Re: [Qemu-devel] [Issues] PCI hotplug does not work well on pc platform?

["Liu, Jing2" <jing2.liu@linux.intel.com>]

Hi Marcel and Igor,

Thanks very much for your help!

On 2/14/2019 10:42 PM, Marcel Apfelbaum wrote:
> 
> 
[...]
>>>>>>> I have two questions.
>>>>>>> 1. PCI hotplug on pci.0 must manually rescan in guest. The ACPI 
>>>>>>> hotplug
>>>>>>> handler sends the GPE event to guest but it seems guest doesn't 
>>>>>>> receive
>>>>>>> it? I tried to open ACPI debug level/layer to 0xffffffff, in 
>>>>>>> order to
>>>>>>> see if there is any message after device_add in monitor, but no 
>>>>>>> message
>>>>>>> comes out until I manually rescan. Also tried printk in
>>>>>>> acpi_ev_gpe_xrupt_handler() and acpi_ev_sci_xrupt_handler(). No 
>>>>>>> output
>>>>>>> in dmesg.
>>>>>>> (I'm sure that CONFIG_HOTPLUG_PCI_PCIE=y, CONFIG_HOTPLUG_PCI_CPCI=y,
>>>>>>> CONFIG_HOTPLUG_PCI=y, CONFIG_HOTPLUG_PCI_ACPI=y)
>>> What about |CONFIG_HOTPLUG_PCI_SHPC=y ?
>>>

Thanks and I finally found it is because I set hardware reduced acpi 
before and now it is correct.

>>> |
>>>>>>> Whether this is a kind of design or a known issue? Does guest 
>>>>>>> receive
>>>>>>> the request, where can I find the
>>>>>> does it work with known to work kernels (RHEL7)?
>>>>>>
>>>>>> Also sharing used QEMU version and command line could help.
>>>>> Is there any key config of kernel in guest, besides those I listed 
>>>>> above?
>>>> Maybe Marcel knows something about it
>>>> (CCed)
>>> May I ask why do you need SHPC hotplug and not the ACPI based hotplug?
Oh, it is some customer's requests. And the method to set PIIX4_PM 
property works.


Thanks!
Jing