Re: 4.9-rc1: [TMP_] ACPI namespace lookup failure, AE_ALREADY_EXISTS

["Rafael J. Wysocki" <rafael@kernel.org>]

On Thu, Oct 20, 2016 at 8:44 PM, Zheng, Lv <lv.zheng@intel.com> wrote:
> Hi,
>
>> From: Deak, Imre
>> Subject: 4.9-rc1: [TMP_] ACPI namespace lookup failure, AE_ALREADY_EXISTS
>>
>> Hi,
>>
>> after upgrading to 4.9-rc1 I get the following errors occasionally
>> during boot and suspend-to-ram on an APL system:
>>
>> [   59.513434] ACPI Error: [TMP_] Namespace lookup failure, AE_ALREADY_EXISTS (20160831/dswload2-330)
>> [   59.513446] ACPI Exception: AE_ALREADY_EXISTS, During name lookup/catalog (20160831/psobject-227)
>> [   59.513469] ACPI Error: Method parse/execution failed [\_SB.PCI0.SCPG] (Node ffff8802770b7bb8),
>> AE_ALREADY_EXISTS (20160831/psparse-543)
>> [   59.515415] ACPI Error: Method parse/execution failed [\_SB.PCI0.SDHA._PS3] (Node ffff8802770b7dc0),
>> AE_ALREADY_EXISTS (20160831/psparse-543)
>> [   59.517118] ACPI: Marking method _PS3 as Serialized because of AE_ALREADY_EXISTS error
>>
>> Other than these error messages, booting and suspend/resume seems to work ok.
>> Bisecting points to
>> commit 74f51b80a0c4ff84fbeb7f12ea43ce66934d29aa
>> Author: Lv Zheng <lv.zheng@intel.com>
>> Date:   Wed Sep 7 14:07:10 2016 +0800
>>
>>     ACPICA: Namespace: Fix dynamic table loading issues
>>
>> Reverting this on top of 4.9-rc1 gets rid of the error messages.
>
> The commit in question only modified code to make locks unlocked/locked.
> Which should be transparent to the functional stuffs.

It might change the relative timing of thigs (which might result in
ordering changes).

> I'm not sure how it can lead to such error in the single-threading boot environment.

Why do you think it's single-threaded?  At least suspend/resume isn't
in general.

Thanks,
Rafael