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Date: Tue, 15 Mar 2016 16:23:33 +0200
Message-ID: <CAJ3xEMg5fq3Z2VH_qDjsFmTzhCibAGiXT9oEddEKbwktvSYSQQ@mail.gmail.com>
Subject: Re: [RFC PATCH kernel] Revert "net/mlx4_core: Set UAR page size to
 4KB regardless of system page size"
From: Or Gerlitz <gerlitz.or@gmail.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>, Huy Nguyen <huyn@mellanox.com>,
        Doug Ledford <dledford@redhat.com>,
        Eugenia Emantayev <eugenia@mellanox.com>,
        Hal Rosenstock <hal.rosenstock@gmail.com>,
        Sean Hefty <sean.hefty@intel.com>, Yishai Hadas <yishaih@mellanox.com>,
        Linux Kernel <linux-kernel@vger.kernel.org>,
        "linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>,
        Linux Netdev List <netdev@vger.kernel.org>,
        Paul Mackerras <paulus@samba.org>, Carol L Soto <clsoto@us.ibm.com>,
        Yevgeny Petrilin <yevgenyp@mellanox.com>,
        Daniel Jurgens <danielj@mellanox.com>, Eli Cohen <eli@mellanox.com>
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On Tue, Mar 15, 2016 at 2:18 PM, Christoph Hellwig <hch@infradead.org> wrote:
> On Tue, Mar 15, 2016 at 12:40:06PM +0200, Or Gerlitz wrote:
>> "[..] Regarding backward compatibility in SR-IOV, if hypervisor has
>> this new code, the virtual OS must be updated. [...]"

> Which is broken, we can't break user or guest VM ABIs ever.

Let us check. I was under (the maybe wrong) impression, that before this
patch both PF/VF drivers were not operative on some systems, so on those
systems it's fair to require the VF driver to be patched too.

Or.