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Date:   Fri, 1 May 2020 22:30:48 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     Christoph Hellwig <hch@lst.de>, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] exec: open code copy_string_kernel
Message-ID: <20200501213048.GO23230@ZenIV.linux.org.uk>
References: <20200501104105.2621149-1-hch@lst.de>
 <20200501104105.2621149-3-hch@lst.de>
 <20200501141903.5f7b1f81fdd38ae372d91f0e@linux-foundation.org>
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On Fri, May 01, 2020 at 02:19:03PM -0700, Andrew Morton wrote:
> On Fri,  1 May 2020 12:41:05 +0200 Christoph Hellwig <hch@lst.de> wrote:
> 
> > Currently copy_string_kernel is just a wrapper around copy_strings that
> > simplifies the calling conventions and uses set_fs to allow passing a
> > kernel pointer.  But due to the fact the we only need to handle a single
> > kernel argument pointer, the logic can be sigificantly simplified while
> > getting rid of the set_fs.
> > 
> 
> I don't get why this is better?  copy_strings() is still there and
> won't be going away - what's wrong with simply reusing it in this
> fashion?
> 
> I guess set_fs() is a bit hacky, but there's the benefit of not having
> to maintain two largely similar bits of code?

Killing set_fs() would be a very good thing...