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Date:   Thu, 29 Apr 2021 12:07:44 +0200
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     "Arkadiusz Kozdra (Arusekk)" <arek_koz@o2.pl>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Christoph Hellwig <hch@lst.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-fsdevel@vger.kernel.org,
        Alexey Dobriyan <adobriyan@gmail.com>,
        Al Viro <viro@zeniv.linux.org.uk>
Subject: Re: [PATCH v2] proc: Use seq_read_iter for /proc/*/maps
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 <20210429100508.18502-1-arek_koz@o2.pl>
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On Thu, Apr 29, 2021 at 12:05:08PM +0200, Arkadiusz Kozdra (Arusekk) wrote:
> Since seq_read_iter looks mature enough to be used for /proc/<pid>/maps,
> re-allow applications to perform zero-copy data forwarding from it.
> 
> Some executable-inspecting tools rely on patching entry point
> instructions with minimal machine code that uses sendfile to read
> /proc/self/maps to stdout.  The sendfile call allows them to do it
> faster and without excessive allocations.

What programs do that today?  You might want to list them here.

> 
> This is inspired by the series by Cristoph Hellwig (linked).
> 
> Changes since v1:
> 
> only change proc_pid_maps_operations

This should go below the --- line, like the documentation states.

thanks,

greg k-h