Hello,
My apologies if you are receiving a duplicate of this message. I
attempted to email this earlier but was sent a delivery failure status
reply due to html content. I will attempt to resend it as plain text.
Original Email:
The 2019-01-26 commit to the asus-wmi.c driver code in the 4.4 kernel
branch has introduced a bug with several known models of EeePC netbooks.
Description of Problem:
The bug occurs during boot, where the screen (possibly backlight?) will
shut off and display hotkeys are unable to bring it back on. The problem
is present on all kernels
since the 2019-01-26 commit. There have been several reports of the
issue in the slackware forum at linuxquestions.org
Corrective actions taken so far:
Appending acpi_osi=Linux will circumvent the issue and keep the screen
on, but this causes several error messages
in the boot log about eeepc_wmi "failing to load both WMI and and legacy
ATKD devices", and warns not to use acpi_osi=Linux.
Appending acpi_backlight=vendor also prevents the screen from shutting
off during boot. However, pressing the brightness hotkeys
causes the system to hang.
Reversing the asus-wmi.c patch that was committed on 2019-01-26 and
rebuilding the 4.4 series module also fixes the problem, and brightness
hotkeys work normally. The commit in question is
0c4a25cc6f2934f3aa99a0bbfd20b71949bcad25
Model I have tested this on: ASUS EeePC 1000H (Slackware 14.2, kernels
4.4.201, 4.4.202)
Additional models reporting this issue: ASUS Eee PC 1005HAB, ASUS Eee PC
1225b, ASUS Eee PC 1025c (Slackware 14.2, various kernels from 4.4.172
and higher)
Additional Notes:
This problem seems to have been corrected in the 4.19 kernel branch, as
reported by several users in the slackware forum.
I attempted to test some of the fixes from the 4.19 code as patches to
the 4.4 code but had no success. There have been multiple
changes in that branch and I am unsure what exactly has corrected the
bug in that version.
If there is any additional information that I can provide, please let me
know.
Regards,
Bob Funk
