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 9F5A3C64E8A for ; Mon, 30 Nov 2020 15:22:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 512D620731 for ; Mon, 30 Nov 2020 15:22:48 +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="K3OBTqgX" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728175AbgK3PWl (ORCPT ); Mon, 30 Nov 2020 10:22:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55660 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728165AbgK3PWk (ORCPT ); Mon, 30 Nov 2020 10:22:40 -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 35584C061A48 for ; Mon, 30 Nov 2020 07:21:54 -0800 (PST) Received: by mail-pl1-x643.google.com with SMTP id b23so6644629pls.11 for ; Mon, 30 Nov 2020 07:21:54 -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=fuUKX8d4nSr1QpzefkNAk3vJpwlYcNoKqBePERxkILM=; b=K3OBTqgXSNp5EAH2ATyadig7W4nsC8UODJccBFE53y6L9s/8TLLOcoz+75HFYiNLab 3M/YhR3GwxtJAVVwcar9pVLNNPkWXTz4CN3/fYBm6Z7IAlpc8SSj3mPd+rnH51McUlVd +pxfL7D1MX0zOkGAMCDEVG5dLv2UZM29t+Ba60eazD2nl6LUg4gToJZATV3576mryTaG C+JZppYloYDZw9GnaItvp79nNrEai4JVjsrBvDdoKIGZA+7DNpPwrigco0kci6dPmbG+ bUGZNgPF9tk6CCUWwbl327grbi0FpNJ4Y4BOM7Me4RBcaBcapG2ahQtc5nORyDgybimY KGjQ== 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=fuUKX8d4nSr1QpzefkNAk3vJpwlYcNoKqBePERxkILM=; b=XvTHnHtGhkli8jHybBQMVrKXmJfqGh88rBFEud/3Qi7YK+p933yBM8vfxmAbKJRrHG ixRlDj9trz/ubWfxPETTuBVyze9xCQk6eq+ixd2tZhITzos0bYgZGcLY7gjQGbrzRsms SMN5t1q3lgCXshG/evCQrHEEafjW0N2nuxf9/3pPjXr4rF3lnKNWS7USIfO48wsJvx7R XW3QuKLCeMaEfzTJXFG95B22rPnoujtQMXU1GAHcsI/IWjG7XMF3gK/J26vb9SrmVtal wRvP9ENWcYqwr/WQpzRfua+wZxJbr4qpJXWv9iBOR+54CbNuheI23e7nwvWVS9hJKvo3 6KOg== X-Gm-Message-State: AOAM532K2cZyWVEyhzc29zJb1WqeatITF2wb9u7ccPjaf4khnjxpg+bk ek5v2/k7Ay43t/bYwX/CYE1p/Q== X-Google-Smtp-Source: ABdhPJz6JFlCGHeRqTkVb9tcu3nTa7vPf8NBGUJescRklNe13RCi1870SqkANDzcdyEXLfM5aG8X4w== X-Received: by 2002:a17:902:c154:b029:d6:efa5:4ce7 with SMTP id 20-20020a170902c154b02900d6efa54ce7mr19258396plj.73.1606749713784; Mon, 30 Nov 2020 07:21:53 -0800 (PST) Received: from localhost.bytedance.net ([103.136.221.68]) by smtp.gmail.com with ESMTPSA id q12sm16201660pgv.91.2020.11.30.07.21.44 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 30 Nov 2020 07:21:53 -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 v7 15/15] mm/hugetlb: Add BUILD_BUG_ON to catch invalid usage of tail struct page Date: Mon, 30 Nov 2020 23:18:38 +0800 Message-Id: <20201130151838.11208-16-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20201130151838.11208-1-songmuchun@bytedance.com> References: <20201130151838.11208-1-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 ebc710d148e4..3328de88819e 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -340,6 +340,9 @@ void __init hugetlb_vmemmap_init(struct hstate *h) unsigned int nr_pages = pages_per_huge_page(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