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-rw-r--r--Documentation/sysctl/fs.txt23
-rw-r--r--Documentation/sysctl/kernel.txt38
-rw-r--r--Documentation/sysctl/vm.txt33
3 files changed, 84 insertions, 10 deletions
diff --git a/Documentation/sysctl/fs.txt b/Documentation/sysctl/fs.txt
index 88152f214..302b5ed61 100644
--- a/Documentation/sysctl/fs.txt
+++ b/Documentation/sysctl/fs.txt
@@ -32,6 +32,8 @@ Currently, these files are in /proc/sys/fs:
- nr_open
- overflowuid
- overflowgid
+- pipe-user-pages-hard
+- pipe-user-pages-soft
- protected_hardlinks
- protected_symlinks
- suid_dumpable
@@ -159,6 +161,27 @@ The default is 65534.
==============================================================
+pipe-user-pages-hard:
+
+Maximum total number of pages a non-privileged user may allocate for pipes.
+Once this limit is reached, no new pipes may be allocated until usage goes
+below the limit again. When set to 0, no limit is applied, which is the default
+setting.
+
+==============================================================
+
+pipe-user-pages-soft:
+
+Maximum total number of pages a non-privileged user may allocate for pipes
+before the pipe size gets limited to a single page. Once this limit is reached,
+new pipes will be limited to a single page in size for this user in order to
+limit total memory usage, and trying to increase them using fcntl() will be
+denied until usage goes below the limit again. The default value allows to
+allocate up to 1024 pipes at their default size. When set to 0, no limit is
+applied.
+
+==============================================================
+
protected_hardlinks:
A long-standing class of security issues is the hardlink-based
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index af70d1541..87119dc9b 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -551,6 +551,21 @@ the recommended setting is 60.
==============================================================
+panic_on_io_nmi:
+
+Controls the kernel's behavior when a CPU receives an NMI caused by
+an IO error.
+
+0: try to continue operation (default)
+
+1: panic immediately. The IO error triggered an NMI. This indicates a
+ serious system condition which could result in IO data corruption.
+ Rather than continuing, panicking might be a better choice. Some
+ servers issue this sort of NMI when the dump button is pushed,
+ and you can use this option to take a crash dump.
+
+==============================================================
+
panic_on_oops:
Controls the kernel's behaviour when an oops or BUG is encountered.
@@ -745,6 +760,14 @@ rtsig-nr shows the number of RT signals currently queued.
==============================================================
+sched_schedstats:
+
+Enables/disables scheduler statistics. Enabling this feature
+incurs a small amount of overhead in the scheduler but is
+useful for debugging and performance tuning.
+
+==============================================================
+
sg-big-buff:
This file shows the size of the generic SCSI (sg) buffer.
@@ -810,14 +833,13 @@ via the /proc/sys interface:
Each write syscall must fully contain the sysctl value to be
written, and multiple writes on the same sysctl file descriptor
will rewrite the sysctl value, regardless of file position.
- 0 - (default) Same behavior as above, but warn about processes that
- perform writes to a sysctl file descriptor when the file position
- is not 0.
- 1 - Respect file position when writing sysctl strings. Multiple writes
- will append to the sysctl value buffer. Anything past the max length
- of the sysctl value buffer will be ignored. Writes to numeric sysctl
- entries must always be at file position 0 and the value must be
- fully contained in the buffer sent in the write syscall.
+ 0 - Same behavior as above, but warn about processes that perform writes
+ to a sysctl file descriptor when the file position is not 0.
+ 1 - (default) Respect file position when writing sysctl strings. Multiple
+ writes will append to the sysctl value buffer. Anything past the max
+ length of the sysctl value buffer will be ignored. Writes to numeric
+ sysctl entries must always be at file position 0 and the value must
+ be fully contained in the buffer sent in the write syscall.
==============================================================
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index f72370b44..89a887c76 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -42,6 +42,8 @@ Currently, these files are in /proc/sys/vm:
- min_slab_ratio
- min_unmapped_ratio
- mmap_min_addr
+- mmap_rnd_bits
+- mmap_rnd_compat_bits
- nr_hugepages
- nr_overcommit_hugepages
- nr_trim_pages (only if CONFIG_MMU=n)
@@ -135,7 +137,7 @@ Contains, as a percentage of total available memory that contains free pages
and reclaimable pages, the number of pages at which the background kernel
flusher threads will start writing out dirty data.
-The total avaiable memory is not equal to total system memory.
+The total available memory is not equal to total system memory.
==============================================================
@@ -170,7 +172,7 @@ Contains, as a percentage of total available memory that contains free pages
and reclaimable pages, the number of pages at which a process which is
generating disk writes will itself start writing out dirty data.
-The total avaiable memory is not equal to total system memory.
+The total available memory is not equal to total system memory.
==============================================================
@@ -485,6 +487,33 @@ against future potential kernel bugs.
==============================================================
+mmap_rnd_bits:
+
+This value can be used to select the number of bits to use to
+determine the random offset to the base address of vma regions
+resulting from mmap allocations on architectures which support
+tuning address space randomization. This value will be bounded
+by the architecture's minimum and maximum supported values.
+
+This value can be changed after boot using the
+/proc/sys/vm/mmap_rnd_bits tunable
+
+==============================================================
+
+mmap_rnd_compat_bits:
+
+This value can be used to select the number of bits to use to
+determine the random offset to the base address of vma regions
+resulting from mmap allocations for applications run in
+compatibility mode on architectures which support tuning address
+space randomization. This value will be bounded by the
+architecture's minimum and maximum supported values.
+
+This value can be changed after boot using the
+/proc/sys/vm/mmap_rnd_compat_bits tunable
+
+==============================================================
+
nr_hugepages
Change the minimum size of the hugepage pool.