Bug ID 933809: Too many interrupts from console serial port starve TMM for CPU time

Last Modified: Apr 29, 2023

Affected Product(s):
BIG-IP APM, LTM(all modules)

Known Affected Versions:
14.1.0,,,,,, 14.1.2,,,,,,,,, 14.1.3,, 14.1.4,,,,,,, 14.1.5,,,,, 15.1.0,,,,,, 15.1.1, 15.1.2,, 15.1.3,, 15.1.4,, 15.1.5,, 15.1.6,, 15.1.7, 15.1.8,,, 16.1.0, 16.1.1, 16.1.2,,, 16.1.3,,,,, 17.0.0,,

Opened: Aug 05, 2020

Severity: 4-Minor


TMM crashes and the following error is found in the kernel log file: "err kernel: serial8250: too much work for irq4"


Traffic is disrupted while TMM restarts.


Occurs due to performing heavy I/O over the serial console. For example, running tcpdump and dumping the output to the console while the device is under heavy load.



Fix Information


Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips