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