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Date: Fri, 12 Jun 2009 13:55:18 -0400
From: Theodore Tso <tytso@mit.edu>
To: Ingo Molnar <mingo@elte.hu>
Cc: Wu Fengguang <fengguang.wu@intel.com>,
       Thomas Gleixner <tglx@linutronix.de>, "H. Peter Anvin" <hpa@zytor.com>,
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       "linux-mm@kvack.org" <linux-mm@kvack.org>,
       Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH 1/5] HWPOISON: define VM_FAULT_HWPOISON to 0 when
	feature is disabled
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On Fri, Jun 12, 2009 at 05:36:20PM +0200, Ingo Molnar wrote:
> > The data corruption has not caused real hurt yet, and can be 
> > isolated to prevent future accesses.  So it makes sense to just 
> > kill the impacted process(es).
> 
> Dunno, this just looks like a license to allow more crappy hardware, 
> hm? I'm all for _logging_ errors, but hwpoison is not about that: it 
> is about allowing the hardware to limp along in 'enterprise' setups, 
> with a (false looking) 'guarantee' that everything is fine.

This should be tunable; in some cases, logging it is the right thing
to do; I imagine that in the case of the desktop OS, the user would
appreciate being given *some* chance to save the document he or she
has spent the past hour working on before the system goes down "hard
and fast".

In other cases, the sysadmin is using a high-availability setup in an
enterprise deployment, and there he or she would want the system to
immediately shutdown so the hot standby can take over.

	    	     	    		    	 - Ted