Re: [PATCH v2 5/9] ACPI/pci-bind: remove bind/unbind callbacks from acpi_device_ops

[Yinghai Lu <yinghai@kernel.org>]

On Mon, Sep 17, 2012 at 7:31 AM, Jiang Liu <liuj97@gmail.com> wrote:
> On 09/16/2012 07:27 AM, Yinghai Lu wrote:
>>> --- a/drivers/acpi/scan.c
>>> +++ b/drivers/acpi/scan.c
>>> @@ -1232,17 +1232,8 @@ static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
>>>         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
>>>         device_release_driver(&dev->dev);
>>>
>>> -       if (!rmdevice)
>>> -               return 0;
>>> -
>>> -       /*
>>> -        * unbind _ADR-Based Devices when hot removal
>>> -        */
>>> -       if (dev->flags.bus_address) {
>>> -               if ((dev->parent) && (dev->parent->ops.unbind))
>>> -                       dev->parent->ops.unbind(dev);
>>> -       }
>>> -       acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
>>> +       if (rmdevice)
>>> +               acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
>>>
>>>         return 0;
>>>  }
>>
>> for pci root bus, acpi_bus_trim() is used to remove acpi_device.
>>
>> and later in acpi_pci_root_remove to stop pci drivers/ioapic driver,
>> iommu driver then remove pci devices.
>>
>> if call back is removed there, then could some functions in
>> acpi_pci_unbind() will be skipped.
>>
>> I really do not want to add pci_stop_bus_devices() in
>> pci_root_hp.c::handle_root_bridge_removal before
>> calling acpi_bus_trim...
> Hi Yinghai,
>         We are working on a ACPI based hotplug framework for CPU, memory and IOH.
> With our framework, the sequence to remove a IOH is:
> 1) unbind all PCI device drivers for affected PCI devices.
> 2) stop and remove all affected PCI devices.
> 3) stop ACPI ioapic drivers(a new driver like PCI version).
> 4) destroy all ACPI devices.

i solved the problem...

http://git.kernel.org/?p=linux/kernel/git/yinghai/linux-yinghai.git;a=commitdiff;h=15967ed108f9543c160422a7aaec18de30a53373

+       if (!acpi_bus_get_device(handle, &device)) {
+               int ret_val;
+
+               /* remove pci devices at first */
+               ret_val = acpi_bus_trim(device, 0);
+               printk(KERN_DEBUG "acpi_bus_trim stop return %x\n", ret_val);
+
+               /* remove acpi devices */
+               ret_val = acpi_bus_trim(device, 1);
+               printk(KERN_DEBUG "acpi_bus_trim remove return %x\n", ret_val);
+       }

...

also need to update acpi_bus_trim

http://git.kernel.org/?p=linux/kernel/git/yinghai/linux-yinghai.git;a=commitdiff;h=c8805fe6ec46c46f352cdbffb13191116ea794ba

BTW, memory hot-remove may need some work.

Thanks

Yinghai