Re: [PATCH v4] PCI: Disable ASPM L0s for Realtek RTS525A

[sashiko-bot@kernel.org]

> The Realtek RTS525A PCIe card reader reports an AER Correctable Replay
> Timer Timeout storm when ASPM L0s is enabled on its link.  On an affected
> HP ZBook Power 16 inch G11, the Root Port received tens of millions of
> AER interrupts from the RTS525A even when the rtsx_pci driver was
> blacklisted and the endpoint was not enabled by a driver.
> 
> For example:
> 
>   pcieport 0000:00:1c.6: AER: Multiple Correctable error message received from 0000:58:00.0
>   rtsx_pci 0000:58:00.0: PCIe Bus Error: severity=Correctable, type=Data Link Layer, (Transmitter ID)
>   rtsx_pci 0000:58:00.0:   device [10ec:525a] error status/mask=00001000/00006000
>   rtsx_pci 0000:58:00.0:    [12] Timeout
>   pcieport 0000:00:1c.6: AER: Correctable error message received from 0000:58:00.0
> 
> Testing with OS-native AER control showed that disabling only L0s on the
> RTS525A link stops new AER interrupt and counter growth while leaving L1
> enabled.  Disabling L1, L1 substates, or Clock PM alone did not stop the
> storm.
> 
> Prevent the broken L0s configuration by removing L0s from the RTS525A
> advertised ASPM capability.  This avoids enabling the non-working ASPM
> state instead of masking the resulting AER Replay Timer Timeout reports.
> 
> Reviewed-by: Lukas Wunner <lukas@wunner.de>
> Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
> Cc: stable@vger.kernel.org
> Signed-off-by: Max Lee <max.lee@canonical.com>

Sashiko has reviewed this patch and found no issues. It looks great!

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Sashiko AI review · https://sashiko.dev/#/patchset/20260707021527.639611-1-max.lee@canonical.com?part=1