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=-15.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1,USER_IN_DEF_DKIM_WL 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 241FAC07E94 for ; Fri, 4 Jun 2021 15:47:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F2E8F61406 for ; Fri, 4 Jun 2021 15:47:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230108AbhFDPtB (ORCPT ); Fri, 4 Jun 2021 11:49:01 -0400 Received: from linux.microsoft.com ([13.77.154.182]:34238 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229809AbhFDPtB (ORCPT ); Fri, 4 Jun 2021 11:49:01 -0400 Received: from [192.168.86.35] (c-73-38-52-84.hsd1.vt.comcast.net [73.38.52.84]) by linux.microsoft.com (Postfix) with ESMTPSA id AE8E520B7178; Fri, 4 Jun 2021 08:47:13 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com AE8E520B7178 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1622821635; bh=Ta7AVDVq80wxtJAhEMWvq0u4Gd9WlURarydMVI8XT1k=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=EvwSr33U36IyVGLo2CVg17brY69lpZrFsmUl6MgJ+yGjNKKMWS2uLcxj9J0FeLCtA JP4K36MdJ9ZcHXSVXw2eK5uSuCwqdCJ6lYnPC66W1FRf8UqbxqEbEG1vfI7nxVmDCf gNIn7BXiph6Hz0wJB+Qs0C71qlqG09i+yYUtgMP0= Subject: Re: [bug report] Commit ccf953d8f3d6 ("fb_defio: Remove custom address_space_operations") breaks Hyper-V FB driver To: Wei Liu , Vitaly Kuznetsov Cc: Matthew Wilcox , dri-devel@lists.freedesktop.org, linux-hyperv@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, Michael Kelley , Dexuan Cui References: <87v96tzujm.fsf@vitty.brq.redhat.com> <20210604130014.tkeozyn4wxdsr6o2@liuwe-devbox-debian-v2> From: Vineeth Pillai Message-ID: Date: Fri, 4 Jun 2021 11:47:13 -0400 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210604130014.tkeozyn4wxdsr6o2@liuwe-devbox-debian-v2> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org On 6/4/2021 9:00 AM, Wei Liu wrote: > On Fri, Jun 04, 2021 at 02:25:01PM +0200, Vitaly Kuznetsov wrote: >> Hi, >> >> Commit ccf953d8f3d6 ("fb_defio: Remove custom address_space_operations") >> seems to be breaking Hyper-V framebuffer >> (drivers/video/fbdev/hyperv_fb.c) driver for me: Hyper-V guest boots >> well and plymouth even works but when I try starting Gnome, virtual >> screen just goes black. Reverting the above mentioned commit on top of >> 5.13-rc4 saves the day. The behavior is 100% reproducible. I'm using >> Gen2 guest runing on Hyper-V 2019. It was also reported that Gen1 guests >> are equally broken. >> >> Is this something known? >> > I've heard a similar report from Vineeth but we didn't get to the bottom > of this. I have just tried reverting the commit mentioned above and it solves the GUI freeze I was also seeing. Previously, login screen was just freezing, but VM was accessible through ssh. With the above commit reverted, I can login to Gnome. Looks like I am also experiencing the same bug mentioned here. Thanks, Vineeth