Ryzen issues on FreeBSD ?

[Don Lewis]

On 17 Jan, Mike Tancsa wrote:
> On 1/17/2018 8:43 AM, Pete French wrote:
>> 
>> Are you running the latest STABLE ? There were some patches for Ryzen
>> which went in I belive, and might affect te stability. Specificly the
>> chnages to stop it locking up when executing code in the top page ?
> 
> Hi,
> 	I was testing with RELENG_11 as of 2 days ago.  The fix seems to be there
> 
> # sysctl -A hw.lower_amd64_sharedpage
> hw.lower_amd64_sharedpage: 1
> 
> Would love to find a class of motherboard that pushes its "You dont need
> to dork around with any BIOS settings. It just works.  Oh, and we have a
> hardware watchdog too".... ipmi would be stellar.

The shared page change fixed the random lockup and silent reboot problem
for me.  I've got a 1700X eight core CPU and a Gigabyte X370 Gaming 5. I
did have to RMA my CPU (it was an early one) because it had the problem
with random segfaults that seemed to be triggered by process migration
between CPU cores.  I still haven't switched over to using it for
package builds because I see more random fallout than on my older
package builder.  I'm not blaming the hardware for that at this point
because I see a lot of the same issues on my older machine, but less
frequently.

One thing to watch (though it should be less critical with a six core
CPU) is VRM cooling.  I removed the stupid plastic shroud over the VRM
sink on my motherboard so that it gets some more airflow.