Comme=
nt # 36
on bug 10667=
1
from Alan W. Irwin
(In reply to fin4478 from comment #35)
> To prevent random kernel lock ups with Ryzen, en=
able RCU_NOCB_CPU in the
> kernel configuration and boot the kernel with the rcu_nocbs=3D0-X com=
mand
> line parameter. X is the cpu thread count -1. To fix this with bios, s=
et to
> Typical Current Idle in the bios Advanced/AMD CBS menu.
I was quickly able to verify all you said at
<https://community.a=
md.com/thread/225795> and
<https:=
//bugzilla.kernel.org/show_bug.cgi?id=3D196683>. So it appears all =
Linux
Ryzen owners should be aware of this "idle" issue and take the ne=
cessary
workarounds, but despite over many months publicizing my Linux Ryzen troubl=
es
in a number of different Linux forums (including this bug report) and many
different google searches I remained clueless about this bad Linux Ryzen
situation until now. So many thanks for being the first to clue me in!
It took me a while to figure out how to rebuild the latest Debian Buster ke=
rnel
(4.18.10) with RCU_NOCB_CPU enabled, but I have done that now and just rebo=
oted
with that custom kernel using the rcu_nocbs=3D0-15 kernel parameter (my Ryz=
en 7
1700 has 8 cores and 16 threads).
So my hopes are high that this step will clean up the lockup issues I have =
been
experiencing when my system was idling at night. But I have also experienc=
ed
lockups when the system was being used so the rcu_nocbs=3D0-15 workaround m=
ay not
be the sole step I have to take to stabilize my Linux Ryzen system.