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From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Subject: Re: [PATCH] libata: add warning about possible HPA compatibility issue
Date: Tue, 26 May 2009 01:15:00 +0200
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       linux-kernel@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>
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On Tuesday 26 May 2009 00:38:14 Alan Cox wrote:
> > > NAK - this is extremely misleading and will just randomly terrify users,
> > > who may then set the paramater and corrupt things like BIOS save areas.
> > 
> > Please propose better description.
> 
> As was discussed before
> 
> Tejun has a patch in the queue which exposes the HPA and real sizes to
> the OS

In queue for 2.6.30?

> Libata can support revalidating a disc
> 
> Once the HPA/Real size data is there the tools can be tuned for this and
> a sysfs node added to switch hpa on/off per disc. At that point this can
> be done by the user space intelligently.

Unless you happen to have partition with tools in HPA area etc.

Also care to post link to the existing user-space tools with added HPA
support and documentation how to use them so I can start pointing people
reporting problems in this direction?

> The fact this is a user parameter is itself a problem.

Yes.  It is a problem but we can't reverse the history.

I fully agree w.r.t to proper handling of HPA but we need "something" in
the meantime because it is *real* issue resulting in *real* users filling
*real* bug-reports (which unfortunately always get assigned to me first
so I'm needlessly wasting my time on them).

IOW Please stop downplaying bug #13365 which this patch tries to alleviate.

I'm adding Andrew to cc:...