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Date: Sun, 31 May 2009 16:03:54 +0200
From: Olivier Galibert <galibert@pobox.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: paul@mad-scientist.net, linux-kernel@vger.kernel.org, stable@kernel.org,
       Andrew Morton <akpm@linux-foundation.org>,
       Andi Kleen <andi@firstfloor.org>, Oleg Nesterov <oleg@redhat.com>,
       Roland McGrath <roland@redhat.com>
Subject: Re: [PATCH] coredump: Retry writes where appropriate
Message-ID: <20090531140354.GA92675@dspnet.fr.eu.org>
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	Alan Cox <alan@lxorguk.ukuu.org.uk>, paul@mad-scientist.net,
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	Andrew Morton <akpm@linux-foundation.org>,
	Andi Kleen <andi@firstfloor.org>, Oleg Nesterov <oleg@redhat.com>,
	Roland McGrath <roland@redhat.com>
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On Sun, May 31, 2009 at 11:18:51AM +0100, Alan Cox wrote:
> On Sun, 31 May 2009 01:33:39 -0400
> Paul Smith <paul@mad-scientist.net> wrote:
> 
> > coredump: Retry writes where appropriate
> > 
> > Core dump write operations (especially to a pipe) can be incomplete due
> > to signal reception or possibly recoverable partial writes.
> 
> NAK this
> 
> > Previously any incomplete write in the ELF core dumper caused the core
> > dump to stop, giving short cores in these cases.  Modify the core dumper
> > to retry the write where appropriate.
> 
> The existing behaviour is an absolute godsend when you've something like
> a core dump stuck on an NFS mount or something trying to core dump to
> very slow media.
> 
> In fact the signals checks were *purposefully added* some time ago.

Perhaps removing the "|| r == -EINTR" part would make both of you
happy?  He gets the reliability on pipes, you keep the interrupt on
signals.

  OG.