Re: [Regression] [PCI/ASPM] [ASUS PN51] Reboot on resume attempt (bisect done; commit found)

[michael]

Hi Kai-Heng,

 ---- On Thu, 07 Mar 2024 07:51:05 +0100  Kai-Heng Feng  wrote --- 
 > Hi Michael,
 > 
 > Sorry for the belated response.
 > 
No worries.

 > On Wed, Jan 10, 2024 at 8:40 PM Michael Schaller michael@xxxxxxxxxxx> wrote:
 > >
 > >
 > > On 10.01.24 04:43, Kai-Heng Feng wrote:
 > > > On Fri, Jan 5, 2024 at 11:51 PM Bjorn Helgaas helgaas@kernelorg> wrote:
 > > >>
 > > >> On Fri, Jan 05, 2024 at 12:18:32PM +0100, Michael Schaller wrote:
 > > >>> On 05.01.24 04:25, Kai-Heng Feng wrote:
 > > >>>> Just wondering, does `echo 0 > /sys/power/pm_asysnc` help?
 > > >>>
 > > >>> Yes, `echo 0 | sudo tee /sys/power/pm_async` does indeed also result in a
 > > >>> working resume. I've tested this on kernel 6.6.9 (which still has commit
 > > >>> 08d0cc5f3426). I've also attached the relevant dmesg output of the
 > > >>> suspend/resume cycle in case this helps.
 > > >>
 > > >> Thanks for testing that!
 > > >>
 > > >>> Furthermore does this mean that commit 08d0cc5f3426 isn't at fault but
 > > >>> rather that we are dealing with a timing issue?
 > > >>
 > > >> PCI does have a few software timing requirements, mostly related to
 > > >> reset and power state (D0/D3cold).  ASPM has some timing parameters,
 > > >> too, but I think they're all requirements on the hardware, not on
 > > >> software.
 > > >>
 > > >> Adding an arbitrary delay anywhere shouldn't break anything, and other
 > > >> than those few required situations, it shouldn't fix anything either.
 > > >
 > > > At least it means 8d0cc5f3426 isn't the culprit?
 > > >
 > > > Michael, does the issue happen when iwlwifi module is not loaded? It
 > > > can be related to iwlwifi firmware.
 > > >
 > > > Kai-Heng
 > > >
 > > The issue still happens if the iwlwifi module has been blacklisted and
 > > after a reboot. This was again with vanilla kernel 6.6.9 and I've
 > > confirmed via dmesg that iwlwifi wasn't loaded.
 > 
 > Can you please give latest mainline kernel a try? With commit
 > f93e71aea6c60ebff8adbd8941e678302d377869 (Revert "PCI/ASPM: Remove
 > pcie_aspm_pm_state_change()") reverted.
 > 
 > Also do you have efi-pstore enabled? Is there anything logged in
 > /var/lib/systemd/pstore (assuming systemd is used)?
 > 
I'm happy to test once I'm out of the hospital (long COVID). I should be back home in 5 weeks.

Michael

 > Kai-Heng
 > 
 > >
 > > I've also checked if there is a newer firmware but Ubuntu 23.10 is
 > > already using the newest firmware available from
 > > https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/log/iwlwifi-8265-36.ucode
 > > (version 36.ca7b901d.0 according to dmesg).
 > >
 > > Michael
 > >
 > > >>
 > > >> Bjorn
 >