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=-23.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL 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 72C48C47094 for ; Thu, 10 Jun 2021 06:45:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4AD2D613CA for ; Thu, 10 Jun 2021 06:45:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230040AbhFJGrK (ORCPT ); Thu, 10 Jun 2021 02:47:10 -0400 Received: from mail-qv1-f46.google.com ([209.85.219.46]:37597 "EHLO mail-qv1-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229634AbhFJGrJ (ORCPT ); Thu, 10 Jun 2021 02:47:09 -0400 Received: by mail-qv1-f46.google.com with SMTP id x6so9267347qvx.4 for ; Wed, 09 Jun 2021 23:45:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:in-reply-to:message-id:references :mime-version; bh=akymlcTjak2aiLxju3nvGrvixCmoGtWlsFfmG/UDbtE=; b=MkEt15JmyYSAQ+RVuy42Ljti0kzjYxMG1NcV1cwy50nRl6vRoncOkzghyDe4se7H+c GK3oAdp+cr0pMytWAFXnCaZIP4PXXPmxt/GGtorivsAlQ9wr1WPTY9pb3okv4y0hwjWF f0ig6Dbf2GWBXHvC60iY2h+R1mWvaMi7U/s/zfiDez2w0O2cFGJPFrLauq2XgwlaEa1Z JmvhibYkqss7F/ZFx9im9UzrewbbehaLv92KMQFhWZ9noj0+mgW2LhK3ahjypVq7E/v6 Drh9gSNvhsUL9EHI8CUMP13xFZiYfJNRf6yVODI6iBHsjEKBeRao0mE/LGsEJqoPyc9U 9UYg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:in-reply-to:message-id :references:mime-version; bh=akymlcTjak2aiLxju3nvGrvixCmoGtWlsFfmG/UDbtE=; b=hbuNz1sCNC6B2GPraPvODQGn+tO7c15cDW0ZMvR0tk11zJU5svvRbHI4jvx7Oaa1n8 LJMsTFUWRROfoqb2gd1dXndXSGA9KrMI2rdBRRAXeXTJsVtVTdCcSHPZk7GUMbJOOTFq bANli3uUxbAbO6bJAZDjp6lzvvxKp9/23mkDKUdDIFBTMcCMJow9rsqBsl5LYbp26nCP jPaIWPdYn4MPy1pQ0e15W8VrXmx88xO/8rE9VJduQnyYvIUneF1Ocd+tYtfLplOvFOZh 5hTY06wToDAMVgycbfnX/EarxcfmiaYMkFO0TvWjlFpLxlSOn0LE0Kyve9AqDLcIqf8d Ji/Q== X-Gm-Message-State: AOAM532UQhmToqa00LLn1fE7eXAiwwkVYJKLjeLl+7k+1NsGMCc9YC+n 1UNFaLRv9SRZh2GgpaASmwHUHw== X-Google-Smtp-Source: ABdhPJw+h+5g4qsaqPq9hBVqb+DYjhTLlr01z83/WwZH9CfNzJzW4AMFaeYoGQbJMjmA43tYbaijbg== X-Received: by 2002:a05:6214:260b:: with SMTP id gu11mr3840211qvb.12.1623307453261; Wed, 09 Jun 2021 23:44:13 -0700 (PDT) Received: from ripple.attlocal.net (172-10-233-147.lightspeed.sntcca.sbcglobal.net. [172.10.233.147]) by smtp.gmail.com with ESMTPSA id p8sm1598335qkm.119.2021.06.09.23.44.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 09 Jun 2021 23:44:12 -0700 (PDT) Date: Wed, 9 Jun 2021 23:44:10 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@ripple.anvils To: Andrew Morton cc: Hugh Dickins , "Kirill A. Shutemov" , Yang Shi , Wang Yugui , Matthew Wilcox , Alistair Popple , Ralph Campbell , Zi Yan , Peter Xu , Will Deacon , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH 06/11] mm: page_vma_mapped_walk(): crossing page table boundary In-Reply-To: <589b358c-febc-c88e-d4c2-7834b37fa7bf@google.com> Message-ID: <799b3f9c-2a9e-dfef-5d89-26e9f76fd97@google.com> References: <589b358c-febc-c88e-d4c2-7834b37fa7bf@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org page_vma_mapped_walk() cleanup: adjust the test for crossing page table boundary - I believe pvmw->address is always page-aligned, but nothing else here assumed that; and remember to reset pvmw->pte to NULL after unmapping the page table, though I never saw any bug from that. Signed-off-by: Hugh Dickins Cc: --- mm/page_vma_mapped.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index b96fae568bc2..0fe6e558d336 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -247,16 +247,16 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) if (pvmw->address >= end) return not_found(pvmw); /* Did we cross page table boundary? */ - if (pvmw->address % PMD_SIZE == 0) { - pte_unmap(pvmw->pte); + if ((pvmw->address & (PMD_SIZE - PAGE_SIZE)) == 0) { if (pvmw->ptl) { spin_unlock(pvmw->ptl); pvmw->ptl = NULL; } + pte_unmap(pvmw->pte); + pvmw->pte = NULL; goto restart; - } else { - pvmw->pte++; } + pvmw->pte++; } while (pte_none(*pvmw->pte)); if (!pvmw->ptl) { -- 2.26.2