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Re: [Xen-devel] [Patch] [RFC] avoid debugger_trap when we don't expect

To: Akio Takebe <takebe_akio@xxxxxxxxxxxxxx>, xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>, xen-ia64-devel <xen-ia64-devel@xxxxxxxxxxxxxxxxxxx>, xen-ppc-devel <xen-ppc-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] [Patch] [RFC] avoid debugger_trap when we don't expect
From: Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>
Date: Wed, 30 Jan 2008 09:26:32 +0000
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On 30/1/08 08:48, "Akio Takebe" <takebe_akio@xxxxxxxxxxxxxx> wrote:

>> This doesn't need to be fixed on x86 -- the int3 handler will return
>> silently if the debugger is not configured. It would be nice if the ia64
>> handler would do the same. If that is not possible then change only ia64
>> code and if you need to be able to probe gdbstub configuration then add a
>> public function to do that rather than grope at internal state. The same
>> goes for powerpc, *if* it is broken in the first place.
> I know the int3 hanlder return well on x86 if it is not configured.
> But the route may be not safe. The debugger_trap is called after hypervisor
> panic and dom0 panic. So I want to avoid the needless route for kexec/kdump.

Oh no, then all bets are off. :-) We could be screwed and fail to kexec no
matter what we do.

 -- Keir

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