IJ33392: GPFS DAEMON ASSERTS ON PROCESSOR WITH 5 LEVEL PAGE TABLES: "LOGASSERTFAILED: (UINTPTR)(VMALLOCSTART)"

APAR status

• Closed as program error.

Error description

• With the introduction of the 5-level
  page tables, supported by Intel's
  Ice Lake processor generation, user space memory gets expanded
  by a factor of 512. This resulted in the change of kernel base
  address and due to this GPFS asserts with message
  "logAssertFailed: (UIntPtr)(vmallocStart)"
  while validating kernel addresses.
  

Local fix

• Disable 5-level page table setting
  by adding no5lvl to the kernel
  command line and then rebooting the node. Check the
  documentation of the Linux distribution used for details on
  how to apply this change.
  For example, on RHEL8:
  # grubby --update-kernel=ALL --args="no5lvl"
  # cat /proc/cmdline
  BOOT_IMAGE=(hd0,msdos1)/vmlinuz-4.18.0-240.10.1.el8_3.x86_64
  root=/dev/mapper/rhel-root ro crashkernel=auto
  resume=/dev/mapper/rhel-swap rd.lvm.lv=rhel/root rd.lvm.lv=
  rhel/swap rhgb quiet net.ifnames=0 biosdevname=0 no5lvl
  

Problem summary

• With the introduction of the 5-level
  page tables, supported by Intel's
  Ice Lake processor generation, user space memory gets expanded
  by a factor of 512. This resulted in the change of kernel base
  address and due to this GPFS asserts with message
  "logAssertFailed: (UIntPtr)(vmallocStart)"
  while validating kernel addresses.
  

Problem conclusion

• This problem is fixed in 5.0.5  PTF 9
  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:
  
  
  No more assert
  
  Work Around:
  
  Disable 5-level page table setting
  by adding no5lvl to the kernel
  command line and then rebooting the node. Check the
  documentation of the Linux distribution used for details on
  how to apply this change.
  For example, on RHEL8:
  # grubby --update-kernel=ALL --args="no5lvl"
  # cat /proc/cmdline
  BOOT_IMAGE=(hd0,msdos1)/vmlinuz-4.18.0-240.10.1.el8_3.x86_64
  root=/dev/mapper/rhel-root ro crashkernel=auto
  resume=/dev/mapper/rhel-swap rd.lvm.lv=rhel/root rd.lvm.lv=
  rhel/swap rhgb quiet net.ifnames=0 biosdevname=0 no5lvl
  
  Problem trigger:
  
  Systems that attempt to install Spectrum Scale on a newer Intel
  x86_64 processor with 5-level page.
  
  Symptom: Assert
  
  Platforms affected: Linux x86_64 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