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Subject: Re: [PATCH RESEND1 00/12] ALSA: vsnd: Add Xen para-virtualized
 frontend driver
To: Takashi Sakamoto <o-takashi@sakamocchi.jp>,
        Oleksandr Grytsov <al1img@gmail.com>, clemens@ladisch.de
Cc: alsa-devel@alsa-project.org, xen-devel@lists.xen.org,
        linux-kernel@vger.kernel.org, tiwai@suse.com,
        Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
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From: Oleksandr Andrushchenko <andr2000@gmail.com>
Message-ID: <b129960e-b38f-ea94-3e4a-3cd409f7a707@gmail.com>
Date: Fri, 18 Aug 2017 10:23:05 +0300
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On 08/18/2017 10:17 AM, Takashi Sakamoto wrote:
> On Aug 18 2017 14:56, Oleksandr Andrushchenko wrote:
>> Taking into account the fact that the backend we have is a user-space 
>> application
>> running on top of ALSA/PulseAudio we cannot get HW pointers from actual
>> hardware by any means (PulseAudio use-case is the most tough thing in 
>> equation)
>
> You mean that any alsa-lib or libpulse applications run on Dom0 as a
> backend driver for the frontend driver on DomU?
>
No, the sound backend [1] is a user-space application (ALSA/PulseAudio 
client)
which runs as a Xen para-virtual backend in Dom0 and serves all the
frontends running in DomU(s).
Other ALSA/PulseAudio clients in Dom0 are also allowed to run at the
same time.
>
> Regards
>
> Takashi Sakamoto
Thank you,
Oleksandr

[1] https://github.com/xen-troops/snd_be