Re: [PATCH 0/7] Fixups for duplicate slot names

Kenji Kaneshige
2008-08-07T08:44:27Z

Hi Alex-san,

Thank you for patches!

I looked at your patches and it looks good. But I have only one
concern about how to allocate/free memory for slot name.

With your change, memory region for slot name will be allocated
by hotplug *controller* driver and it can be freed using kfree()
by hotplug *core* driver (not hotplug controller driver). So all
hotplug controller drivers including drivers implemented in the
future need to take it into account.

I think it will be more robust if we can allocate and free memory
in the same component (maybe hotplug core driver in this case).

Thanks,
Kenji Kaneshige

Alex Chiang wrote:
> * Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>:
>> With this change, kobject_init_and_add() called in
>> pci_create_slot() will show stack trace if a hotplug driver
>> attempts to register multiple slot with the same name. That is,
>> stack trace will be shown on the platform that wrongly assing
>> the physical slot number to multiple slots. I'm very sorry, but
>> I don't have enough time to consider how to fix it today.
>
> Hello Kenji-san,
>
> You are obviously correct about my prior bad patch that simply
> removed the check in pci_hp_register() for duplicate names.
>
> I also talked with Willy, and he thought that the proper way to
> fix all these issues was not in the individual drivers, but in
> the PCI core, which I agree with.
>
> Here is a patch series that attempts to implement Willy's
> suggestion.
>
> Patches 1--6 convert the callers of pci_hp_register/pci_create_slot
> from a static char name[] to a dynamically kmalloc'ed char *name.
>
> There are also cleanups in the individual drivers to remove the
> _slot_with_bus parameters.
>
> Patch 7/7 implements the collision rename logic. It's not the
> prettiest thing in the world, so your comments are welcome. :)
>
> It's getting late here and I haven't had time to really test it,
> other than a quick compile test, but I wanted to try and send it
> so that you could take a look and possibly try it. ;)
>
> These patches apply on top of Linus's latest tree.
>
> Thanks!
>
> /ac
>
> drivers/acpi/pci_slot.c | 15 ++++++-
> drivers/pci/hotplug/acpiphp.h | 2 -
> drivers/pci/hotplug/acpiphp_core.c | 18 +++++----
> drivers/pci/hotplug/fakephp.c | 16 ++++++--
> drivers/pci/hotplug/pci_hotplug_core.c | 4 --
> drivers/pci/hotplug/pciehp.h | 6 +--
> drivers/pci/hotplug/pciehp_core.c | 7 ---
> drivers/pci/hotplug/pciehp_hpc.c | 19 ++++-----
> drivers/pci/hotplug/pcihp_skeleton.c | 12 ++++--
> drivers/pci/hotplug/shpchp.h | 5 +-
> drivers/pci/hotplug/shpchp_core.c | 29 ++++----------
> drivers/pci/slot.c | 65 +++++++++++++++++++++++++++++----
> include/linux/pci.h | 3 -
> 13 files changed, 124 insertions(+), 77 deletions(-)
>
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