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Date: Wed, 6 Aug 2014 15:48:33 +0100
From: Matt Fleming <matt@console-pimps.org>
To: Eric van Gyzen <eric@vangyzen.net>
Subject: Re: Sanity Check:  Bogus(?) General Protection Fault
Message-ID: <20140806144833.GE15082@console-pimps.org>
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On Wed, 06 Aug, at 10:12:06AM, Eric van Gyzen wrote:
> Can someone give me a quick sanity check?  I'm debugging a General
> Protection Fault on an amd64 system.  The faulting instruction appears
> to be an immediate mov into %r11...right?  I ask because I can't imagine
> how that instruction could cause a GPF.  Any ideas?
> 
> Thanks,
> 
> Eric
> 
> ====
> 
> Fatal trap 9: general protection fault while in kernel mode
> cpuid = 0; apic id = 00
> instruction pointer     = 0x20:0xffffffff805d6e23

[...]

> 0xffffffff805d6e23 <vm_reserv_alloc_contig+947>:    mov   %rcx,0x10(%r11,%r9,1)

This is your faulting instruction.

-- 
Matt Fleming, Intel Open Source Technology Center