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Subject: Re: [clang] NMI while trying to read acpi timer register
From: Adrian Chadd <adrian@freebsd.org>
To: Andriy Gapon <avg@freebsd.org>
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On 30 January 2013 13:03, Andriy Gapon <avg@freebsd.org> wrote:
> on 28/01/2013 16:30 Andriy Gapon said the following:
>> is there any reasonable explanation for getting an NMI while trying to read acpi
>> timer register?
>> Note: this happens only after ACPI suspend/resume.
>
> An update.
> This happens only with clang compiled kernel, gcc compiled kernel is OK.
> Also, this happens only in the depth of fwohci driver (where it calls DELAY).
> If firewire is not loaded, then there is no problem.
>
> I suspect that perhaps there is some miscompilation that results in some
> incorrect I/O access that later leads to NMI.  Too many unknowns and guesses
> here, obviously.

Do you have stack traces showing where it's happening?

Posting that and the disassembly from those areas may shed a clue.



Adrian