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=-12.7 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,URIBL_BLOCKED,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 4B668C388F7 for ; Fri, 13 Nov 2020 11:08:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D1E80207DE for ; Fri, 13 Nov 2020 11:08:54 +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="acPhX2RT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726751AbgKMLIT (ORCPT ); Fri, 13 Nov 2020 06:08:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54058 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726438AbgKMLGB (ORCPT ); Fri, 13 Nov 2020 06:06:01 -0500 Received: from mail-pg1-x544.google.com (mail-pg1-x544.google.com [IPv6:2607:f8b0:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1B80DC094250 for ; Fri, 13 Nov 2020 03:04:46 -0800 (PST) Received: by mail-pg1-x544.google.com with SMTP id h6so6821324pgk.4 for ; Fri, 13 Nov 2020 03:04:46 -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=9fcYda0AgPV/WnXKlnMuFEs34xJLysA9FVwvOk3sXIs=; b=acPhX2RT/KAG0d/biBqn+RStXr042kHnAgVWmRzsh8fygXJWhjB4LGnM3ArK78IYHy 05M1F8hixARWaE1jYAwk1yTcqe4rYbkfaAHkyKyIi4+8+9KuXuglgShz7W6hkk/X9HE1 N2n5uQS2/wDQuZFTzGZ2NDZiK2mDbfUba6OJJMr87S9/fgyc80MoT7cLUTQ0vFQyAdgF du7NuXu0ZzcYLYPUkUpImZuusIrbVD8hT0F5R4Tcs5ycO3EjK1rKcs04htAn854HEBTd hZoDX34VvtIBK69tAyNUPPlre/Wvo5RGsq3oAxvzDW7F326FTW5eb4uxR5bfOdkM8Pbw Eazg== 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=9fcYda0AgPV/WnXKlnMuFEs34xJLysA9FVwvOk3sXIs=; b=Ek6pNkLWg4SWl4OdSBJN/EhsXs6o/jW1UGl0Ipoo3XFvqVNcJvMnbrTms2e/uqBe3+ 4LNKvrmk352+TX6XrNk7tBcWe4MS0pQR7ZgfLXN3kCe9J05b1qnqA17B7w/8W0oETjHR 5k9COXF4I4fYdobOxJMGl0W81+AVGV0WoA4PvXXkTxlDO/ndUetoiH4M5lDUan9zZS+1 QmJ1qSFKKwV+QizV4Gr5Q/HnmZcMRd3aWdloNHp1Xf86NUvjM0To+VYWdHwSB0Y46L6R WfzHqBFMI3PyxO+fpZEvx90ra+bROeJREHr2vgk759JhpvNqLZlKCbRgXXCXGqGCfgw/ 42qA== X-Gm-Message-State: AOAM531GBsjerW5JROeKNxWIxE6QlOQFjRp05s/edM602rUwL4hZVGyt GwxmLXRyfgmBf7kJhJHFYkYd7Q== X-Google-Smtp-Source: ABdhPJy3y4l2jKKhlBarikLuHDHXd6EaPh5lhfhf6nys027+oDsqWvIQDzCElVYorC4v+mz0uMOCFA== X-Received: by 2002:a17:90a:d184:: with SMTP id fu4mr1106379pjb.173.1605265485688; Fri, 13 Nov 2020 03:04:45 -0800 (PST) Received: from localhost.localdomain ([61.120.150.78]) by smtp.gmail.com with ESMTPSA id f1sm8909959pfc.56.2020.11.13.03.04.34 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 13 Nov 2020 03:04:45 -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 v4 20/21] mm/hugetlb: Add BUILD_BUG_ON to catch invalid usage of tail struct page Date: Fri, 13 Nov 2020 18:59:51 +0800 Message-Id: <20201113105952.11638-21-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20201113105952.11638-1-songmuchun@bytedance.com> References: <20201113105952.11638-1-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 5c00826a98b3..f67aec6e3bb1 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -717,6 +717,9 @@ 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