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 id 1fj0Uf-0005MX-4I; Fri, 27 Jul 2018 11:01:09 +0000
Subject: Re: Ryzen issues on FreeBSD ? (with sort of workaround)
To: Konstantin Belousov <kostikbel@gmail.com>
Cc: avg@freebsd.org, eric@vangyzen.net, freebsd-stable@freebsd.org,
 freebsd@hda3.com, truckman@FreeBSD.org
References: <20180705133542.GG5562@kib.kiev.ua>
 <E1fb4mD-0006j7-SY@dilbert.ingresso.co.uk>
 <20180705145130.GH5562@kib.kiev.ua>
From: Pete French <petefrench@ingresso.co.uk>
Message-ID: <548b493e-6a51-32ca-b3c1-216cac037e8b@ingresso.co.uk>
Date: Fri, 27 Jul 2018 12:01:09 +0100
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So, I have been running the patched kernel for quiet a while now, and it 
works fine for me, but last night I did hit a surprising issue - the 
Linux emulator does not work on Ryzen / Epyc. I tried this on two 
machines (both with the patches) and it coredumps when simply running 
bash on both of them. I copied the OS over to an Intel machine, and that 
works fine.

I have not tried running with an unpatched kernel on the Ryzen machine 
(I dont have one to hand) but I did try applying the sysctls to the 
Intel box to see if that wuld cause the Linux binaries to crash. It didn't.

-pete.