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=-6.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,USER_AGENT_GIT 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 8C2EEC433DB for ; Sat, 9 Jan 2021 07:35:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5333F239D4 for ; Sat, 9 Jan 2021 07:35:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726427AbhAIHfW (ORCPT ); Sat, 9 Jan 2021 02:35:22 -0500 Received: from mailgw01.mediatek.com ([210.61.82.183]:41129 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725892AbhAIHfW (ORCPT ); Sat, 9 Jan 2021 02:35:22 -0500 X-UUID: 8283239f5cd546f49b0c3acee954c681-20210109 X-UUID: 8283239f5cd546f49b0c3acee954c681-20210109 Received: from mtkcas10.mediatek.inc [(172.21.101.39)] by mailgw01.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.14 Build 0819 with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1161108416; Sat, 09 Jan 2021 15:34:36 +0800 Received: from MTKCAS06.mediatek.inc (172.21.101.30) by mtkmbs08n2.mediatek.inc (172.21.101.56) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Sat, 9 Jan 2021 15:34:28 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by MTKCAS06.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Sat, 9 Jan 2021 15:34:23 +0800 From: Lecopzer Chen To: CC: , , , , , , , , , , , , , , Subject: Re: [PATCH 0/3] arm64: kasan: support CONFIG_KASAN_VMALLOC Date: Sat, 9 Jan 2021 15:34:23 +0800 Message-ID: <20210109073423.7304-1-lecopzer.chen@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain X-TM-SNTS-SMTP: 7E68C651933D07E578D2C654DCA4A58D67A68FF833FFF0EAAD1CDFA66580C7002000:8 X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Andrey, > > On Sun, Jan 3, 2021 at 6:12 PM Lecopzer Chen wrote: > > > > Linux supports KAsan for VMALLOC since commit 3c5c3cfb9ef4da9 > > ("kasan: support backing vmalloc space with real shadow memory") > > > > Acroding to how x86 ported it [1], they early allocated p4d and pgd, > > but in arm64 I just simulate how KAsan supports MODULES_VADDR in arm64 > > by not to populate the vmalloc area except for kimg address. > > > > Test environment: > > 4G and 8G Qemu virt, > > 39-bit VA + 4k PAGE_SIZE with 3-level page table, > > test by lib/test_kasan.ko and lib/test_kasan_module.ko > > > > It also works in Kaslr with CONFIG_RANDOMIZE_MODULE_REGION_FULL, > > but not test for HW_TAG(I have no proper device), thus keep > > HW_TAG and KASAN_VMALLOC mutual exclusion until confirming > > the functionality. > > Re this: it makes sense to introduce vmalloc support one step a time > and add SW_TAGS support before taking on HW_TAGS. SW_TAGS doesn't > require any special hardware. Working on SW_TAGS first will also allow > dealing with potential conflicts between vmalloc and tags without > having MTE in the picture as well. Just FYI, no need to include that > in this change. Thanks for the information and suggestion, so this serise I'll keep only for KASAN_GENERIC support :) BRs, Lecopzer