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From:   Sven Van Asbroeck <thesven73@gmail.com>
Date:   Mon, 15 Feb 2021 10:54:25 -0500
Message-ID: <CAGngYiWxMsko2+6NUt4N0GyBUq4Axz4TRiUrF2ZjNGvZZkTO8A@mail.gmail.com>
Subject: Re: [BUG REPORT] media: coda: mpeg4 decode corruption on i.MX6qp only
To:     Lucas Stach <l.stach@pengutronix.de>
Cc:     Philipp Zabel <pza@pengutronix.de>,
        Nicolas Dufresne <nicolas@ndufresne.ca>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Adrian Ratiu <adrian.ratiu@collabora.com>,
        Fabio Estevam <festevam@gmail.com>,
        linux-media <linux-media@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Hi Lucas,

On Mon, Feb 15, 2021 at 5:15 AM Lucas Stach <l.stach@pengutronix.de> wrote:
>
> The straight forward way to fix this would be to just disable the PRE
> when the stride is getting too large, which might not work well with
> all userspace requirements, as it effectively disables the ability to
> scan GPU tiled surfaces when the stride is getting too large.

Thank you for your very knowledgeable input, really appreciate it.

I am wondering why I am the first to notice this particular corner
case. Is this perhaps because X+armada plugin allocate a huge bitmap
that fits all displays, and other software frameworks do not? Are
people on i.MX6 mostly using X or Wayland? If Wayland allocates a
separate bitmap for each display, this PRE bug will of course never
show up...

Sven