xref: /linux/Documentation/admin-guide/sysctl/debug.rst (revision 5181afcdf99527dd92a88f80fc4d0d8013e1b510)
1================
2/proc/sys/debug/
3================
4
5These files show up in ``/proc/sys/debug/``, depending on the
6kernel configuration:
7
8.. contents:: :local:
9
10exception-trace
11===============
12
13This flag controls whether the kernel prints information about unhandled
14signals (like segmentation faults) to the kernel log (``dmesg``).
15
16- ``0``: Unhandled signals are not traced.
17- ``1``: Information about unhandled signals is printed.
18
19The default value is ``1`` on most architectures (like x86, MIPS, RISC-V),
20but it is ``0`` on **arm64**.
21
22The actual information printed and the context provided varies
23significantly depending on the CPU architecture. For example:
24
25- On **x86**, it typically prints the instruction pointer (IP), error
26  code, and address that caused a page fault.
27- On **PowerPC**, it may print the next instruction pointer (NIP),
28  link register (LR), and other relevant registers.
29
30When enabled, this feature is often rate-limited to prevent the kernel
31log from being flooded during a crash loop.
32
33kprobes-optimization
34====================
35
36This flag enables or disables the optimization of Kprobes on certain
37architectures (like x86).
38
39- ``0``: Kprobes optimization is turned off.
40- ``1``: Kprobes optimization is turned on (default).
41
42For more details on Kprobes and its optimization, please refer to
43Documentation/trace/kprobes.rst.
44
45Copyright (c) 2026, Shubham Chakraborty <chakrabortyshubham66@gmail.com>
46
47For general info and legal blurb, please look in
48Documentation/admin-guide/sysctl/index.rst.
49
50.. See scripts/check-sysctl-docs to keep this up to date:
51.. scripts/check-sysctl-docs -vtable="debug" \
52..         $(git grep -l register_sysctl_)
53