================ /proc/sys/debug/

These files show up in /proc/sys/debug/, depending on the kernel configuration:

.. contents:: :local:

exception-trace

This flag controls whether the kernel prints information about unhandled signals (like segmentation faults) to the kernel log (dmesg).

• 0: Unhandled signals are not traced.
• 1: Information about unhandled signals is printed.

The default value is 1 on most architectures (like x86, MIPS, RISC-V), but it is 0 on arm64.

The actual information printed and the context provided varies significantly depending on the CPU architecture. For example:

• On x86, it typically prints the instruction pointer (IP), error code, and address that caused a page fault.
• On PowerPC, it may print the next instruction pointer (NIP), link register (LR), and other relevant registers.

When enabled, this feature is often rate-limited to prevent the kernel log from being flooded during a crash loop.

kprobes-optimization

This flag enables or disables the optimization of Kprobes on certain architectures (like x86).

• 0: Kprobes optimization is turned off.
• 1: Kprobes optimization is turned on (default).

For more details on Kprobes and its optimization, please refer to Documentation/trace/kprobes.rst.

Copyright (c) 2026, Shubham Chakraborty [email protected]

For general info and legal blurb, please look in Documentation/admin-guide/sysctl/index.rst.

.. See scripts/check-sysctl-docs to keep this up to date: .. scripts/check-sysctl-docs -vtable="debug"
.. $(git grep -l register_sysctl_)