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=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 33BE4C64E7A for ; Tue, 24 Nov 2020 09:59:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 921BF20708 for ; Tue, 24 Nov 2020 09:59:52 +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="fU4syUhx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731814AbgKXJ7f (ORCPT ); Tue, 24 Nov 2020 04:59:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57564 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731779AbgKXJ7a (ORCPT ); Tue, 24 Nov 2020 04:59:30 -0500 Received: from mail-pf1-x442.google.com (mail-pf1-x442.google.com [IPv6:2607:f8b0:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C9E7DC061A4D for ; Tue, 24 Nov 2020 01:59:30 -0800 (PST) Received: by mail-pf1-x442.google.com with SMTP id v12so17968974pfm.13 for ; Tue, 24 Nov 2020 01:59:30 -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=Bynt/1YGSIdeJG2cOcgImXpzmEpwnUEaY6/7f6Ae/g4=; b=fU4syUhxdPJXkfQh34bMos1Y3zr1DCPrRNdijHklOltKrH8VvpAXtOADs20QwQcEjW A2lK/GIaljVc1gKpKY+vWKXPR9OX02jV7LL2OxqKTKdW4TMY9bWP+fnxOuc6z68yESqq gPQsJIyUY3JrkeRY5zHkeN2Y8rM6TmLsRERR3l+Scp4P6MJ+uxijHnXpyVuclcExnT3i gzDQQIfKE2CNH1P5PIdE0F04T9wEPhqMpEHIzsrjT1bfyLdmVV1Yc+Rcj7e9TKtK/A6B 43CvqdjuVYMGBrGRpCljlvKSDsJaaJr0BCU5Ev8i5DzEfhLX4j3RvZAfincG31o5Ls53 GL8Q== 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=Bynt/1YGSIdeJG2cOcgImXpzmEpwnUEaY6/7f6Ae/g4=; b=K9gWQu1BzVjDC1h3ICVDPwEcHmeJVgrCd+zPfqEuoxCb6GZ0aEAb8sWlOaPPCfohij dZJGiKQBOlJ/WdI1eAM2YIHWErjkwDDNShELIy/XhrEBrNBhHAZyAukbNdR8tRkb5A6X s1drygKcSOJlewlGqeGdjSbsd5eF6DuqjMOIKdo4ddlxp9US6P6YlHkgN9nDdqfG/W7E 1clh4UWnzsWR2jEFTe9pyxqSO7etOk7YDf6wkI6BZhjM+6vsNGgiybg02By7/8+BAqF3 217g/qJ03r8+4tusYXf0Ze6Gx2grw1joZbGE0Y+zHZv9+vNfPFZtb/Qc3rbsqOVkiXik wX3g== X-Gm-Message-State: AOAM5307Ts94poDQ9fozJ7pC2yWR5t4+Usp5t8Txeb79Z305BCmG1x+o PjCzttcCOA3RTsF2w6jHNARuPA== X-Google-Smtp-Source: ABdhPJy1pVteQcfd7t6pUTOEaOSYXhdcK1qTpL/2aKqFlzz5VS2SYxybBYu983LImuXmPOsDkOMJAQ== X-Received: by 2002:a63:f857:: with SMTP id v23mr3071328pgj.174.1606211970431; Tue, 24 Nov 2020 01:59:30 -0800 (PST) Received: from localhost.localdomain ([103.136.220.120]) by smtp.gmail.com with ESMTPSA id t20sm2424562pjg.25.2020.11.24.01.59.19 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 24 Nov 2020 01:59:29 -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 v6 16/16] mm/hugetlb: Add BUILD_BUG_ON to catch invalid usage of tail struct page Date: Tue, 24 Nov 2020 17:52:59 +0800 Message-Id: <20201124095259.58755-17-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20201124095259.58755-1-songmuchun@bytedance.com> References: <20201124095259.58755-1-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 b2222f8d1245..d2c013582110 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -338,6 +338,9 @@ void __init hugetlb_vmemmap_init(struct hstate *h) unsigned int order = huge_page_order(h); unsigned int vmemmap_pages; + BUILD_BUG_ON(NR_USED_SUBPAGE >= + RESERVE_VMEMMAP_SIZE / sizeof(struct page)); + if (!is_power_of_2(sizeof(struct page)) || !hugetlb_free_vmemmap_enabled) { pr_info("disable freeing vmemmap pages for %s\n", h->name); -- 2.11.0