Re: [PATCH 1/2] pci: release that leaf bridge' resource that is not big -v11

[Yinghai <yinghai@kernel.org>]

On Nov 25, 2009, at 10:43 PM, Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com 
 > wrote:

> Yinghai Lu wrote:
>> Kenji Kaneshige wrote:
>>> Hi Yinghai,
>>>
>>> I would like to reconfirm what is the problem you're trying to solve
>>> before reviewing and testing the additional patch. To be honest,  
>>> your
>>> patch looks more and more complicated and it is becoming difficult
>>> for me to review and test it.
>> the real problem:
>> 1. boot time:
>> BIOS separate IO range between several IOHs, and on some slots,  
>> BIOS assign the resource to the bridge, but stop
>> assigning resource to the device under that bridge, because the  
>> device need big resource.
>> so patch1 is trying to a. pci assign unassign and record the failed  
>> device resource.
>> b. clear the BIOS assigned resource of the parent bridge of fail  
>> device
>> c. go back and call pci assign unsigned
>> d. if it still fail, will go up more bridges. and clear and try  
>> again.
>> 2. hotplug:
>> BIOS separate IO range between several IOHs, and on some slots,  
>> BIOS assign the resource to every bridge. (8M)
>> but when insert one card that big resource, the card can not get  
>> resource. because kernel will not touch the bridge resource.
>> so patch2 is trying to
>> a. assign resource to devices with that slot. and record fail devices
>> b. if there is some failed, will clear sepcifically io port of  
>> bridge, or mmio of bridge, or mmio pref of bridge.
>> c. try to assign the parent bridge of the slot.
>> so it will keep original assigned resource by BIOS if possible.
>> and you have tested patch1 and patch2 in V11, but said patch1 may  
>> have shrinking resource problem.
>> the patch3 is addressing the patch1 that could shrinking resource  
>> for non-pcie hotplug bridge...
>>
>
> Thank you for the explanation. The patch3 seems to solve my concern.
>
> Your patch only touch the leaf bridge at the 2nd try of resource
> assignment. IIRC, this behavior is to prevent from shrinking bridge
> resources. Am I correct? I'm not sure but I think we don't need this
> behavior because now that we have another mechanism to prevent
> from shrinking bridge resource.
>>>

Third patch will only try to increase the bridge res

Try num still default to 5 , it could help other case

Can you send me whole bootlog  ?

Thanks

Yinghai