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=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,UNPARSEABLE_RELAY,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 A3BE3C4320E for ; Wed, 28 Jul 2021 11:10:10 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9101F60F45 for ; Wed, 28 Jul 2021 11:10:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 9101F60F45 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4GZWCh0q97z30Hp for ; Wed, 28 Jul 2021 21:10:08 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.alibaba.com (client-ip=115.124.30.133; helo=out30-133.freemail.mail.aliyun.com; envelope-from=xianting.tian@linux.alibaba.com; receiver=) X-Greylist: delayed 304 seconds by postgrey-1.36 at boromir; Wed, 28 Jul 2021 19:16:00 AEST Received: from out30-133.freemail.mail.aliyun.com (out30-133.freemail.mail.aliyun.com [115.124.30.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4GZSh05CFjz306d for ; Wed, 28 Jul 2021 19:15:59 +1000 (AEST) X-Alimail-AntiSpam: AC=PASS; BC=-1|-1; BR=01201311R401e4; CH=green; DM=||false|; DS=||; FP=0|-1|-1|-1|0|-1|-1|-1; HT=e01e04420; MF=xianting.tian@linux.alibaba.com; NM=1; PH=DS; RN=7; SR=0; TI=SMTPD_---0UhEfyol_1627463435; Received: from B-LB6YLVDL-0141.local(mailfrom:xianting.tian@linux.alibaba.com fp:SMTPD_---0UhEfyol_1627463435) by smtp.aliyun-inc.com(127.0.0.1); Wed, 28 Jul 2021 17:10:36 +0800 Subject: Re: [PATCH] virtio-console: avoid DMA from vmalloc area To: Arnd Bergmann References: <20210727131217.15092-1-xianting.tian@linux.alibaba.com> <0d03a42b-b46c-408f-17a4-b6c094c0c29e@linux.alibaba.com> From: Xianting Tian Message-ID: Date: Wed, 28 Jul 2021 17:10:35 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.12.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-Mailman-Approved-At: Wed, 28 Jul 2021 21:09:48 +1000 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Amit Shah , gregkh , Linux Kernel Mailing List , "open list:DRM DRIVER FOR QEMU'S CIRRUS DEVICE" , linuxppc-dev , Omar Sandoval Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" 在 2021/7/28 下午5:01, Arnd Bergmann 写道: > On Wed, Jul 28, 2021 at 10:28 AM Xianting Tian > wrote: >> 在 2021/7/28 下午3:25, Arnd Bergmann 写道: >> >> I checked several hvc backends, like drivers/tty/hvc/hvc_riscv_sbi.c, >> drivers/tty/hvc/hvc_iucv.c, drivers/tty/hvc/hvc_rtas.c, they don't use dma. >> >> I not finished all hvc backends check yet. But I think even if all hvc >> backends don't use dma currently, it is still possible that the hvc >> backend using dma will be added in the furture. >> >> So I agree with you it should better be fixed in the hvc framework, >> solve the issue in the first place. > Ok, sounds good to me, no need to check more backends then. > I see the hvc-console driver is listed as 'Odd Fixes' in the maintainer > list, with nobody assigned other than the ppc kernel list (added to Cc). > > Once you come up with a fix in hvc_console.c, please send that to the > tty maintainers, the ppc list and me, and I'll review it. OK, thanks, I will submit the patch ASAP :) > > Arnd