Ryzen issues on FreeBSD ? (with sort of workaround)

[Don Lewis]

On 20 Apr, Pete French wrote:
> So, resurrecting the thread from a few weeks ago, as I finally found
> time yesterday to out together the Ryzen machine I bought the parts for in
> Jaunary (busy year at work....). All went smoothl;y, checked it
> booted up, used it for 15 minutes, was impressed by the speed and went home.
> 
> ...and by the time I got home, an hour or so later, it had locked up hard.
> 
> I was somewhat dissapointed, as I had seen various fixes go in,. and had hoped
> the issues were fixed. This morning I have booted the machine back up,
> tweaking the BIOPS to do things mentioned in this thread, viz:
> 
> 	Disable Turbo Boost
> 	Disable SMT
> 	Disable global C-states
> 
> The memory was already ruunning correctly at 2133 (though I have locked that
> in the BIOS too) and I was already using kern.eventtimer.periodic=1, so
> the lockup was not related to those. Its the latest BIOS, and a -STABLE
> build from yesterday.
> 
> I suspect it will now be stable, but I was wondering if anyone was any further
> forward on working out which of the settings above are the ones which 'fix'
> the issue - or indeed if its really fixed, by them or just made far less likely
> to happen.
> 
> Anyone got any more comments on this ?

In terms of hangs and system crashes, my Ryzen system has been stable
since the fix to relocate the shared page.

The random segfault problem during parallel builds went away when I
RMAed my original, early-build CPU.

This commit:
  r329254 | kib | 2018-02-13 16:31:45 -0800 (Tue, 13 Feb 2018) | 43 lines

  Ensure memory consistency on COW.

Fixed most of the remaining random port build errors that I had.  I
think the only remaining problem is random build failures of
guile-related ports, but I also see these on my FX-8320E, so they are
not Ryzen-specific.

Pretty much all of my BIOS settings are the defaults.

I suspect that the idle hang issues are motherboard and/or BIOS
specific.  For the record my motherboard is a Gigabyte
GA-AX370-Gaming 5.