Re: [PATCH] vpci/msix: restore PBA access length and alignment restrictions

[Jan Beulich <jbeulich@xxxxxxxx>]

On 29.03.2023 16:20, Roger Pau Monné wrote:
> On Wed, Mar 29, 2023 at 03:22:34PM +0200, Jan Beulich wrote:
>> On 29.03.2023 12:18, Roger Pau Monne wrote:
>>> @@ -419,9 +424,8 @@ static int adjacent_write(const struct domain *d, const 
>>> struct vpci_msix *msix,
>>>       * assumed to be equal or bigger (8 bytes) than the length of any 
>>> access
>>>       * handled here.
>>>       */
>>> -    if ( (VMSIX_ADDR_IN_RANGE(addr, vpci, VPCI_MSIX_PBA) ||
>>> -          VMSIX_ADDR_IN_RANGE(addr + len - 1, vpci, VPCI_MSIX_PBA)) &&
>>> -         !is_hardware_domain(d) )
>>> +    if ( VMSIX_ADDR_IN_RANGE(addr, vpci, VPCI_MSIX_PBA) &&
>>> +         (!access_allowed(msix->pdev, addr, len) || 
>>> !is_hardware_domain(d)) )
>>>          /* Ignore writes to PBA for DomUs, it's undefined behavior. */
>>>          return X86EMUL_OKAY;
>>
>> While preparing the backport, where I'm folding this into the earlier
>> patch, I've noticed that this change has now left the comment stale
>> (the problematic part if just out of context). Not sure though whether
>> that's worth yet another fixup patch.
> 
> I see, thanks for noticing.  I think I can likely adjust in some further 
> change,
> or even just drop it, not sure the comment is that relevant anymore if both 
> the
> PBA and the access must be aligned now.

Yeah, dropping would be fine with me. Plus you're the maintainer anyway ...

Jan