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Date: Wed, 14 Feb 2007 15:40:14 +0000
From: Alan <alan@lxorguk.ukuu.org.uk>
To: "Jan Beulich" <jbeulich@novell.com>
Cc: <alan@redhat.com>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH, RFC] adjust legacy IDE resource setting
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On Wed, 14 Feb 2007 15:05:24 +0000
"Jan Beulich" <jbeulich@novell.com> wrote:

> The change to force legacy mode IDE channels' resources to fixed
> non-zero values confuses (at least some versions of) X, because the
> values reported by the kernel and those readable from PCI config space
> aren't consistent anymore. Therefore, this patch arranges for the
> respective BARs to also get updated if possible.

If X is getting confused fix X. Those BARs are *undefined* in legacy
mode. The value in them is undefined, the results that end up there if
you do write to them are undefined too. If X believes those BAR values
blindly it'll do the wrong thing in some freaky cases.

Which specific versions of X are problematic ?

As to the implementation:
	start and end as passed are the real I/O values so you don't need
to mask them that I can see.

I've no fundamental problem with writing the BAR values back to avoid
confusing some apparently broken X, but I'd like to know what X, what
circumstances and that X is also getting fixed.

Alan