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Date: Tue, 20 Mar 2012 23:03:53 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Daniel Kurtz <djkurtz@chromium.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        Joonyoung Shim <jy0922.shim@samsung.com>,
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        linux-kernel@vger.kernel.org, Benson Leung <bleung@chromium.org>,
        Yufeng Shen <miletus@chromium.org>
Subject: Re: [PATCH 06/20] Input: atmel_mxt_ts - allow writing to object
 sysfs entry
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On Tue, 13 Mar 2012 20:04:09 +0800
Daniel Kurtz <djkurtz@chromium.org> wrote:

> Userspace can write a 24-bit value (encoded as a 6 character hex string)
> to the 'object' sysfs entry to modify a single byte of the object table.
> The hex string encodes a 3 bytes, in the following format:

How is this locked against other users and updates of these table data ?

I don't see how all the objects and their pointers and size are
guaranteedto always be valid in all the users you have ?