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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 AB0FDC47080 for ; Tue, 1 Jun 2021 09:34:49 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 363AE611CA for ; Tue, 1 Jun 2021 09:34:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 363AE611CA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A40B96B00A8; Tue, 1 Jun 2021 05:34:48 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9F2216B00AA; Tue, 1 Jun 2021 05:34:48 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8913E6B00AB; Tue, 1 Jun 2021 05:34:48 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0115.hostedemail.com [216.40.44.115]) by kanga.kvack.org (Postfix) with ESMTP id 53E7E6B00A8 for ; Tue, 1 Jun 2021 05:34:48 -0400 (EDT) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id E5C70181AC9BF for ; Tue, 1 Jun 2021 09:34:47 +0000 (UTC) X-FDA: 78204645414.01.2CAB326 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by imf08.hostedemail.com (Postfix) with ESMTP id 84EE58019367 for ; Tue, 1 Jun 2021 09:34:35 +0000 (UTC) Received: from dggemv711-chm.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4FvRhV0cnJzWqVH; Tue, 1 Jun 2021 17:30:02 +0800 (CST) Received: from dggpeml500005.china.huawei.com (7.185.36.59) by dggemv711-chm.china.huawei.com (10.1.198.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Tue, 1 Jun 2021 17:34:43 +0800 Received: from [10.174.178.155] (10.174.178.155) by dggpeml500005.china.huawei.com (7.185.36.59) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2176.2; Tue, 1 Jun 2021 17:34:42 +0800 From: Yongqiang Liu Subject: [QUESTION] arm64: mmap to the hugetlbfs with hugepagesize=512M got SIGILL To: , CC: , , , Message-ID: Date: Tue, 1 Jun 2021 17:34:42 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.8.0 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed X-Originating-IP: [10.174.178.155] X-ClientProxiedBy: dggeme704-chm.china.huawei.com (10.1.199.100) To dggpeml500005.china.huawei.com (7.185.36.59) X-CFilter-Loop: Reflected Authentication-Results: imf08.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=huawei.com; spf=pass (imf08.hostedemail.com: domain of liuyongqiang13@huawei.com designates 45.249.212.187 as permitted sender) smtp.mailfrom=liuyongqiang13@huawei.com X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 84EE58019367 X-Stat-Signature: mizptr77fuw9f9nggpuwmx5dwjpo78bc X-HE-Tag: 1622540075-721748 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hi Catalin and Will, when we mmap the addr NULL with MAP_FIXED flag to the hugetlbfs, system=20 will return NULL successfully. My question is: Why mmap to file with the hugepagesize=3D512M=C2=A0 we go= t=20 SIGILL but mmap to the file with hugepagesize=3D2M we got a success ? Her= e=20 is my test steps: =C2=A0=C2=A0=C2=A0 1. echo 10 > /sys/kernel/mm/hugepages/hugepages-2048k= B/nr_hugepages =C2=A0=C2=A0=C2=A0 =C2=A0=C2=A0=C2=A0 echo 10 > /sys/kernel/mm/hugepages= /hugepages-524288kB/nr_hugepages =C2=A0=C2=A0=C2=A0 2. mount none /mnt -t tmpfs =C2=A0=C2=A0=C2=A0 3. mkdir /mnt/huge1 =C2=A0=C2=A0=C2=A0 =C2=A0=C2=A0=C2=A0 mkdir /mnt/huge2 =C2=A0=C2=A0=C2=A0 4. mount none /mnt/huge1 -t hugetlbfs -o pagesize=3D5= 12MB =C2=A0=C2=A0=C2=A0 =C2=A0=C2=A0=C2=A0 mount none /mnt/huge2 -t hugetlbfs= -o pagesize=3D2MB =C2=A0=C2=A0=C2=A0 5. test_case.c =C2=A0=C2=A0=C2=A0 =C2=A0=C2=A0=C2=A0 ... ... =C2=A0=C2=A0=C2=A0 =C2=A0=C2=A0=C2=A0 fd =3D open("/mnt/huge1/file", O_R= DWR | O_CREAT, 0777); =C2=A0=C2=A0=C2=A0 =C2=A0=C2=A0=C2=A0 addr =3D mmap(NULL, hugepagesize, = PROT_READ|PROT_WRITE|PROT_EXEC,=20 MAP_PRIVATE | MAP_FIXED, fd, 0); =C2=A0=C2=A0=C2=A0 =C2=A0=C2=A0=C2=A0 ... ... The result is , mmap to the /mnt/huge1/file will got a success while=20 mmap to the /mnt/huge2/file will got SIGILL. Meanwile, we have found=20 that the kernel return the address NULL success but set the variable fail= ed. Here is the pc when SIGILL occured: =C2=A0=C2=A0=C2=A0 =C2=A0=C2=A0=C2=A0 4009bc:=C2=A0=C2=A0 97ffff7d=C2=A0= =C2=A0=C2=A0 bl=C2=A0 4007b0 pc->4009c0:=C2=A0=C2=A0 aa0003e1=C2=A0=C2=A0=C2=A0 mov x1, x0 Kind regards, Yongqiang Liu