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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 7689AC5519F for ; Fri, 20 Nov 2020 06:49:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 223062222F for ; Fri, 20 Nov 2020 06:49:34 +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="IF1543fD" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727158AbgKTGt2 (ORCPT ); Fri, 20 Nov 2020 01:49:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45484 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725890AbgKTGt0 (ORCPT ); Fri, 20 Nov 2020 01:49:26 -0500 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 61BA3C0613CF for ; Thu, 19 Nov 2020 22:49:26 -0800 (PST) Received: by mail-pf1-x443.google.com with SMTP id q10so6954449pfn.0 for ; Thu, 19 Nov 2020 22:49:26 -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=ZS5213ZHM0b8+f9VjLOiz+1LLqtvqurjNhuD3Z1QgXw=; b=IF1543fDtb+kWKsmeCbYQJE2RKvL98vTCrDCvCNTBaznuoXtdRoONmgowwM077EA1r D1ImG20rzchmyhXqIqqQl53pDl81FzaCOANREsMX20Bi7my3JSv37VpMcPo1QyGhIC/W kjfxyOme9/t0QUXrphAihullLYJaXkDZySzXMhDSBQvRjmeANFmzXuAMUQd4VO5Eg0cX zqAICNAblp8DQIt5wYJuW3S84M82AYFj9qGqTx0bj8pyiBqhsIlfrFd+0NqTblPnHo68 dOWR+79BIzlGrP7e0lvS7TCmkXC4ENFNlq3FoNoiYne32Hm7nCVaWDfJw2hnCO290CeN VWHw== 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=ZS5213ZHM0b8+f9VjLOiz+1LLqtvqurjNhuD3Z1QgXw=; b=hJPkmVyFML/VvG7wmcZRUWCWFOHB0OdI2zW+FZvIUlz6AnDmjTNG7ptXC2bzW40PUV 5zQ7plMxmSz5UYygLvxpvnIp5N9+PRCTPOM81K2DfyNV3DY6YK5VlO3lDXKCcep6KD6E LRMLfFUhP2d7TmaJ/jGI2N/5WQQeNIMfiqoQi5OSCHiFZ5yi4ZzxXAmsIo8jW9DJlBby +DMkTmwN672rragDDct/Pa6USLKZC2dBztZOAD++9pjJsY9nS7ofwPSSjZ521dT6nCgM QbkDjXFfb505/z1lc/MMnSkTjAweMN4nVsBJcJKc9FjeBLuBFQkexeyPtnypDeMKoFRE Rs0A== X-Gm-Message-State: AOAM531qTyzT1nBVnB7l/S1y5czqLWVE2ilDuz7ZSV4huKAiTgdu+X8J ssxtg2Pfq2Jqx5pRII6QjKPU0A== X-Google-Smtp-Source: ABdhPJy/oDjOsfTURQw/n8WyCu22EFp43ZL/0t48CLQVCDRZ8hdfpHxhDoWHshVvTsOfv6IeLOJdAw== X-Received: by 2002:a17:90a:7101:: with SMTP id h1mr3714686pjk.26.1605854965992; Thu, 19 Nov 2020 22:49:25 -0800 (PST) Received: from localhost.localdomain ([103.136.221.72]) by smtp.gmail.com with ESMTPSA id 23sm2220278pfx.210.2020.11.19.22.49.15 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 19 Nov 2020 22:49:25 -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, song.bao.hua@hisilicon.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 v5 20/21] mm/hugetlb: Add BUILD_BUG_ON to catch invalid usage of tail struct page Date: Fri, 20 Nov 2020 14:43:24 +0800 Message-Id: <20201120064325.34492-21-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20201120064325.34492-1-songmuchun@bytedance.com> References: <20201120064325.34492-1-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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_vmemmap.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index bf2b6b3e75af..c3b3fc041903 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -750,6 +750,9 @@ static int __init vmemmap_ptlock_init(void) { int nid; + BUILD_BUG_ON(NR_USED_SUBPAGE >= + RESERVE_VMEMMAP_SIZE / sizeof(struct page)); + if (!hugepages_supported()) return 0; -- 2.11.0