On Thu, Feb 06, 2025 at 11:00:18AM +0200, Ilpo Järvinen wrote:
> On Wed, 5 Feb 2025, Greg Kroah-Hartman wrote:
>
> > 6.13-stable review patch. If anyone has any objections, please let me know.
> >
> > ------------------
> >
> > From: Jian-Hong Pan <jhp@xxxxxxxxxxxxx>
> >
> > [ Upstream commit 1db806ec06b7c6e08e8af57088da067963ddf117 ]
> >
> > After 17423360a27a ("PCI/ASPM: Save L1 PM Substates Capability for
> > suspend/resume"), pci_save_aspm_l1ss_state(dev) saves the L1SS state for
> > "dev", and pci_restore_aspm_l1ss_state(dev) restores the state for both
> > "dev" and its parent.
> >
> > The problem is that unless pci_save_state() has been used in some other
> > path and has already saved the parent L1SS state, we will restore junk to
> > the parent, which means the L1 Substates likely won't work correctly.
> >
> > Save the L1SS config for both the device and its parent in
> > pci_save_aspm_l1ss_state(). When restoring, we need both because L1SS must
> > be enabled at the parent (the Downstream Port) before being enabled at the
> > child (the Upstream Port).
> >
> > Link: https://lore.kernel.org/r/20241115072200.37509-3-jhp@xxxxxxxxxxxxx
> > Fixes: 17423360a27a ("PCI/ASPM: Save L1 PM Substates Capability for suspend/resume")
> > Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218394
> > Suggested-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
> > Signed-off-by: Jian-Hong Pan <jhp@xxxxxxxxxxxxx>
> > [bhelgaas: parallel save/restore structure, simplify commit log, patch at
> > https://lore.kernel.org/r/20241212230340.GA3267194@bhelgaas]
> > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> > Tested-by: Jian-Hong Pan <jhp@xxxxxxxxxxxxx> # Asus B1400CEAE
> > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
>
> Hi stable maintainers,
>
> Please withhold this commit from stable until its fix ("PCI/ASPM: Fix L1SS
> saving") can be pushed at the same as having this commit alone can causes
> PCIe devices to becomes unavailable and hang the system during PM
> transitions.
>
> The fix is currently in pci/for-linus as the commit c312f005dedc, but
> Bjorn might add more reported-by/tested-by tags if more people hit it
> before the commit makes into Linus' tree so don't expect that commit id to
> be stable just yet.
Ok, now dropped from all stable queues, thanks for letting us know.
greg k-h
