linux-kernel - Re: [Xen-devel] [PATCH RFC 00/39] x86/KVM: Xen HVM guest support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <292773f7-5a4d-ba00-8398-0c8b81766b93@oracle.com>
Date:   Wed, 20 Feb 2019 16:31:53 -0800
From:   Ankur Arora <ankur.a.arora@...cle.com>
To:     Marek Marczykowski-Górecki 
        <marmarek@...isiblethingslab.com>,
        Joao Martins <joao.m.martins@...cle.com>
Cc:     kvm@...r.kernel.org, linux-kernel@...r.kernel.org,
        Juergen Gross <jgross@...e.com>,
        Stefano Stabellini <sstabellini@...nel.org>,
        xen-devel@...ts.xenproject.org,
        Radim Krčmář <rkrcmar@...hat.com>,
        x86@...nel.org, Ingo Molnar <mingo@...hat.com>,
        Borislav Petkov <bp@...en8.de>,
        "H. Peter Anvin" <hpa@...or.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Boris Ostrovsky <boris.ostrovsky@...cle.com>,
        Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [Xen-devel] [PATCH RFC 00/39] x86/KVM: Xen HVM guest support



On 2/20/19 3:39 PM, Marek Marczykowski-Górecki wrote:
> On Wed, Feb 20, 2019 at 08:15:30PM +0000, Joao Martins wrote:
>>   2. PV Driver support (patches 17 - 39)
>>
>>   We start by redirecting hypercalls from the backend to routines
>>   which emulate the behaviour that PV backends expect i.e. grant
>>   table and interdomain events. Next, we add support for late
>>   initialization of xenbus, followed by implementing
>>   frontend/backend communication mechanisms (i.e. grant tables and
>>   interdomain event channels). Finally, introduce xen-shim.ko,
>>   which will setup a limited Xen environment. This uses the added
>>   functionality of Xen specific shared memory (grant tables) and
>>   notifications (event channels).
> 
> Does it mean backends could be run in another guest, similarly as on
> real Xen? AFAIK virtio doesn't allow that as virtio backends need
I'm afraid not. For now grant operations (map/unmap) can only be done
by backends to the local KVM instance.

Ankur

> arbitrary write access to guest memory. But grant tables provide enough
> abstraction to do that safely.

>