[Bi-users] Intel microcode updates reverted

[Kent Engström]

Dear Bi Users,

we have today decided to revert the Intel microcode update that is part
of the "Spectre variant 2" mitigation used by RHEL/CentOS 6.

We are doing this using a rolling node upgrade. Jobs that have started
14:22 today or later are running on the new nodes with reverted microcode.

The main reason for doing this is that Intel has withdrawn the microcode
while they are working on a bug-fixed version. Also, we have received
error reports and also seen some node crashes, that could be related to
this, so we now believe that staying on the latest microcode while we
wait for the update is worse than doing the revert to an older version.

Here's the caveat: when Intel releases fixed microcode, we will want to
update to that. How fast we do that will probably depend on the threat
situation (for example, if working exploits using Spectre variant 2 are
available). If possible, we would like to setup a reservation, where
nodes running the new microcode can be tested by interested users before
the main upgrade.

If you are one of the users who have contacted us about code working
before 5/1 and not after (therefore suspecting it to be
mitigation-related), please check again now and get back to us with
status udpates.




-- 
Kent Engström, National Supercomputer Centre
kent at nsc.liu.se, +46 13 28 4444