Re: [PATCH v8 1/4] PCI: host-common: Fix early bus-walk exit in d3cold_possible()

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [Low] PCI: host-common: missing Fixes trailer for
  __pci_host_common_d3cold_possible()
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commit 846cf26aeb81e6f1edca4dcbd23133cd3972fd62
Author: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>

> PCI: host-common: Fix early bus-walk exit in d3cold_possible()
>
> __pci_host_common_d3cold_possible() returns -EOPNOTSUPP for the first
> downstream device it finds outside PCI_D3hot, and pci_walk_bus() aborts
> the walk as soon as its callback returns nonzero. Any device enumerated
> after the disqualifying one -- including a wakeup-enabled, PME-from-D3cold
> capable endpoint -- is then never visited, so pme_capable can come back
> false even though such a device exists on the bus.
>
> Since pci_host_common_d3cold_possible() already returns false whenever
> any device disqualifies D3cold, aborting the walk buys nothing for the
> plain suspend path: the overall bool result is unaffected. But it
> silently drops pme_capable detection for any device ordered after the
> disqualifying one.
>
> This matters for the upcoming shutdown path in particular: unlike plain
> suspend, shutdown forces the link into L2/D3cold regardless of whether
> pci_host_common_d3cold_possible() itself allows it (see the following
> "force_d3cold" changes), so at shutdown time it's common for an
> endpoint to still be in D0 and disqualify D3cold while a later,
> PME-capable device is never visited. dw_pcie_suspend_noirq() still
> uses "pme_capable" to set pci->pp.skip_pwrctrl_off, so an inaccurate
> result here can cause Vaux/wakeup support to be dropped for a device
> that actually supports PME from D3cold.
>
> Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>

[Severity: Low]
This fixes the early-exit bug in __pci_host_common_d3cold_possible().
Should this include:

  Fixes: 1d2a29ccd3a1 ("PCI: host-common: Add pci_host_common_d3cold_possible() helper")

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Sashiko AI review · https://sashiko.dev/#/patchset/20261107-shutdown-v8-0-bf607c6429b0@oss.qualcomm.com?part=1