[Bug 230144] Linux emulator does not work on Ryzen / Epic processors

[bugzilla-noreply at freebsd.org]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=230144

            Bug ID: 230144
           Summary: Linux emulator does not work on Ryzen / Epic
                    processors
           Product: Base System
           Version: 11.2-STABLE
          Hardware: amd64
                OS: Any
            Status: New
          Severity: Affects Some People
          Priority: ---
         Component: kern
          Assignee: bugs at FreeBSD.org
          Reporter: pete at twisted.org.uk

Trying to run any Linux binary on Ryzen or Epic coredumps. I trying to
backtrace the core but the debugger does not seem to be able to get any
information ut of the binary.

This is completely AMD Zen specific - I can take the same disc and boot it up
with a Xeon processor and it works fine. I have also used the Linux emulator on
older AMD processors fine (my desktop was a Phenom II until I upgraded it to
the Ryzen) but I have to admit I haven't been able to try the latest kernel on
older AMD processors.

Reproducing is trivial - enable Linux in rc.conf, install linux_base-c7 and try
and run /compat/linux/bin/bash. It will immediately coredump on a Zen machine,
but plugging the same disc into an Intel machine will run it fine.

-- 
You are receiving this mail because:
You are the assignee for the bug.