Re: RE: xl fails to work with some command

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

Stefano Stabellini wrote:
> On Thu, 26 Aug 2010, Konrad Rzeszutek Wilk wrote:
>   
>> On Thu, Aug 26, 2010 at 01:17:08PM +0100, Stefano Stabellini wrote:
>>     
>>> On Thu, 26 Aug 2010, Weidong Han wrote:
>>>       
>>>> Stefano Stabellini wrote:
>>>>         
>>>>> On Mon, 23 Aug 2010, Zhang, Yang Z wrote:
>>>>>   
>>>>>           
>>>>>>>> 6.  vcpu-set is not supported by xl. So some RAS case which use xl vcpu-set
>>>>>>>>         
>>>>>>>>                 
>>>>>>> to set guest's cpu set will fails. case "vcpu_hot_add_64_g32e" fails.
>>>>>>>       
>>>>>>> actually vcpu-set is supported by xl, have you found any bugs using it?
>>>>>>>       
>>>>>>>               
>>>>>> For pv guest, it work well. But for HVM guest, xl miss some function about cpu hotplug which was added recently.
>>>>>>
>>>>>> xl seems only support FLR and didn't support Second Bus Reset and D0/D3. Will you add them in xl?
>>>>>>     
>>>>>>             
>>>>>  
>>>>> xl uses the sysfs "reset" node provided by the pci subsystem of the
>>>>> Linux kernel, that should support Secondary Bus Reset and D0/D3 already.
>>>>>   
>>>>>           
>>>> Do you mean xl uses Linux kernel PCI API (i.e. pci_reset_function) to 
>>>> reset PCI device?
>>>>         
>>> Yes, give a look at libxl_device_pci_reset: first libxl tries to use the
>>> pciback sysfn node "do_flr", but if it is not present it will use the
>>> standard linux sysfs "reset" node.
>>> Please note that on pvops kernels the do_flr node is not present (but it
>>> is present on both XCP and XCI kernels) while the reset node points to
>>> pci_reset_function.
>>>       
>> <hint>I am all up for receiving the patches from XCP/XCI for this</hint>
>>
>>     
>
> I think that using the standard linux reset mechanism is a better way to
> handle this as oppose to have our own do_flr method.
>   
Pls note that there are some specific FLR functions for graphics 
pass-through. They should be ported to xl.

Regards,
Weidong