Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Tue, 9 Oct 2018 19:50:57 +0200
From:   Cornelia Huck <cohuck@redhat.com>
To:     Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc:     Christian Borntraeger <borntraeger@de.ibm.com>,
        Filippo Sironi <sironi@amazon.de>,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        xen-devel <xen-devel@lists.xenproject.org>,
        vasu.srinivasan@oracle.com,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: [PATCH] KVM: Start populating /sys/hypervisor with KVM entries
Message-ID: <20181009195057.2dc8fd7b.cohuck@redhat.com>
In-Reply-To: <61740f41-c7e3-edaf-68ac-2e4c4a99523b@oracle.com>
References: <1539078879-4372-1-git-send-email-sironi@amazon.de>
        <c81b65ba-c562-1869-483b-aee5229501e0@de.ibm.com>
        <61740f41-c7e3-edaf-68ac-2e4c4a99523b@oracle.com>
Organization: Red Hat GmbH
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Tue, 9 Oct 2018 12:21:46 -0400
Boris Ostrovsky <boris.ostrovsky@oracle.com> wrote:

> On 10/9/18 6:41 AM, Christian Borntraeger wrote:
> > 
> > 
> > On 10/09/2018 11:54 AM, Filippo Sironi wrote:  
> >> Start populating /sys/hypervisor with KVM entries when we're running on
> >> KVM. This is to replicate functionality that's available when we're
> >> running on Xen.
> >>
> >> Let's start with /sys/hypervisor/uuid, which users prefer over
> >> /sys/devices/virtual/dmi/id/product_uuid as a way to recognize a virtual
> >> machine, since it's also available when running on Xen HVM and on Xen PV
> >> and, on top of that doesn't require root privileges by default.  
> > 
> > Can you make this an arch hook? On s390 it is possible to get the uuid with
> > the stsi instruction. 
> > See
> > https://git.kernel.org/pub/scm/virt/kvm/kvm.git/tree/arch/s390/kernel/sysinfo.c#n248
> > 
> > 
> > We do use uuid_t, but we can certainly return a char*.  
> 
> 
> I would suggest having a top-level sys-hypervisor.c that will create
> common files that all hypervisors should have (uuid, type, version, etc)
> and then have hypervisor- and/or arch-specific hooks.

I think we really need *both* hypervisor- and arch-specific hooks.