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Bug 1774322

Summary: [RHEL 8] Do not update SKL-SP/W/X (CPUID 0x50654, 06-55-04) to revision 0x2000065 by default
Product: Red Hat Enterprise Linux 8 Reporter: Eugene Syromiatnikov <esyr>
Component: microcode_ctlAssignee: Eugene Syromiatnikov <esyr>
Status: CLOSED ERRATA QA Contact: Jeff Bastian <jbastian>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 8.2CC: efuller, laurent.rineau__fedora, skozina
Target Milestone: rcFlags: pm-rhel: mirror+
Target Release: 8.0   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: microcode_ctl-20191115-2.el8 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of:
: 1774329 (view as bug list) Environment:
Last Closed: 2020-04-28 16:06:21 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 1710951, 1774329, 1774635    

Description Eugene Syromiatnikov 2019-11-20 02:45:55 UTC 
There are reports of issues following update to revision 0x2000065 of 06-55-04 microcode:

https://github.com/intel/Intel-Linux-Processor-Microcode-Data-Files/issues/21

Since, per [1], this revision is not required for recently unembargoed Intel CPU vulnerabilities and errata, it may be wise to disable update to it by default, the same way it has been done for SNB-EP (06-2d-07) microcode revision 0x718.

[1] https://www.intel.com/content/dam/www/public/us/en/documents/corporate-information/SA00270-microcode-update-guidance.pdf
Comment 4 Jeff Bastian 2020-03-04 17:57:39 UTC 
Verified with microcode_ctl-20191115-4.el8

Reinstalling the rpm leaves a note in the dmesg logs, and the microcode update is restricted to the previous version 0x2000064.  The "force" file to override the blacklist still works.


[root@lenovo-sr650-01 ~]# yum -y reinstall microcode_ctl-20191115-4.el8
...

[root@lenovo-sr650-01 ~]# dmesg
[ 3839.859747] Microcode revision 0x2000065 for Intel Skylake-SP/X/W (family 6, model 85,
               stepping 4; CPUID 0x50654) CPUs that has been included into microcode-20191112
               release is disabled as it may cause system instability and the previous revision
               0x2000064 is used instead.
               Please refer to /usr/share/doc/microcode_ctl/caveats/06-55-04_readme
               and /usr/share/doc/microcode_ctl/README.caveats for details.

[root@lenovo-sr650-01 ~]# journalctl -b0 --no-hostname -o short-monotonic | grep -i microcode.update
[    0.000000] kernel: microcode: microcode updated early to revision 0x2000064, date = 2019-07-31
[    7.517347] kernel: microcode: Microcode Update Driver: v2.2.
[   15.481153] systemd[1]: Starting Load CPU microcode update...
[   15.574369] systemd[1]: Started Load CPU microcode update.

[root@lenovo-sr650-01 ~]# cat /sys/devices/system/cpu/cpu0/microcode/version
0x2000064


### Force the microcode update ###

[root@lenovo-sr650-01 ~]# install -D /dev/null /etc/microcode_ctl/ucode_with_caveats/force-intel-06-55-04

[root@lenovo-sr650-01 ~]# /usr/libexec/microcode_ctl/update_ucode

[root@lenovo-sr650-01 ~]# dracut --verbose --force --early-microcode

[root@lenovo-sr650-01 ~]# lsinitrd /boot/initramfs-4.18.0-184.el8.x86_64.img | head
Image: /boot/initramfs-4.18.0-184.el8.x86_64.img: 27M
========================================================================
Early CPIO image
========================================================================
drwxr-xr-x   3 root     root            0 Feb 11 10:30 .
-rw-r--r--   1 root     root            2 Feb 11 10:30 early_cpio
drwxr-xr-x   3 root     root            0 Feb 11 10:30 kernel
drwxr-xr-x   3 root     root            0 Feb 11 10:30 kernel/x86
drwxr-xr-x   2 root     root            0 Feb 11 10:30 kernel/x86/microcode
-rw-r--r--   1 root     root        34816 Feb 11 10:30 kernel/x86/microcode/GenuineIntel.bin

[root@lenovo-sr650-01 ~]# reboot
...

[root@lenovo-sr650-01 ~]# journalctl -b0 --no-hostname -o short-monotonic | grep -i microcode.update
[    0.000000] kernel: microcode: microcode updated early to revision 0x2000065, date = 2019-09-05
[    7.540957] kernel: microcode: Microcode Update Driver: v2.2.
[   15.848569] systemd[1]: Starting Load CPU microcode update...
[   15.962939] systemd[1]: Started Load CPU microcode update.

[root@lenovo-sr650-01 ~]# cat /sys/devices/system/cpu/cpu0/microcode/version
0x2000065
Comment 6 errata-xmlrpc 2020-04-28 16:06:21 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHEA-2020:1761