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

To: Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>, xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>, xen-ia64-devel <xen-ia64-devel@xxxxxxxxxxxxxxxxxxx>, xen-ppc-devel <xen-ppc-devel@xxxxxxxxxxxxxxxxxxx>
Subject: [XenPPC] Re: [Xen-devel] [Patch] [RFC] avoid debugger_trap when we don't expect
From: Akio Takebe <takebe_akio@xxxxxxxxxxxxxx>
Date: Thu, 31 Jan 2008 09:56:00 +0900
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Hi, Keir

>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.
OK. I just suggested a safer way than current code.
Recently we found a bug around the trap handler on ia64,
so I worry about such a thing.
I still want to avoid the needless code on ia64.
so I'll talk in xen-ia64 ML.

Best Regards,

Akio Takebe

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