BUG: kernel NULL pointer dereference and BUG: workqueue lookups at sleep and hibernate with LRNG. #27
Description
As a suggestion by @pfactum, the maintainer of the -pf Linux kernel (patchset), I report here that I had issues at sleep and hibernation with the LRNG patchset.
Affected kernels
I had it with
- Linux 6.1-pf2 and
- Linux 6.1-pf5 (I did not try the intermediates), and
- it was gone with Linux 6.1-pf6, where LRNG was dropped, and
- I did not had it with 6.0-pf5.
I had it with
- self-compiled pf-kernels where I had many LRNG options enabled, but
- not with pre-compiled pf-kernel where far less LRNG options were set.
- I also did not have it with self-compiled vanilla kernel which does not have LRNG.
Problem description
I got
BUG: kernel NULL pointer dereference, address: 0000000000000088
and then subsequent
BUG: workqueue lockup - pool cpus=3 node=0 flags=0x0 nice=0 stuck for [number]s!
at suspend-to-disk and at sleep.
When doing suspend-to-disk, the machine did not power off and showed the kernel errors. However, when I forced power-off, I could resume, and got an unstable working environment (programmes started to stall or not to execute at all) spitting out dmesg logs.
When doing sleep, I had to force power off to get the machine usable again.
Attached error logs
I attach two dmesg logs I could capture after resume (the first log was captured after longer time use, then suspend, then resume, and then having it sit and tried to beeing used for some time; the second log after suspend shortly after bootup and not so much usage time after resume):
dmesg_after_errorneous_hibernation_forced_off_and_resume.01.log,dmesg_after_errorneous_hibernation_forced_off_and_resume.02.log.
Attached kernel configs
I attach:
- The kernel
.configs of- Vanilla linux kernel 6.1.12 from kernel.org:
kernel-config.6.1.12-vanilla-custom.kconf.txt, - Precompiled linux-pf-silvermont 6.1-pf5:
kernel-config.6.1.0-pf5-precompiled.kconf.txt, - custom compiled linux-pf 6.0-pf4:
kernel-config.6.0.0-pf5-custom.kconf.txt, - custom compiled linux-pf 6.1-pf5:
kernel-config.6.1.0-pf5-custom.kconf.txt.
- Vanilla linux kernel 6.1.12 from kernel.org:
kconfig-diffof- kernel config i. and iv.:
kconfig-diff_-_6.1.12-vanilla-custom_-_6.1.0-pf5-custom.kconf.txt, - kernel config ii. and iv.:
kconfig-diff_-_6.1.0-pf5-precompiled_-_6.1.0-pf5-custom.kconf.txt, - kernel config iii. and iv.:
kconfig-diff_-_6.0.0-pf5-custom_-_6.1.0-pf5-custom.kconf.txt.
- kernel config i. and iv.:
(Note that kernels i., ii. and iii. did not show the problem, but iv. does.)
Notes.
I have not the capacity to assist debugging (recompiling kernel needs a lot of time; and for my productivity I heavily rely on suspend-to-disk, so each time I reboot to another kernel I have a considerable productivity impact).
I am already running a kernel not anymore affected by this.
I report this here in the hope that it might help you nevertheless.