 10:01:00 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.0 MIME-Version: 1.0 In-Reply-To: <15da147c-e440-ee87-c505-a4684a5b29dc@oracle.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org > Sorry, for jumping in late ... hugetlb keyword just hit my mail filters :) > Sorry for not realizing to cc you before I sent out the man page update :) > Yes, it is true that hugetlb reservations are not numa aware. So, even if > pages are reserved at mmap time one could still SIGBUS if a fault is > restricted to a node with insufficient pages. > > I looked into this some years ago, and there really is not a good way to > make hugetlb reservations numa aware. preallocation, or on demand > populating as proposed here is a way around the issue. Thanks for confirming, this makes a lot of sense to me now. -- Thanks, David / dhildenb