From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: Xen 4.0 crashes with pvops kernel
Date: Tue, 15 Jun 2010 13:56:23 +0100
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To: Jan Beulich <JBeulich@novell.com>, Cris Daniluk <cris.daniluk@gmail.com>
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On 15/06/2010 13:50, "Jan Beulich" <JBeulich@novell.com> wrote:

> But even if we verify that the references come from some ACPI
> method(s), likely the only way to address this is to fix the kernel
> side error handling.
> 
> Keir, assuming these are reads only, would it make sense to permit
> Dom0 to map the IO-APIC space read-only? Perhaps even
> transparently converting writeable mappings to read-only ones
> (since drivers/acpi/osl.c tries to establish writeable mappings
> irrespective of the actual needs)? The obvious danger in doing
> so is that going forward there may appear fields in that page
> reads of which aren't side effect free...

Well, how come it works with other Linux kernels -- presumably they have
some extra error handling in the ACPI subsystem? Shouldn't that just be
added to this kernel?

 -- Keir