Re: [PATCH] VT-d: improve RMRR validity checking

[Weidong Han <weidong.han@intel.com>]

Noboru Iwamatsu wrote:
> Hi Weidong,
>
> I re-send the DRHD-fix patch.
>
> If DRHD does not have existent devices, ignore it.
> If DRHD has both existent and non-existent devices, consider it invalid
> and not register.
>   

Although you patch workarounds your buggy BIOS, but we still need to 
enable it for security purpose as I mentioned in previous mail. We 
needn't workaround / fix all BIOS issues in software. I think security 
is more important for this specific BIOS issue. Did you report the BIOS 
issue to your OEM vendor? maybe it's better to get it fixed in BIOS.

Regards,
Weidong
> According to this patch and yours, my machine successfully booted
> with vt-d enabled.
>
> Signed-off-by: Noboru Iwamatsu <n_iwamatsu@jp.fujitsu.com>
>
>
>   
>> Keir Fraser wrote:
>>     
>>> On 21/01/2010 10:19, "Weidong Han" <weidong.han@intel.com> wrote:
>>>
>>>       
>>>>> Sorry this is typo.
>>>>> I mean:
>>>>> So, I think RMRR that has no-existent device is "invalid"
>>>>> and whole RMRR should be ignored.
>>>>>           
>>>> looks reasonable.
>>>>
>>>> Keir, I Acks Noboru's rmrr patch. Or do you want us to merge them to one
>>>> patch?
>>>>         
>>> Merge them up, re-send with both sign-off and acked-by all in one email.
>>>
>>> Thanks,
>>> Keir
>>>
>>>       
>> Sorry, I disagree with Noboru after thinking it again. If the RMRR has
>> both no-existent device and also has existent devices in its scope, we
>> should not ignore it because the existent devices under its scope will
>> be impacted without the RMRR. so I suggest to print a warning instead of
>> ignore it. Attached a patch for it.
>>
>> Signed-off-by: Weidong Han <weidong.han@intel.com>
>>     
>
>