Re: [PATCH v2] vpci: add permission checks to map_range()

[Jan Beulich <jbeulich@xxxxxxxx>]

On 27.07.2023 13:07, Daniel P. Smith wrote:
> 
> 
> On 7/27/23 03:56, Jan Beulich wrote:
>> On 26.07.2023 16:01, Roger Pau Monne wrote:
>>> Just like it's done for the XEN_DOMCTL_memory_mapping hypercall, add
>>> the permissions checks to vPCI map_range(), which is used to map the
>>> BARs into the domain p2m.
>>>
>>> Adding those checks requires that for x86 PVH hardware domain builder
>>> the permissions are set before initializing the IOMMU, or else
>>> attempts to initialize vPCI done as part of IOMMU device setup will
>>> fail due to missing permissions to create the BAR mappings.
>>>
>>> While moving the call to dom0_setup_permissions() convert the panic()
>>> used for error handling to a printk, the caller will already panic if
>>> required.
>>>
>>> Fixes: 9c244fdef7e7 ('vpci: add header handlers')
>>> Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
>>
>> I've committed this, but despite the Fixes: tag I'm not sure this
>> wants backporting. Thoughts?
> 
>  From a cursory review thus far, since this introduced a new XSM hook 
> site, shouldn't this have at least had an Rb by an XSM 
> reviewer/maintainer?

Probably, but already back then I said this model isn't going to work
flawlessly.

> I would have replied sooner, but have been on holiday for last two weeks.

I guess there was no way for us to know without you sending a note to
private@ (which, I will admit, you may not even have been aware of).

Jan