From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail02.groups.io (mail02.groups.io [66.175.222.108]) by spool.mail.gandi.net (Postfix) with ESMTPS id 8D8A0941D8F for ; Tue, 13 Feb 2024 17:31:18 +0000 (UTC) DKIM-Signature: a=rsa-sha256; bh=9PhBUL+E0Yk/XxSabAXk97S+XEGfACFcIIOSEbdDHSU=; c=relaxed/simple; d=groups.io; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From:In-Reply-To:Precedence:List-Subscribe:List-Help:Sender:List-Id:Mailing-List:Delivered-To:Reply-To:List-Unsubscribe-Post:List-Unsubscribe:Content-Language:Content-Type:Content-Transfer-Encoding; s=20140610; t=1707845477; v=1; b=C0WmpwNVbl+cvxi8bSM0zTEGztwfHtTiT0kC250FXa42j0s02HzdRlmGGWcXd9BiQu6yCDS5 9oOjCHB7m8nLetxl3qm/rd0lmIrt/PtRxd0GdWNX+R2thMyvs3S1f7qae1jSCdNPh08kD3HMEdn xr90c4KzyzncyxbNjyAkD0i0= X-Received: by 127.0.0.2 with SMTP id I1EoYY7687511xD3UeKktyia; Tue, 13 Feb 2024 09:31:17 -0800 X-Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by mx.groups.io with SMTP id smtpd.web10.17837.1707845476626556232 for ; Tue, 13 Feb 2024 09:31:16 -0800 X-Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-202-V3vOHET0M1elR1tjhlIhzQ-1; Tue, 13 Feb 2024 12:31:13 -0500 X-MC-Unique: V3vOHET0M1elR1tjhlIhzQ-1 X-Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (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 mimecast-mx02.redhat.com (Postfix) with ESMTPS id D9EAF3813BC2; Tue, 13 Feb 2024 17:31:12 +0000 (UTC) X-Received: from [10.39.192.66] (unknown [10.39.192.66]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 83A362166B31; Tue, 13 Feb 2024 17:31:11 +0000 (UTC) Message-ID: Date: Tue, 13 Feb 2024 18:31:10 +0100 MIME-Version: 1.0 Subject: Re: [edk2-devel] [PATCH 1/1] OvmfPkg/QemuVideoDxe: purge VbeShim To: Pedro Falcato , Gerd Hoffmann Cc: Ard Biesheuvel , devel@edk2.groups.io, Oliver Steffen , Ard Biesheuvel , Jiewen Yao , dun.tan@intel.com References: <20240213085925.687848-1-kraxel@redhat.com> <64005185-3cfd-de56-f086-da301aff13ba@redhat.com> From: "Laszlo Ersek" In-Reply-To: X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.6 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Precedence: Bulk List-Subscribe: List-Help: Sender: devel@edk2.groups.io List-Id: Mailing-List: list devel@edk2.groups.io; contact devel+owner@edk2.groups.io Reply-To: devel@edk2.groups.io,lersek@redhat.com List-Unsubscribe-Post: List-Unsubscribe=One-Click List-Unsubscribe: X-Gm-Message-State: bwjsUlNMyawh6alpoFy7Z2Wxx7686176AA= Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-GND-Status: LEGIT Authentication-Results: spool.mail.gandi.net; dkim=pass header.d=groups.io header.s=20140610 header.b=C0WmpwNV; dmarc=fail reason="SPF not aligned (relaxed), DKIM not aligned (relaxed)" header.from=redhat.com (policy=none); spf=pass (spool.mail.gandi.net: domain of bounce@groups.io designates 66.175.222.108 as permitted sender) smtp.mailfrom=bounce@groups.io On 2/13/24 16:47, Pedro Falcato wrote: > On Tue, Feb 13, 2024 at 3:28 PM Gerd Hoffmann wrote: >> >> Hi, >> >>>>> New theory: This is a NULL pointer dereference corrupting the zero page. >>>> >>>> Tangentially related: Maybe it's time to unmap the NULL page? :) >> >> Suggestion: read mails to the end. Had the same idea + question ;) > > Sorry! My bad. Apparently I don't know how to read ;) > >> >>> That would break many 3rd party GPU and network drivers. >> >> For virtual machine firmware it might be acceptable to just ignore >> that, or at least default to an unmapped zero page and offer an >> qemu fw-cfg override in case someone needs that when pci-assigning >> nic or gpu to a VM. > > IMO this is a really nice suggestion. Could QEMU be modified to inject > the fwcfg option if a VFIO device is present or something? Would that > solve most of the compatibility issues? Are OVMF and QEMU usually > packaged (distro-side) in somewhat of a lockstep? > Trying to integrate this closely with QEMU looks like a recipe for derailment, if past experience is to be listened to... Laszlo -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#115401): https://edk2.groups.io/g/devel/message/115401 Mute This Topic: https://groups.io/mt/104329097/7686176 Group Owner: devel+owner@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [rebecca@openfw.io] -=-=-=-=-=-=-=-=-=-=-=-