Documentation: refresh sysctl/kernel.txt

Refresh sysctl/kernel.txt.  More specifically,

 - drop stale index entries
 - sync and sort index and entries
 - reflow sticking out paragraphs to colwidth 72
 - correct typos
 - cleanup whitespace
Signed-off-by: NBorislav Petkov <bp@alien8.de>
Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Documentation/sysctl/kernel.txt

@@ -17,23 +17,21 @@ before actually making adjustments.
 
 Currently, these files might (depending on your configuration)
 show up in /proc/sys/kernel:
-- acpi_video_flags
+
 - acct
+- acpi_video_flags
+- auto_msgmni
 - bootloader_type	     [ X86 only ]
 - bootloader_version	     [ X86 only ]
 - callhome		     [ S390 only ]
-- auto_msgmni
 - core_pattern
 - core_pipe_limit
 - core_uses_pid
 - ctrl-alt-del
-- dentry-state
 - dmesg_restrict
 - domainname
 - hostname
 - hotplug
-- java-appletviewer           [ binfmt_java, obsolete ]
-- java-interpreter            [ binfmt_java, obsolete ]
 - kptr_restrict
 - kstack_depth_to_print       [ X86 only ]
 - l2cr                        [ PPC only ]
@@ -48,10 +46,14 @@ show up in /proc/sys/kernel:
 - overflowgid
 - overflowuid
 - panic
+- panic_on_oops
+- panic_on_unrecovered_nmi
 - pid_max
 - powersave-nap               [ PPC only ]
-- panic_on_unrecovered_nmi
 - printk
+- printk_delay
+- printk_ratelimit
+- printk_ratelimit_burst
 - randomize_va_space
 - real-root-dev               ==> Documentation/initrd.txt
 - reboot-cmd                  [ SPARC only ]
@@ -62,6 +64,7 @@ show up in /proc/sys/kernel:
 - shmall
 - shmmax                      [ sysv ipc ]
 - shmmni
+- softlockup_thresh
 - stop-a                      [ SPARC only ]
 - sysrq                       ==> Documentation/sysrq.txt
 - tainted
@@ -71,15 +74,6 @@ show up in /proc/sys/kernel:
 
 ==============================================================
 
-acpi_video_flags:
-
-flags
-
-See Doc*/kernel/power/video.txt, it allows mode of video boot to be
-set during run time.
-
-==============================================================
-
 acct:
 
 highwater lowwater frequency
@@ -95,6 +89,25 @@ That is, suspend accounting if there left <= 2% free; resume it
 if we got >=4%; consider information about amount of free space
 valid for 30 seconds.
 
+==============================================================
+
+acpi_video_flags:
+
+flags
+
+See Doc*/kernel/power/video.txt, it allows mode of video boot to be
+set during run time.
+
+==============================================================
+
+auto_msgmni:
+
+Enables/Disables automatic recomputing of msgmni upon memory add/remove
+or upon ipc namespace creation/removal (see the msgmni description
+above). Echoing "1" into this file enables msgmni automatic recomputing.
+Echoing "0" turns it off. auto_msgmni default value is 1.
+
+
 ==============================================================
 
 bootloader_type:
@@ -172,22 +185,24 @@ core_pattern is used to specify a core dumpfile pattern name.
 
 core_pipe_limit:
 
-This sysctl is only applicable when core_pattern is configured to pipe core
-files to a user space helper (when the first character of core_pattern is a '|',
-see above).  When collecting cores via a pipe to an application, it is
-occasionally useful for the collecting application to gather data about the
-crashing process from its /proc/pid directory.  In order to do this safely, the
-kernel must wait for the collecting process to exit, so as not to remove the
-crashing processes proc files prematurely.  This in turn creates the possibility
-that a misbehaving userspace collecting process can block the reaping of a
-crashed process simply by never exiting.  This sysctl defends against that.  It
-defines how many concurrent crashing processes may be piped to user space
-applications in parallel.  If this value is exceeded, then those crashing
-processes above that value are noted via the kernel log and their cores are
-skipped.  0 is a special value, indicating that unlimited processes may be
-captured in parallel, but that no waiting will take place (i.e. the collecting
-process is not guaranteed access to /proc/<crashing pid>/).  This value defaults
-to 0.
+This sysctl is only applicable when core_pattern is configured to pipe
+core files to a user space helper (when the first character of
+core_pattern is a '|', see above).  When collecting cores via a pipe
+to an application, it is occasionally useful for the collecting
+application to gather data about the crashing process from its
+/proc/pid directory.  In order to do this safely, the kernel must wait
+for the collecting process to exit, so as not to remove the crashing
+processes proc files prematurely.  This in turn creates the
+possibility that a misbehaving userspace collecting process can block
+the reaping of a crashed process simply by never exiting.  This sysctl
+defends against that.  It defines how many concurrent crashing
+processes may be piped to user space applications in parallel.  If
+this value is exceeded, then those crashing processes above that value
+are noted via the kernel log and their cores are skipped.  0 is a
+special value, indicating that unlimited processes may be captured in
+parallel, but that no waiting will take place (i.e. the collecting
+process is not guaranteed access to /proc/<crashing pid>/).  This
+value defaults to 0.
 
 ==============================================================
 
@@ -218,14 +233,14 @@ to decide what to do with it.
 
 dmesg_restrict:
 
-This toggle indicates whether unprivileged users are prevented from using
-dmesg(8) to view messages from the kernel's log buffer.  When
-dmesg_restrict is set to (0) there are no restrictions.  When
+This toggle indicates whether unprivileged users are prevented
+from using dmesg(8) to view messages from the kernel's log buffer.
+When dmesg_restrict is set to (0) there are no restrictions. When
 dmesg_restrict is set set to (1), users must have CAP_SYSLOG to use
 dmesg(8).
 
-The kernel config option CONFIG_SECURITY_DMESG_RESTRICT sets the default
-value of dmesg_restrict.
+The kernel config option CONFIG_SECURITY_DMESG_RESTRICT sets the
+default value of dmesg_restrict.
 
 ==============================================================
 
@@ -256,13 +271,6 @@ Default value is "/sbin/hotplug".
 
 ==============================================================
 
-l2cr: (PPC only)
-
-This flag controls the L2 cache of G3 processor boards. If
-0, the cache is disabled. Enabled if nonzero.
-
-==============================================================
-
 kptr_restrict:
 
 This toggle indicates whether restrictions are placed on
@@ -283,6 +291,13 @@ kernel stack.
 
 ==============================================================
 
+l2cr: (PPC only)
+
+This flag controls the L2 cache of G3 processor boards. If
+0, the cache is disabled. Enabled if nonzero.
+
+==============================================================
+
 modules_disabled:
 
 A toggle value indicating if modules are allowed to be loaded
@@ -293,6 +308,21 @@ to false.
 
 ==============================================================
 
+nmi_watchdog:
+
+Enables/Disables the NMI watchdog on x86 systems. When the value is
+non-zero the NMI watchdog is enabled and will continuously test all
+online cpus to determine whether or not they are still functioning
+properly. Currently, passing "nmi_watchdog=" parameter at boot time is
+required for this function to work.
+
+If LAPIC NMI watchdog method is in use (nmi_watchdog=2 kernel
+parameter), the NMI watchdog shares registers with oprofile. By
+disabling the NMI watchdog, oprofile may have more registers to
+utilize.
+
+==============================================================
+
 osrelease, ostype & version:
 
 # cat osrelease
@@ -312,10 +342,10 @@ The only way to tune these values is to rebuild the kernel :-)
 
 overflowgid & overflowuid:
 
-if your architecture did not always support 32-bit UIDs (i.e. arm, i386,
-m68k, sh, and sparc32), a fixed UID and GID will be returned to
-applications that use the old 16-bit UID/GID system calls, if the actual
-UID or GID would exceed 65535.
+if your architecture did not always support 32-bit UIDs (i.e. arm,
+i386, m68k, sh, and sparc32), a fixed UID and GID will be returned to
+applications that use the old 16-bit UID/GID system calls, if the
+actual UID or GID would exceed 65535.
 
 These sysctls allow you to change the value of the fixed UID and GID.
 The default is 65534.
@@ -324,9 +354,22 @@ The default is 65534.
 
 panic:
 
-The value in this file represents the number of seconds the
-kernel waits before rebooting on a panic. When you use the
-software watchdog, the recommended setting is 60.
+The value in this file represents the number of seconds the kernel
+waits before rebooting on a panic. When you use the software watchdog,
+the recommended setting is 60.
+
+==============================================================
+
+panic_on_unrecovered_nmi:
+
+The default Linux behaviour on an NMI of either memory or unknown is
+to continue operation. For many environments such as scientific
+computing it is preferable that the box is taken out and the error
+dealt with than an uncorrected parity/ECC error get propagated.
+
+A small number of systems do generate NMI's for bizarre random reasons
+such as power management so the default is off. That sysctl works like
+the existing panic controls already in that directory.
 
 ==============================================================
 
@@ -376,6 +419,14 @@ the different loglevels.
 
 ==============================================================
 
+printk_delay:
+
+Delay each printk message in printk_delay milliseconds
+
+Value from 0 - 10000 is allowed.
+
+==============================================================
+
 printk_ratelimit:
 
 Some warning messages are rate limited. printk_ratelimit specifies
@@ -395,15 +446,7 @@ send before ratelimiting kicks in.
 
 ==============================================================
 
-printk_delay:
-
-Delay each printk message in printk_delay milliseconds
-
-Value from 0 - 10000 is allowed.
-
-==============================================================
-
-randomize-va-space:
+randomize_va_space:
 
 This option can be used to select the type of process address
 space randomization that is used in the system, for architectures
@@ -466,11 +509,11 @@ are doing anyway :)
 
 ==============================================================
 
-shmmax: 
+shmmax:
 
 This value can be used to query and set the run time limit
 on the maximum shared memory segment size that can be created.
-Shared memory segments up to 1Gb are now supported in the 
+Shared memory segments up to 1Gb are now supported in the
 kernel.  This value defaults to SHMMAX.
 
 ==============================================================
@@ -484,7 +527,7 @@ tunable to zero will disable the softlockup detection altogether.
 
 ==============================================================
 
-tainted: 
+tainted:
 
 Non-zero if the kernel has been tainted.  Numeric values, which
 can be ORed together:
@@ -509,49 +552,11 @@ can be ORed together:
 
 ==============================================================
 
-auto_msgmni:
-
-Enables/Disables automatic recomputing of msgmni upon memory add/remove or
-upon ipc namespace creation/removal (see the msgmni description above).
-Echoing "1" into this file enables msgmni automatic recomputing.
-Echoing "0" turns it off.
-auto_msgmni default value is 1.
-
-==============================================================
-
-nmi_watchdog:
-
-Enables/Disables the NMI watchdog on x86 systems.  When the value is non-zero
-the NMI watchdog is enabled and will continuously test all online cpus to
-determine whether or not they are still functioning properly. Currently,
-passing "nmi_watchdog=" parameter at boot time is required for this function
-to work.
-
-If LAPIC NMI watchdog method is in use (nmi_watchdog=2 kernel parameter), the
-NMI watchdog shares registers with oprofile. By disabling the NMI watchdog,
-oprofile may have more registers to utilize.
-
-==============================================================
-
 unknown_nmi_panic:
 
-The value in this file affects behavior of handling NMI. When the value is
-non-zero, unknown NMI is trapped and then panic occurs. At that time, kernel
-debugging information is displayed on console.
-
-NMI switch that most IA32 servers have fires unknown NMI up, for example.
-If a system hangs up, try pressing the NMI switch.
-
-==============================================================
-
-panic_on_unrecovered_nmi:
-
-The default Linux behaviour on an NMI of either memory or unknown is to continue
-operation. For many environments such as scientific computing it is preferable
-that the box is taken out and the error dealt with than an uncorrected
-parity/ECC error get propogated.
-
-A small number of systems do generate NMI's for bizarre random reasons such as
-power management so the default is off. That sysctl works like the existing
-panic controls already in that directory.
+The value in this file affects behavior of handling NMI. When the
+value is non-zero, unknown NMI is trapped and then panic occurs. At
+that time, kernel debugging information is displayed on console.
 
+NMI switch that most IA32 servers have fires unknown NMI up, for
+example.  If a system hangs up, try pressing the NMI switch.