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Add RST files covering fips_enabled, fips_name, fips_ver= sion, exception-trace, and kprobes-optimization sysctls. --- Documentation/admin-guide/sysctl/crypto.rst | 59 +++++++++++++++++++ Documentation/admin-guide/sysctl/debug.rst | 63 +++++++++++++++++++++ Documentation/admin-guide/sysctl/index.rst | 8 ++- 3 files changed, 128 insertions(+), 2 deletions(-) create mode 100644 Documentation/admin-guide/sysctl/crypto.rst create mode 100644 Documentation/admin-guide/sysctl/debug.rst diff --git a/Documentation/admin-guide/sysctl/crypto.rst b/Documentation/ad= min-guide/sysctl/crypto.rst new file mode 100644 index 000000000..f44a50f68 --- /dev/null +++ b/Documentation/admin-guide/sysctl/crypto.rst @@ -0,0 +1,59 @@ +.. SPDX-License-Identifier: GPL-2.0 + +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D +Documentation for /proc/sys/crypto/ +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D + +.. See scripts/check-sysctl-docs to keep this up to date: +.. scripts/check-sysctl-docs -vtable=3D"crypto" \ +.. Documentation/admin-guide/sysctl/crypto.rst \ +.. $(git grep -l register_sysctl_) + +Copyright (c) 2026, Shubham Chakraborty + +For general info and legal blurb, please look in +Documentation/admin-guide/sysctl/index.rst. + +--------------------------------------------------------------------------= ---- + +This file contains documentation for the sysctl files in +``/proc/sys/crypto/``. + +The files in this directory can be used to monitor and configure the +Linux kernel's cryptographic subsystem. + +Currently, these files might (depending on your configuration) +show up in ``/proc/sys/crypto/``: + +.. contents:: :local: + +fips_enabled +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D + +This file contains a read-only flag that indicates whether FIPS mode is +enabled. + +- ``0``: FIPS mode is disabled (default). +- ``1``: FIPS mode is enabled. + +This value is set at boot time via the ``fips=3D1`` kernel command line +parameter. When enabled, the cryptographic API will restrict the use +of certain algorithms and perform self-tests to ensure compliance with +FIPS (Federal Information Processing Standards) requirements, such as +FIPS 140-2 and the newer FIPS 140-3, depending on the kernel +configuration and the module in use. + +fips_name +=3D=3D=3D=3D=3D=3D=3D=3D=3D + +This read-only file contains the name of the FIPS module currently in use. +The value is typically configured via the ``CONFIG_CRYPTO_FIPS_NAME`` +kernel configuration option. + +fips_version +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D + +This read-only file contains the version string of the FIPS module. +If ``CONFIG_CRYPTO_FIPS_CUSTOM_VERSION`` is set, it uses the value from +``CONFIG_CRYPTO_FIPS_VERSION``. Otherwise, it defaults to the kernel +release version (``UTS_RELEASE``). diff --git a/Documentation/admin-guide/sysctl/debug.rst b/Documentation/adm= in-guide/sysctl/debug.rst new file mode 100644 index 000000000..1a35042b6 --- /dev/null +++ b/Documentation/admin-guide/sysctl/debug.rst @@ -0,0 +1,63 @@ +.. SPDX-License-Identifier: GPL-2.0 + +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D +Documentation for /proc/sys/debug/ +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D + +.. See scripts/check-sysctl-docs to keep this up to date: +.. scripts/check-sysctl-docs -vtable=3D"debug" \ +.. Documentation/admin-guide/sysctl/debug.rst \ +.. $(git grep -l register_sysctl_) + +Copyright (c) 2026, Shubham Chakraborty + +For general info and legal blurb, please look in +Documentation/admin-guide/sysctl/index.rst. + +--------------------------------------------------------------------------= ---- + +This file contains documentation for the sysctl files in +``/proc/sys/debug/``. + +The files in this directory are used to control various debugging +features within the Linux kernel. + +Currently, these files might (depending on your configuration) +show up in ``/proc/sys/debug/``: + +.. contents:: :local: + +exception-trace +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D + +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 +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D + +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. diff --git a/Documentation/admin-guide/sysctl/index.rst b/Documentation/adm= in-guide/sysctl/index.rst index 4dd2c9b5d..8b51edcf8 100644 --- a/Documentation/admin-guide/sysctl/index.rst +++ b/Documentation/admin-guide/sysctl/index.rst @@ -1,3 +1,5 @@ +.. SPDX-License-Identifier: GPL-2.0 + =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D Documentation for /proc/sys =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D @@ -67,8 +69,8 @@ This documentation is about: =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D abi/ execution domains & personalities <$ARCH> tuning controls for various CPU architecture (e.g. csky, s390) -crypto/ -debug/ +crypto/ cryptographic subsystem +debug/ debugging features dev/ device specific information (e.g. dev/cdrom/info) fs/ specific filesystems filehandle, inode, dentry and quota tuning @@ -96,6 +98,8 @@ it :-) :maxdepth: 1 =20 abi + crypto + debug fs kernel net --=20 2.53.0