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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 5C07FC3E8AB for ; Sat, 5 Oct 2019 12:29:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E9046222CB for ; Sat, 5 Oct 2019 12:29:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=shipmail.org header.i=@shipmail.org header.b="eXiaWehj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728150AbfJEM3q (ORCPT ); Sat, 5 Oct 2019 08:29:46 -0400 Received: from pio-pvt-msa2.bahnhof.se ([79.136.2.41]:51212 "EHLO pio-pvt-msa2.bahnhof.se" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726198AbfJEM3p (ORCPT ); Sat, 5 Oct 2019 08:29:45 -0400 Received: from localhost (localhost [127.0.0.1]) by pio-pvt-msa2.bahnhof.se (Postfix) with ESMTP id 6D6FD3F9CA; Sat, 5 Oct 2019 14:29:43 +0200 (CEST) Authentication-Results: pio-pvt-msa2.bahnhof.se; dkim=pass (1024-bit key; unprotected) header.d=shipmail.org header.i=@shipmail.org header.b=eXiaWehj; dkim-atps=neutral X-Virus-Scanned: Debian amavisd-new at bahnhof.se Received: from pio-pvt-msa2.bahnhof.se ([127.0.0.1]) by localhost (pio-pvt-msa2.bahnhof.se [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ZvVhr-XueHu5; Sat, 5 Oct 2019 14:29:42 +0200 (CEST) Received: from mail1.shipmail.org (h-205-35.A357.priv.bahnhof.se [155.4.205.35]) (Authenticated sender: mb878879) by pio-pvt-msa2.bahnhof.se (Postfix) with ESMTPA id CBC323F9B6; Sat, 5 Oct 2019 14:29:41 +0200 (CEST) Received: from localhost.localdomain (h-205-35.A357.priv.bahnhof.se [155.4.205.35]) by mail1.shipmail.org (Postfix) with ESMTPSA id 3C13836014C; Sat, 5 Oct 2019 14:29:41 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=shipmail.org; s=mail; t=1570278581; bh=/gR1HwYFIIqFRwJfuDUBbZYDELbnZuayqLuZ9ZZV6b8=; h=To:Cc:From:Subject:Date:From; b=eXiaWehju1eFoQiw6YFkzE3Wmwwf94Hlc6AH0FmGBSkirtIB4zPrIT4711WNqm61c zLQR7fVqctWxaw5m5+KLmGCTlXb+NtTUOluIzaZHcnKC0g7doLKFfAY36yXpHHlhFy GMGQLB6uVLjwXeAi8tG3pcQa8gRrtNHlA6wzs9e0= To: Jerome Glisse Cc: "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "Kirill A. Shutemov" From: =?UTF-8?Q?Thomas_Hellstr=c3=b6m_=28VMware=29?= Subject: hmm pud-entry callback locking? Organization: VMware Inc. Message-ID: <4d25d751-d03a-29c6-950b-cafe8d201784@shipmail.org> Date: Sat, 5 Oct 2019 14:29:40 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Jerome, I was asked by Kirill to try to unify the pagewalk pud_entry and pmd_entry callbacks. The only user of the pagewalk pud-entry is currently hmm. But the pagewalk code call pud_entry only for huge puds with the page-table lock held, whereas the hmm callback appears to assume it gets called unconditionally without the page-table lock held? Could you shed some light into this? Thanks, Thomas