Reading of /proc/timer_list file leads to NMI watchdog soft lockups.

Solution In Progress - Updated -


  • System reports soft lockups when :
    • Accessing /proc/timer_list file either once or repeatedly from shell or shell script or periodically from some monitoring
      software that reads this file and stores data from it.
    • Executing sosreport command where plug-in kernel.with-timer reads data from /proc/timer_list file.
    • Large number of user space applications that does a lot of timer-based activities. For example, doing 1000+ of nanosleep() calls or very high network activity when a lot of network-related timers are registered in the kernel.


  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 6

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