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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Thu, 24 Sep 2020 09:41:28 +0200
Message-ID: <CAK8P3a3HWjyaxwN3gyFEcJ9P=iHPvYXsL=C2kEg1hDmJvNm1tQ@mail.gmail.com>
Subject: Re: [RFC PATCH 8/9] surface_aggregator: Add DebugFS interface
To:     Maximilian Luz <luzmaximilian@gmail.com>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        =?UTF-8?Q?Bla=C5=BE_Hrastnik?= <blaz@mxxn.io>,
        Dorian Stoll <dorian.stoll@tmsp.io>
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On Thu, Sep 24, 2020 at 12:23 AM Maximilian Luz <luzmaximilian@gmail.com> wrote:
> On 9/23/20 8:51 PM, Arnd Bergmann wrote:
> > On Wed, Sep 23, 2020 at 8:29 PM Maximilian Luz <luzmaximilian@gmail.com> wrote:
> >> On 9/23/20 6:48 PM, Arnd Bergmann wrote:
> >
> > The version I showed avoids the pointers and is compatible with
> > 32-bit user space.
>
> I'm not completely convinced yet that the read/write approach is the way
> I want to do it, especially with Greg suggesting a misc device, but I'll
> keep your solution in mind.

In case of a character device, I'd go with an ioctl to keep it extensible.

The read/write based interface is what I'd use in debugfs.

      Arnd