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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 78FE4C388F9 for ; Sun, 8 Nov 2020 14:15:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3F88F208B6 for ; Sun, 8 Nov 2020 14:15:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=bytedance-com.20150623.gappssmtp.com header.i=@bytedance-com.20150623.gappssmtp.com header.b="dtAkgmRZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728942AbgKHOPT (ORCPT ); Sun, 8 Nov 2020 09:15:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35724 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728933AbgKHOPR (ORCPT ); Sun, 8 Nov 2020 09:15:17 -0500 Received: from mail-pl1-x643.google.com (mail-pl1-x643.google.com [IPv6:2607:f8b0:4864:20::643]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A300AC0613D3 for ; Sun, 8 Nov 2020 06:15:16 -0800 (PST) Received: by mail-pl1-x643.google.com with SMTP id b12so3263306plr.4 for ; Sun, 08 Nov 2020 06:15:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=OnGydSB89Ks+7A/rv+/g9HtnO+i1rkH3g7IQtAkMLnc=; b=dtAkgmRZvJyerFmLgvB020I8l7g2zfjdCP5+XPHwtRIVlzmSxGCms9ehfCCLZVR0al K3JEfW3a2cb5lBH7KjGzZyZrkL7hgeK/f2RD4IsS1Kj345ewDSKl0gN8nT7fWfEfkcJI u3b8lh2Q+kTTgqwf898OshwauP1wqeUPYm+BywQDdmDrksbRVO1bTpuqODZQMUA+Tbup U2492FOYkIMh79TDUAZeLqRQT+FdC0R774chbr3yXZ1IsUjGj+FrqjVTaTMu14zfZLdg F7nJH66mGkbImWLK0uFhhdIxQVUgjXdhbDJSAeXpHhZ5XHlHKi8MJEGRs4dxh8HBN5S5 Qoog== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=OnGydSB89Ks+7A/rv+/g9HtnO+i1rkH3g7IQtAkMLnc=; b=SkoQEcwvIs6VAP/jpSQ36KKWIqUS/u3aEP/8iUnx+pSWh2TE3wXEHwNUQCTIJOZMX2 tZ6lHKtaVVTGe6JYPFmnns3dXBrDuKZgFaf+fHfuBaahEwQtpkpm/UJpKnjboia/e3GY jtQIcAzAmiAD0IOT2ZzZGD/kGubvbMXhnSD3OxOgWOobKEe8HQ+KzV4XzYQAstO4cYVL 5gZbb0UkSb4LelYEI5qmShpAapC8azCiPCtQxYi3Ud4cq8Y6p0bMN2BrGNr5tALP5gER tqjqamOBT1+LqRlYZzFysuyWVpOGdc4fnOCtjKYdSU6Sa82x4xEj5gMn7tlftpdlVUHp zF5g== X-Gm-Message-State: AOAM5325lc922v2cTLKbJLBJIWU2pQOZb2i3CwMLJKDKk+/tPXxklozy 0p6B9myIOlK7mHEMSJQhsfXBAQ== X-Google-Smtp-Source: ABdhPJw5tONPh/PhIVeqbhhlTnTuEnWt6avZ/HRA/KkSY5X/hL2YRz93iJrM7qp1GWj08vA2LU067Q== X-Received: by 2002:a17:90a:430b:: with SMTP id q11mr8471967pjg.129.1604844916262; Sun, 08 Nov 2020 06:15:16 -0800 (PST) Received: from localhost.localdomain ([103.136.220.94]) by smtp.gmail.com with ESMTPSA id z11sm8754047pfk.52.2020.11.08.06.15.06 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Sun, 08 Nov 2020 06:15:15 -0800 (PST) From: Muchun Song To: corbet@lwn.net, mike.kravetz@oracle.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, dave.hansen@linux.intel.com, luto@kernel.org, peterz@infradead.org, viro@zeniv.linux.org.uk, akpm@linux-foundation.org, paulmck@kernel.org, mchehab+huawei@kernel.org, pawan.kumar.gupta@linux.intel.com, rdunlap@infradead.org, oneukum@suse.com, anshuman.khandual@arm.com, jroedel@suse.de, almasrymina@google.com, rientjes@google.com, willy@infradead.org, osalvador@suse.de, mhocko@suse.com Cc: duanxiongchun@bytedance.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Muchun Song Subject: [PATCH v3 21/21] mm/hugetlb: Add BUILD_BUG_ON to catch invalid usage of tail struct page Date: Sun, 8 Nov 2020 22:11:13 +0800 Message-Id: <20201108141113.65450-22-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20201108141113.65450-1-songmuchun@bytedance.com> References: <20201108141113.65450-1-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org There are only `RESERVE_VMEMMAP_SIZE / sizeof(struct page)` struct pages can be used when CONFIG_HUGETLB_PAGE_FREE_VMEMMAP, so add a BUILD_BUG_ON to catch this invalid usage of tail struct page. Signed-off-by: Muchun Song --- mm/hugetlb.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 1dd1a9cec008..66b96705597a 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3946,6 +3946,8 @@ static int __init hugetlb_init(void) #ifdef CONFIG_HUGETLB_PAGE_FREE_VMEMMAP BUILD_BUG_ON_NOT_POWER_OF_2(sizeof(struct page)); + BUILD_BUG_ON(NR_USED_SUBPAGE >= + RESERVE_VMEMMAP_SIZE / sizeof(struct page)); #endif if (!hugepages_supported()) { -- 2.11.0