[CentOS] Warning: Your BIOS is broken

[m.roth at 5-cent.us]

Robert Moskowitz wrote:
>
> On 02/22/2013 01:38 PM, John R Pierce wrote:
>> On 2/21/2013 12:43 PM, Robert Moskowitz wrote:
>>> :[Firmware Warn]: Your BIOS is broken; DMAR reported at address
>>> fed90000
>>> returns all ones!
>> I googled "Your BIOS is broken; DMAR reported at address fed90000
>> returns all ones!" and got some related results.
>
> My search fu was weak.  Very weak.
>
>> this bug report (on FC12) says...  "yes, your bios is broken, but its
>> not a bug, we worked around it"
>> https://bugzilla.redhat.com/show_bug.cgi?id=896652
>
> Well since Centos 6 is about equiv to F12, I guess I can 'live' with
> claim.  But then, how to stop the constant error reporting?
>
>> on a similar/identical bug with Fedora FC17, someone suggested booting
>> with iommu=off to work around this.
>
> Where do I add this?

On the kernel line in grub.conf

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