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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 41ADCC2BB1D for ; Fri, 17 Apr 2020 07:10:19 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 0E035206D5 for ; Fri, 17 Apr 2020 07:10:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0E035206D5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=vivo.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 9679D8E0003; Fri, 17 Apr 2020 03:10:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9178B8E0001; Fri, 17 Apr 2020 03:10:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 82D298E0003; Fri, 17 Apr 2020 03:10:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0059.hostedemail.com [216.40.44.59]) by kanga.kvack.org (Postfix) with ESMTP id 66C178E0001 for ; Fri, 17 Apr 2020 03:10:18 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 2950952BA for ; Fri, 17 Apr 2020 07:10:18 +0000 (UTC) X-FDA: 76716473316.16.pump69_3ca8e9843b24f X-HE-Tag: pump69_3ca8e9843b24f X-Filterd-Recvd-Size: 2298 Received: from m176115.mail.qiye.163.com (m176115.mail.qiye.163.com [59.111.176.115]) by imf46.hostedemail.com (Postfix) with SMTP for ; Fri, 17 Apr 2020 07:10:13 +0000 (UTC) Received: from ubuntu.localdomain (unknown [157.0.31.122]) by m176115.mail.qiye.163.com (Hmail) with ESMTPA id 37C2C665296; Fri, 17 Apr 2020 15:10:06 +0800 (CST) From: Bernard Zhao To: Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: kernel@vivo.com, Bernard Zhao Subject: [PATCH] kmalloc_index optimization(add kmalloc max size check) Date: Fri, 17 Apr 2020 00:09:35 -0700 Message-Id: <1587107376-111722-1-git-send-email-bernard@vivo.com> X-Mailer: git-send-email 2.7.4 X-HM-Spam-Status: e1kfGhgUHx5ZQUtXWQgYFAkeWUFZT1VJS09CQkJCSUhMS01LTllXWShZQU hPN1dZLVlBSVdZCQ4XHghZQVk1NCk2OjckKS43PlkG X-HM-Sender-Digest: e1kMHhlZQR0aFwgeV1kSHx4VD1lBWUc6Myo6EQw6ATg4LA4jAxg#CQJD LTcKCz5VSlVKTkNMSktMT0tNT09CVTMWGhIXVRkeCRUaCR87DRINFFUYFBZFWVdZEgtZQVlKTkxV S1VISlVKSUlZV1kIAVlBSUtOQzcG X-HM-Tid: 0a7186f922229373kuws37c2c665296 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000035, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: kmalloc size should never exceed KMALLOC_MAX_SIZE. kmalloc_index realise if size is exceed KMALLOC_MAX_SIZE, e.g 64M, kmalloc_index just return index 26, but never check with OS`s max kmalloc config KMALLOC_MAX_SIZE. This index`s kmalloc caches maybe not create in function create_kmalloc_caches. We can throw an warninginfo in kmalloc at the beginning, instead of being guaranteed by the buddy alloc behind. Signed-off-by: Bernard Zhao --- include/linux/slab.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/include/linux/slab.h b/include/linux/slab.h index 6d45488..59b60d2 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -351,6 +351,10 @@ static __always_inline unsigned int kmalloc_index(size_t size) if (!size) return 0; + /* size should never exceed KMALLOC_MAX_SIZE. */ + if (size > KMALLOC_MAX_SIZE) + WARN(1, "size exceed max kmalloc size!\n"); + if (size <= KMALLOC_MIN_SIZE) return KMALLOC_SHIFT_LOW; -- 2.7.4