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=-6.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 9139DC3A59B for ; Sat, 17 Aug 2019 09:14:27 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 450B22075E for ; Sat, 17 Aug 2019 09:14:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="mvJ529A/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 450B22075E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D2D376B0007; Sat, 17 Aug 2019 05:14:26 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CB6D86B000A; Sat, 17 Aug 2019 05:14:26 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B57A16B000C; Sat, 17 Aug 2019 05:14:26 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0024.hostedemail.com [216.40.44.24]) by kanga.kvack.org (Postfix) with ESMTP id 929756B0007 for ; Sat, 17 Aug 2019 05:14:26 -0400 (EDT) Received: from smtpin19.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id 43D0B8248AD6 for ; Sat, 17 Aug 2019 09:14:26 +0000 (UTC) X-FDA: 75831358932.19.ear16_26ac7de3f7959 X-HE-Tag: ear16_26ac7de3f7959 X-Filterd-Recvd-Size: 4314 Received: from mail-ed1-f66.google.com (mail-ed1-f66.google.com [209.85.208.66]) by imf15.hostedemail.com (Postfix) with ESMTP for ; Sat, 17 Aug 2019 09:14:25 +0000 (UTC) Received: by mail-ed1-f66.google.com with SMTP id g8so7102843edm.6 for ; Sat, 17 Aug 2019 02:14:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Sirr0PNWi30rC1+3FoJFRyHctdtSV+xSzXjml2UEUC4=; b=mvJ529A/blvAFkMU0nkpXUBqz+Yk2QjPFjBP3Sn3pBPDEC6EGRey+JFkd+viVaYzXb 8oudACB0vsLfN2fo63EIDmVE7slQCVBLL1vrUgW9cTrxhNPQ9k5QvhhItUIycUSyCFAj xCk/XxFyo2O82cg/ToR2jzwSBfYlJxvXXKgocycw7Kp6Aixk1aW6HxdNmcz7Un6AZY03 0LXD+CifY8ayqjXyDsQMH9NuyUDEZ/pf7205OnhWtdvTlWuhXUdkkXmz0lH9GbiVcRbG eDYoN+U44rBrE0dyd+NuYJJD8CNWDUr6Tpuncmhzpxly8nw7lNQaBswAve2VZPN3Y9Bf T7Vg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Sirr0PNWi30rC1+3FoJFRyHctdtSV+xSzXjml2UEUC4=; b=BI08+1LQRoGVMpCWhxC/nOG6wozlwddbhQdb5y8VXnXlSgsMk0V8IeoJIGnclTwzpH K1DpccLU78igD8GdIJH/lxkNpB+pNF7eXzADZ+YNn3hlw00fKCQEazvuPTw7NFswXxqE otzM+PtG87ynkXUfUI5yRkrGyhnm8GOkKkvlpp0VCm1Mg3W/7mDXvNmLI7rIawnxgZVK EAIbCb0icc+3b9hmmIkErjy2IFO4Kzo/hvQKlne3OZMVrO0SRCk4mXcxJHxy2YdMAuHt ynXSpz3U8p2ZjU7DjgD4TMlJBb0BHX+DENGrMCOO87nKvlOoXNR7IcanSL8+9OymItke p4rQ== X-Gm-Message-State: APjAAAW4KH5YOKAs6aRCviUEaWlghpKYNt85M8geS5mUaXuv+ctogIJW G/Wu3U2BgVqLTJc/HgSdzeITgG8zc8gXFcvMRW8= X-Google-Smtp-Source: APXvYqx8YnCqgmW+SJMM2KxQi7LlM/1/loQXZvtlig2ikAJSeV0lKhadRN+FfbIn1ocNg/q9kdwGfz8QG+DIlsEjpWs= X-Received: by 2002:a17:906:2310:: with SMTP id l16mr6536483eja.0.1566033264390; Sat, 17 Aug 2019 02:14:24 -0700 (PDT) MIME-Version: 1.0 References: <1566010813-27219-1-git-send-email-huangzhaoyang@gmail.com> <20190817090021.GA10627@rapoport-lnx> In-Reply-To: <20190817090021.GA10627@rapoport-lnx> From: Zhaoyang Huang Date: Sat, 17 Aug 2019 17:14:13 +0800 Message-ID: Subject: Re: [PATCH] arch : arm : add a criteria for pfn_valid To: Mike Rapoport Cc: Andrew Morton , Zhaoyang Huang , Russell King , Rob Herring , Florian Fainelli , Geert Uytterhoeven , Doug Berger , "open list:MEMORY MANAGEMENT" , LKML Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sat, Aug 17, 2019 at 5:00 PM Mike Rapoport wrote: > > On Sat, Aug 17, 2019 at 11:00:13AM +0800, Zhaoyang Huang wrote: > > From: Zhaoyang Huang > > > > pfn_valid can be wrong while the MSB of physical address be trimed as pfn > > larger than the max_pfn. > > How the overflow of __pfn_to_phys() is related to max_pfn? > Where is the guarantee that __pfn_to_phys(max_pfn) won't overflow? eg, the invalid pfn value as 0x1bffc0 will pass pfn_valid if there is a memory block while the max_pfn is 0xbffc0. In ARM64, bellowing condition check will help to > > > Signed-off-by: Zhaoyang Huang > > --- > > arch/arm/mm/init.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c > > index c2daabb..9c4d938 100644 > > --- a/arch/arm/mm/init.c > > +++ b/arch/arm/mm/init.c > > @@ -177,7 +177,8 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max_low, > > #ifdef CONFIG_HAVE_ARCH_PFN_VALID > > int pfn_valid(unsigned long pfn) > > { > > - return memblock_is_map_memory(__pfn_to_phys(pfn)); > > + return (pfn > max_pfn) ? > > + false : memblock_is_map_memory(__pfn_to_phys(pfn)); > > } > > EXPORT_SYMBOL(pfn_valid); > > #endif > > -- > > 1.9.1 > > > > -- > Sincerely yours, > Mike. >