[Pkg-zfsonlinux-devel] Bug#940932: zfs-dkms: Reads from ZFS volumes cause system instability when SIMD acceleration is enabled.

[Alexander]

A quick update:

I have booted up the Debian live USB on another machine and was able to 
reproduce this bug with it.

The machine had the Ryzen 5 2600 CPU (the one I swapped with the machine 
I have originally found the problem on).

The Mainboard is: ASUS PRIME B350-PLUS
BIOS Version: 5216

Output of uname -a:
Linux debian 4.19.0-6-amd64 #1 SMP Debian 4.19.67-2 (2019-08-28) x86_64 
GNU/Linux

Output of zfs --version:
zfs-0.8.1-4~bpo10+1
zfs-kmod-0.8.1-4~bpo10+1

Also here are the steps I'm taking to reproduce the problem:

- Start mprime for linux 64 bit
- Select Torture Test
- Choose 12 torture test threads in case of ryzen 5 (default setting)
- Select Test (2) Small FFT
- All other settings are set to default settings
- Run the test
- Read data from zfs by either reading a large file or starting a scrub. 
(raidz scrubs are escpecially effective)

Within a few seconds you should see mprime reporting errors.