On 10.01.24 04:43, Kai-Heng Feng wrote:
On Fri, Jan 5, 2024 at 11:51 PM Bjorn Helgaas <helgaas@xxxxxxxxxx> 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.
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
