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kernel/Documentation/sysctl
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* tag 'ASB-2022-03-05_4.19-stable': (763 commits)
  Linux 4.19.232
  tty: n_gsm: fix encoding of control signal octet bit DV
  xhci: Prevent futile URB re-submissions due to incorrect return value.
  xhci: re-initialize the HC during resume if HCE was set
  usb: dwc3: gadget: Let the interrupt handler disable bottom halves.
  usb: dwc3: pci: Fix Bay Trail phy GPIO mappings
  USB: serial: option: add Telit LE910R1 compositions
  USB: serial: option: add support for DW5829e
  tracefs: Set the group ownership in apply_options() not parse_options()
  USB: gadget: validate endpoint index for xilinx udc
  usb: gadget: rndis: add spinlock for rndis response list
  Revert "USB: serial: ch341: add new Product ID for CH341A"
  ata: pata_hpt37x: disable primary channel on HPT371
  iio: adc: men_z188_adc: Fix a resource leak in an error handling path
  tracing: Have traceon and traceoff trigger honor the instance
  fget: clarify and improve __fget_files() implementation
  memblock: use kfree() to release kmalloced memblock regions
  Revert "drm/nouveau/pmu/gm200-: avoid touching PMU outside of DEVINIT/PREOS/ACR"
  gpio: tegra186: Fix chip_data type confusion
  tty: n_gsm: fix proper link termination after failed open
  ...

Change-Id: I11cf0e2c1fd1318f0985f4783cce8dd4b7c8ae1d
2022-03-08 16:51:11 +08:00
..

Documentation for /proc/sys/		kernel version 2.2.10
	(c) 1998, 1999,  Rik van Riel <riel@nl.linux.org>

'Why', I hear you ask, 'would anyone even _want_ documentation
for them sysctl files? If anybody really needs it, it's all in
the source...'

Well, this documentation is written because some people either
don't know they need to tweak something, or because they don't
have the time or knowledge to read the source code.

Furthermore, the programmers who built sysctl have built it to
be actually used, not just for the fun of programming it :-)

==============================================================

Legal blurb:

As usual, there are two main things to consider:
1. you get what you pay for
2. it's free

The consequences are that I won't guarantee the correctness of
this document, and if you come to me complaining about how you
screwed up your system because of wrong documentation, I won't
feel sorry for you. I might even laugh at you...

But of course, if you _do_ manage to screw up your system using
only the sysctl options used in this file, I'd like to hear of
it. Not only to have a great laugh, but also to make sure that
you're the last RTFMing person to screw up.

In short, e-mail your suggestions, corrections and / or horror
stories to: <riel@nl.linux.org>

Rik van Riel.

==============================================================

Introduction:

Sysctl is a means of configuring certain aspects of the kernel
at run-time, and the /proc/sys/ directory is there so that you
don't even need special tools to do it!
In fact, there are only four things needed to use these config
facilities:
- a running Linux system
- root access
- common sense (this is especially hard to come by these days)
- knowledge of what all those values mean

As a quick 'ls /proc/sys' will show, the directory consists of
several (arch-dependent?) subdirs. Each subdir is mainly about
one part of the kernel, so you can do configuration on a piece
by piece basis, or just some 'thematic frobbing'.

The subdirs are about:
abi/		execution domains & personalities
debug/		<empty>
dev/		device specific information (eg dev/cdrom/info)
fs/		specific filesystems
		filehandle, inode, dentry and quota tuning
		binfmt_misc <Documentation/admin-guide/binfmt-misc.rst>
kernel/		global kernel info / tuning
		miscellaneous stuff
net/		networking stuff, for documentation look in:
		<Documentation/networking/>
proc/		<empty>
sunrpc/		SUN Remote Procedure Call (NFS)
vm/		memory management tuning
		buffer and cache management
user/		Per user per user namespace limits

These are the subdirs I have on my system. There might be more
or other subdirs in another setup. If you see another dir, I'd
really like to hear about it :-)