[Discuss] Issues with new Linux computer mostly addressed

[Alan W. Irwin]

To follow up on this old thread, my half-year-old AMD Ryzen 7 1700
computer is *still* unstable with uptimes which range from 1 day to ~3
weeks until the inevitable kernel lockup occurs.

Each lockup seems to have slightly different symptoms.  For example,
some are accompanied by no log messages, and others are accompanied by
large numbers of NMI messages (with some mentioning the e1000e kernel
module that drives my Intel LAN card, but most NMI messages not doing
that).  So all this bad 6 months I have been reporting these issues
and pursuing various faint clues with no help at all from google
searches since the number of irrelevant hits for the <ryzen lockup>
search terms are so large. But for one of my bug reports a kind
responder said the following this morning:

To prevent random kernel lock ups with Ryzen, enable RCU_NOCB_CPU in
the kernel configuration and boot the kernel with the rcu_nocbs=0-X
command line parameter. X is the cpu thread count -1 [which would be
15 for my Ryzen 7 1700]. To fix this with bios, set to Typical Current
Idle in the bios Advanced/AMD CBS menu.

Using this comment to refine my google search terms I quickly found
<https://community.amd.com/thread/225795> and
<https://bugzilla.kernel.org/show_bug.cgi?id=196683> which confirmed
that my Ryzen linux lockup problems are common, but could be
addressed by the two methods (kernel parameter or BIOS option) he discussed
with some users finding that only the latter option worked, but they typically
needed the absolutely latest BIOS update to get access to that option.

So as a result I plan to rebuild my Debian kernel with CONFIG_RCU_NOCB_CPU=y and set
the kernel parameter rcu_nocbs=0-15 (15 is appropriate for Ryzen 7 1700)
for that custom kernel.  And I hope that will finally solve these lockups, but
if not I will probably need to do a BIOS update which will be the topic
my next post.

Alan
__________________________
Alan W. Irwin

Programming affiliations with the FreeEOS equation-of-state
implementation for stellar interiors (freeeos.sf.net); the Time
Ephemerides project (timeephem.sf.net); PLplot scientific plotting
software package (plplot.sf.net); the libLASi project
(unifont.org/lasi); the Loads of Linux Links project (loll.sf.net);
and the Linux Brochure Project (lbproject.sf.net).
__________________________

Linux-powered Science
__________________________