From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keith Owens <kaos@sgi.com>
Date: Wed, 13 Mar 2002 05:22:45 +0000
Subject: Re: [Linux-ia64] Exception handling and recovery
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To: linux-ia64@vger.kernel.org

On Tue, 12 Mar 2002 20:51:13 -0800, 
David Mosberger <davidm@napali.hpl.hp.com> wrote:
>>>>>> On Wed, 13 Mar 2002 14:53:31 +1100, Keith Owens <kaos@sgi.com> said:
>
>  Keith> Unlike i386, the ia64 exception table code only recovers from
>  Keith> invalid user space addresses.  kdb can get other faults which
>  Keith> EX() does not currently allow recovery from.  Is there any
>  Keith> reason why I should not add exception table handling to
>  Keith> ia64_fault(), to generalize the fault recovery mechanism?
>
>You mean kdb would do get_user() on a bad pointer, which triggers
>ia64_fault() and then you want to search the exception table in
>ia64_fault()?  I think it would be ok to do this (in the KDB patch).

Exactly.  IMHO ia64_fault should always search_exception_table(), even
if kdb is not installed.  Other architectures use exception tables to
detect if the hardware supports extra instructions, registers, MSR
values etc., exception recovery should be general purpose.