IJ41620: LINUX KERNEL RETBLEED FIXES BREAK MMBUILDGPL MODULE BUILD

APAR status

• Closed as program error.

Error description

• Running mmbuildgpl on x86_64 with Linux kernels that include
  fixes for the retbleed vulnerability (CVE-2022-29900) results
  in an error. As a result, GPFS is not usable with these kernel
  versions. Specifically, this problem is hit with:
  
      SLES 15 SP3 kernel update 5.3.18-150300.59.87.1 or higher
      SLES 15 SP4 kernel update 5.14.21-150400.24.11.1
      Ubuntu 22.04 kernel update 5.15.0-45.48
  
      It is expected that the same changes will also be
  backported to RHEL, but no RHEL kernel updates with retbleed
  fixes have been released yet. The same applies to
  Ubuntu 20.04; no kernel updates have been released yet
  with this changes, but this should happen eventually.
  
  The information provided by the
  Linux distributions are useful references:
      https://www.suse.com/security/cve/CVE-2022-29900.html
      https://ubuntu.com/security/CVE-2022-29900
      https://access.redhat.com/security/cve/CVE-2022-29900
  

Local fix

• The required change can also be applied manually:
  Edit the file /usr/lpp/mmfs/src/gpl-linux/Kbuild
  Around line 100 there is a line:
     $(KBHOSTPROGS) := lxtrace
  Before that line, add a new one with:
     CFLAGS_kdump-kern.o += -mfunction-return=keep
  Save the file and run mmbuildgpl again.
  

Problem summary

• Running mmbuildgpl on x86_64 with Linux kernels that include
  fixes for the retbleed vulnerability (CVE-2022-29900) results
  in an error. As a result, GPFS is not usable with these kernel
  versions. Specifically, this problem is hit with:
  
      SLES 15 SP3 kernel update 5.3.18-150300.59.87.1 or higher
      SLES 15 SP4 kernel update 5.14.21-150400.24.11.1
      Ubuntu 22.04 kernel update 5.15.0-45.48
  
      It is expected that the same changes will also be
  backported to RHEL, but no RHEL kernel updates with retbleed
  fixes have been released yet. The same applies to
  Ubuntu 20.04; no kernel updates have been released yet
  with this changes, but this should happen eventually.
  
  The information provided by the
  Linux distributions are useful references:
      https://www.suse.com/security/cve/CVE-2022-29900.html
      https://ubuntu.com/security/CVE-2022-29900
      https://access.redhat.com/security/cve/CVE-2022-29900
  

Problem conclusion

• This problem is fixed in 5.1.2 PTF 7
  To see all Spectrum Scale APARs and
  their respective fix solutions refer to page
  https://public.dhe.ibm.com/storage/spectrumscale/spectrum_scale_
  apars.html
  
  Benefits of the solution:
  Fix the mmbuildgpl compile process, so that modules can
  be compiled and GPFS can be started with these kernel updates.
  
  Work Around:
  The required change can also be applied manually:
  Edit the file /usr/lpp/mmfs/src/gpl-linux/Kbuild
  Around line 100 there is a line:
     $(KBHOSTPROGS) := lxtrace
  Before that line, add a new one with:
     CFLAGS_kdump-kern.o += -mfunction-return=keep
  Save the file and run mmbuildgpl again.
  Problem trigger:
  This problem occurs when updating the Linux kernel
  to a version with retbleed patches included.
  Symptom:
  Component Level Outage (GPFS will be unusable on the node)
  Platforms affected: x86_64-linux only
  Functional Area affected: All Scale Users
  Customer Impact: High Importance
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  SPEC SCALE STD

• Fixed component ID

  5737F33AP

Applicable component levels