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: <1498206688.24807.5.camel@redhat.com>
Date:   Fri, 23 Jun 2017 10:31:28 +0200
From:   Gerd Hoffmann <kraxel@...hat.com>
To:     Zhi Wang <zhi.a.wang@...el.com>,
        Alex Williamson <alex.williamson@...hat.com>
Cc:     "Wang, Zhenyu Z" <zhenyu.z.wang@...el.com>,
        "intel-gfx@...ts.freedesktop.org" <intel-gfx@...ts.freedesktop.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "Chen, Xiaoguang" <xiaoguang.chen@...el.com>,
        "Zhang, Tina" <tina.zhang@...el.com>,
        Kirti Wankhede <kwankhede@...dia.com>,
        "Lv, Zhiyuan" <zhiyuan.lv@...el.com>,
        "intel-gvt-dev@...ts.freedesktop.org" 
        <intel-gvt-dev@...ts.freedesktop.org>
Subject: Re: [Intel-gfx] [PATCH v9 5/7] vfio: Define vfio based dma-buf
 operations

On Fri, 2017-06-23 at 15:49 +0800, Zhi Wang wrote:
> Hi:
>      Thanks for the discussions! If the userspace application has 
> already maintained a LRU list, it looks like we don't need
> generation 
> anymore,

generation isn't required, things are working just fine without that. 
It is just a small optimization, userspace can skip the LRU lookup
altogether if the generation didn't change.

But of couse that only pays off if the kernel doesn't has to put much
effort into maintaining the generation id.  Something simple like
increasing it each time the guest writes a register which affects
plane_info.

If you think it doesn't make sense from the driver point of view we can
drop the generation.

cheers,
  Gerd

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ