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Message-ID: <5598b690-12da-4237-b2bf-c9c691c4647c@5challer.de>
Date: Tue, 2 Jan 2024 14:50:40 +0100
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Subject: Re: [Regression] [PCI/ASPM] [ASUS PN51] Reboot on resume attempt
 (bisect done; commit found)
To: Bjorn Helgaas <helgaas@kernel.org>
Cc: bhelgaas@google.com, kai.heng.feng@canonical.com,
 linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
 regressions@lists.linux.dev, macro@orcam.me.uk, ajayagarwal@google.com,
 sathyanarayanan.kuppuswamy@linux.intel.com, gregkh@linuxfoundation.org,
 hkallweit1@gmail.com, michael.a.bottini@linux.intel.com,
 johan+linaro@kernel.org
References: <20240101221554.GA1693060@bhelgaas>
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From: Michael Schaller <michael@5challer.de>
In-Reply-To: <20240101221554.GA1693060@bhelgaas>
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On 01.01.24 23:15, Bjorn Helgaas wrote:
> On Mon, Jan 01, 2024 at 07:57:40PM +0100, Michael Schaller wrote:
>> On 01.01.24 19:13, Bjorn Helgaas wrote:
>>> On Mon, Dec 25, 2023 at 07:29:02PM +0100, Michael Schaller wrote:
>>> ...
> 
>>> So unless somebody has a counter-argument, I plan to queue a revert of
>>> 08d0cc5f3426 ("PCI/ASPM: Remove pcie_aspm_pm_state_change()") for
>>> v6.7.
>>
>> If it helps I could also try if a partial revert of 08d0cc5f3426 would be
>> sufficient. This might also narrow down the issue and give more insight
>> where the issue originates from.
> 
> We're so close to the v6.7 final release that I doubt we can figure
> out the problem and test a fix before v6.7.  I'm sure Kai-Heng would
> appreciate any additional data, but I don't think it's urgent at this
> point.
> 
> Bjorn

We're indeed close to the final v6.7 release, which in turn means that a 
last minute revert of a 16 month old commit might cause even more 
regressions as there have been quite a few ASPM changes afterwards and 
there won't be much testing anymore before the final release.

Furthermore, given the age of the commit and that it has been backported 
to kernel 5.15, the question is also if the revert would be backported 
to the affected LTS kernels?

If this regression risk is acceptable then I'm all for reverting the 
commit now and then working on a fix.

Michael