Re: [PATCH] PCI/PM: Skip the suspend_noirq config save if runtime-suspended

[sashiko-bot@kernel.org]

> pci_pm_suspend_noirq() saves config space unconditionally when the driver
> of the device has no PM callbacks, which includes unbound devices.  If
> such a device is runtime-suspended, the bridge above it may be in a
> low-power state with the link down.  Depending on the platform, the
> config reads then either hang the CPU or return all ones, which overwrite
> the snapshot taken at runtime suspend and are written back to the device
> on resume.
> 
> Skip the save if the device is runtime-suspended, as pci_pm_freeze()
> does, since pci_pm_runtime_suspend() has already saved the config space.
> Use pm_runtime_status_suspended(), because runtime PM is disabled by the
> noirq phase and pm_runtime_suspended() would always be false.
> 
> Fixes: 931ff68a5a53 ("PCI PM: Restore config spaces of all devices during early resume")
> Cc: stable@vger.kernel.org # v6.19+
> Signed-off-by: Navon John Lukose <navonjohnlukose@gmail.com>

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

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Sashiko AI review · https://sashiko.dev/#/patchset/20260923022511.24932-1-navonjohnlukose@gmail.com?part=1