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Date: Fri, 21 Dec 2018 13:07:12 +0300
From: Alexey Dobriyan <adobriyan@gmail.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: =?utf-8?B?TWljaGHFgiBNaXJvc8WCYXc=?= <mirq-linux@rere.qmqm.pl>,
        linux-fsdevel@vger.kernel.org, David Rientjes <rientjes@google.com>
Subject: Re: [PATCH 1/2] procfs: signal /proc/PID/comm write truncation
Message-ID: <20181221100712.GA2106@avx2>
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On Thu, Dec 20, 2018 at 12:38:33PM -0800, Andrew Morton wrote:
> On Thu, 20 Dec 2018 00:28:04 +0100 Michał Mirosław <mirq-linux@rere.qmqm.pl> wrote:
> 
> > Keeps truncation working, but also signals to writing process
> > when that happens.
> 
> Please fully describe what is presently wrong with truncation.  ie:
> describe the end-user-visible effects of a bug when fixing it.

Well, patch returns number of bytes actually copied instead of what
write(2) is given if truncation occurs.

But TASK_COMM_LEN was fixed since forever, none of this is needed.

Same for the second patch, lseek(SEEK_END) is unnecessary is
the size of the file is fixed.