Re: [PATCH resend v2] Extending kernel option pci=resource_alignment to be able to specify PCI device/vendor IDs

[Yongji Xie <xyjxie@linux.vnet.ibm.com>]

Hi Mathias,


On 2016/7/25 14:05, Koehrer Mathias (ETAS/ESW5) wrote:
> Hi Gavin,
>
>> Mathias, The code change would conflict with Yongji's patch where the
>> wildcard introduced to identify PCI devices.
>>
>> https://patchwork.ozlabs.org/patch/642473/
> That's true, however it is also true the other way round. The first sending of my patch was
> 22-June 2016 and thus before Yongji's patch...
> See also the comment of Bjorn Helgaas on my patch (v1):
> http://marc.info/?l=linux-pci&m=146654644431550&w=2
>
> However it looks as if there are a couple of (conflicting) approaches for the issue with the alignment of PCI addresses flying around...
> My personal opinion is that the need to adapt the alignment of PCI addresses should be done on PCI device/vendor ids of relevant PCI devices and not on PCI addresses.
> The PCI addresses are likely to change e.g. by inserting another PCI board. The device/vendor id of the devices will not change.

Yes, your opinion is right. I think I will update my patches based on 
your change.

With your patch, seems like we can specify alignment for all PCI devices 
by using something like: pci=resource_alignment=4096@pci:0:0.
We'd better document it.

Thanks,
Yongji