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+.. SPDX-License-Identifier: GPL-2.0
+
+.. _kernelparameters:
+
+The kernel's command-line parameters
+====================================
+
+The following is a consolidated list of the kernel parameters as implemented
+by the __setup(), early_param(), core_param() and module_param() macros
+and sorted into English Dictionary order (defined as ignoring all
+punctuation and sorting digits before letters in a case insensitive
+manner), and with descriptions where known.
+
+The kernel parses parameters from the kernel command line up to "``--``";
+if it doesn't recognize a parameter and it doesn't contain a '.', the
+parameter gets passed to init: parameters with '=' go into init's
+environment, others are passed as command line arguments to init.
+Everything after "``--``" is passed as an argument to init.
+
+Module parameters can be specified in two ways: via the kernel command
+line with a module name prefix, or via modprobe, e.g.::
+
+	(kernel command line) usbcore.blinkenlights=1
+	(modprobe command line) modprobe usbcore blinkenlights=1
+
+Parameters for modules which are built into the kernel need to be
+specified on the kernel command line.  modprobe looks through the
+kernel command line (/proc/cmdline) and collects module parameters
+when it loads a module, so the kernel command line can be used for
+loadable modules too.
+
+This document may not be entirely up to date and comprehensive. The command
+"modinfo -p ${modulename}" shows a current list of all parameters of a loadable
+module. Loadable modules, after being loaded into the running kernel, also
+reveal their parameters in /sys/module/${modulename}/parameters/. Some of these
+parameters may be changed at runtime by the command
+``echo -n ${value} > /sys/module/${modulename}/parameters/${parm}``.
+
+Special handling
+----------------
+
+Hyphens (dashes) and underscores are equivalent in parameter names, so::
+
+	log_buf_len=1M print-fatal-signals=1
+
+can also be entered as::
+
+	log-buf-len=1M print_fatal_signals=1
+
+Double-quotes can be used to protect spaces in values, e.g.::
+
+	param="spaces in here"
+
+cpu lists
+~~~~~~~~~
+
+Some kernel parameters take a list of CPUs as a value, e.g.  isolcpus,
+nohz_full, irqaffinity, rcu_nocbs.  The format of this list is:
+
+	<cpu number>,...,<cpu number>
+
+or
+
+	<cpu number>-<cpu number>
+	(must be a positive range in ascending order)
+
+or a mixture
+
+<cpu number>,...,<cpu number>-<cpu number>
+
+Note that for the special case of a range one can split the range into equal
+sized groups and for each group use some amount from the beginning of that
+group:
+
+	<cpu number>-<cpu number>:<used size>/<group size>
+
+For example one can add to the command line following parameter:
+
+	isolcpus=1,2,10-20,100-2000:2/25
+
+where the final item represents CPUs 100,101,125,126,150,151,...
+
+The value "N" can be used to represent the numerically last CPU on the system,
+i.e "foo_cpus=16-N" would be equivalent to "16-31" on a 32 core system.
+
+Keep in mind that "N" is dynamic, so if system changes cause the bitmap width
+to change, such as less cores in the CPU list, then N and any ranges using N
+will also change.  Use the same on a small 4 core system, and "16-N" becomes
+"16-3" and now the same boot input will be flagged as invalid (start > end).
+
+The special case-tolerant group name "all" has a meaning of selecting all CPUs,
+so that "nohz_full=all" is the equivalent of "nohz_full=0-N".
+
+The semantics of "N" and "all" is supported on a level of bitmaps and holds for
+all users of bitmap_parselist().
+
+Metric suffixes
+~~~~~~~~~~~~~~~
+
+The [KMG] suffix is commonly described after a number of kernel
+parameter values. 'K', 'M', 'G', 'T', 'P', and 'E' suffixes are allowed.
+These letters represent the _binary_ multipliers 'Kilo', 'Mega', 'Giga',
+'Tera', 'Peta', and 'Exa', equaling 2^10, 2^20, 2^30, 2^40, 2^50, and
+2^60 bytes respectively. Such letter suffixes can also be entirely omitted.
+
+Kernel Build Options
+--------------------
+
+The parameters listed below are only valid if certain kernel build options
+were enabled and if respective hardware is present. This list should be kept
+in alphabetical order. The text in square brackets at the beginning
+of each description states the restrictions within which a parameter
+is applicable.
+
+Parameters denoted with BOOT are actually interpreted by the boot
+loader, and have no meaning to the kernel directly.
+Do not modify the syntax of boot loader parameters without extreme
+need or coordination with <Documentation/arch/x86/boot.rst>.
+
+There are also arch-specific kernel-parameters not documented here.
+
+Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
+a trailing = on the name of any parameter states that the parameter will
+be entered as an environment variable, whereas its absence indicates that
+it will appear as a kernel argument readable via /proc/cmdline by programs
+running once the system is up.
+
+The number of kernel parameters is not limited, but the length of the
+complete command line (parameters including spaces etc.) is limited to
+a fixed number of characters. This limit depends on the architecture
+and is between 256 and 4096 characters. It is defined in the file
+./include/uapi/asm-generic/setup.h as COMMAND_LINE_SIZE.
+
+.. include:: kernel-parameters.txt
+   :literal: