From mboxrd@z Thu Jan  1 00:00:00 1970
From: tytso@mit.edu
Subject: Re: [RFC 1/1] fs/reiserfs/journal.c: Remove obsolete  __GFP_NOFAIL
Date: Wed, 26 Mar 2014 02:19:04 -0400
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To: David Rientjes <rientjes@google.com>
Cc: Dave Jones <davej@redhat.com>, Andrew Morton <akpm@linux-foundation.org>, Fabian Frederick <fabf@skynet.be>, linux-kernel <linux-kernel@vger.kernel.org>, reiserfs-devel@vger.kernel.org, Joe Perches <joe@perches.com>

On Tue, Mar 25, 2014 at 06:06:17PM -0700, David Rientjes wrote:
> 
> The point is not to add new callers and new code should handle NULL 
> correctly, not that we should run around changing current users to just do 
> infinite retries.  Checkpatch should have nothing to do with that.

My problem with this doctrinaire "there should never be any new users"
is that sometiems there *are* worse things than infinite retries.  If
the alternative is bringing the entire system down, or livelocking the
entire system, or corrupting user data, __GFP_NOFAIL *is* the more
appropriate option.

If you try to tell those of us outside of the mm layer, "thou shalt
never use __GFP_NOFAIL in new code", and we have some new code where
the alternative is worse, we can either open-code the loop, or have
some mm hackers and/or checkpatch whine at us.

Andrew has declared that he'd prefer that we not open code the retry
loop; if you want to disagree with Andrew, feel free to pursuade him
otherwise.  If you want to tell me that I should accept user data
corruption, I'm going to ignore you (and/or checkpatch).

Regards,

						- Ted