Hi Salvatore,
meanwhile, Dell has replaced the mainboard of my laptop, and after that,
both the USB over-current kernel messages and the kworker processes with
high CPU load are gone.
Many thanks for caring about my bug report!
Best regards,
Dirk.
Am 29.08.20 um 11:26 schrieb Salvatore Bonaccorso:
Hi Dirk,
Thanks for testing that.
On Sat, Aug 29, 2020 at 11:04:43AM +0200, Dirk Kostrewa wrote:
Hi Salvatore,
I have enabled the verbose debugging mode on the command line and have
appended the first 5000 lines of the dmesg output to this e-mail, running
the current kernel from the Buster backports with the two kworker processes
with high CPU load present.
After that, I have applied your patch to this kernel and rebooted with the
patched kernel:
5.7.0-0.bpo.2-amd64 #1 SMP Debian 5.7.10-1~bpo10+1a~test (2020-08-28) x86_64
GNU/Linux
With your patch applied, the two kworker processes with high CPU load
completely disappeared!
Unfortunately I suspect this indicates either a HW fault or a HW
design error as stated in the found kernel-thread which was just
uncovered by the mentioned kernel fix (which we temporarily reverted
with the patch). I can try to ask Alan Stern.
There might be a workaround workarble for you, the issue should
disapear if you prevent the system to automatically try to suspend
usb2 root hub (but you have the same on usb1 root hub).
# echo on >/sys/bus/usb/devices/usb2/power/control
will do that for the usb2 root hub.
Regards,
Salvatore
