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-rw-r--r--Documentation/sysctl/ctl_unnumbered.txt22
-rw-r--r--Documentation/sysctl/kernel.txt6
-rw-r--r--Documentation/sysctl/vm.txt2
3 files changed, 4 insertions, 26 deletions
diff --git a/Documentation/sysctl/ctl_unnumbered.txt b/Documentation/sysctl/ctl_unnumbered.txt
deleted file mode 100644
index 23003a8ea3e7..000000000000
--- a/Documentation/sysctl/ctl_unnumbered.txt
+++ /dev/null
@@ -1,22 +0,0 @@
1
2Except for a few extremely rare exceptions user space applications do not use
3the binary sysctl interface. Instead everyone uses /proc/sys/... with
4readable ascii names.
5
6Recently the kernel has started supporting setting the binary sysctl value to
7CTL_UNNUMBERED so we no longer need to assign a binary sysctl path to allow
8sysctls to show up in /proc/sys.
9
10Assigning binary sysctl numbers is an endless source of conflicts in sysctl.h,
11breaking of the user space ABI (because of those conflicts), and maintenance
12problems. A complete pass through all of the sysctl users revealed multiple
13instances where the sysctl binary interface was broken and had gone undetected
14for years.
15
16So please do not add new binary sysctl numbers. They are unneeded and
17problematic.
18
19If you really need a new binary sysctl number please first merge your sysctl
20into the kernel and then as a separate patch allocate a binary sysctl number.
21
22(ebiederm@xmission.com, June 2007)
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index a028b92001ed..8f7a0e73ef44 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -139,9 +139,9 @@ core_pattern is used to specify a core dumpfile pattern name.
139core_pipe_limit: 139core_pipe_limit:
140 140
141This sysctl is only applicable when core_pattern is configured to pipe core 141This sysctl is only applicable when core_pattern is configured to pipe core
142files to user space helper a (when the first character of core_pattern is a '|', 142files to a user space helper (when the first character of core_pattern is a '|',
143see above). When collecting cores via a pipe to an application, it is 143see above). When collecting cores via a pipe to an application, it is
144occasionally usefull for the collecting application to gather data about the 144occasionally useful for the collecting application to gather data about the
145crashing process from its /proc/pid directory. In order to do this safely, the 145crashing process from its /proc/pid directory. In order to do this safely, the
146kernel must wait for the collecting process to exit, so as not to remove the 146kernel must wait for the collecting process to exit, so as not to remove the
147crashing processes proc files prematurely. This in turn creates the possibility 147crashing processes proc files prematurely. This in turn creates the possibility
@@ -152,7 +152,7 @@ applications in parallel. If this value is exceeded, then those crashing
152processes above that value are noted via the kernel log and their cores are 152processes above that value are noted via the kernel log and their cores are
153skipped. 0 is a special value, indicating that unlimited processes may be 153skipped. 0 is a special value, indicating that unlimited processes may be
154captured in parallel, but that no waiting will take place (i.e. the collecting 154captured in parallel, but that no waiting will take place (i.e. the collecting
155process is not guaranteed access to /proc/<crahing pid>/). This value defaults 155process is not guaranteed access to /proc/<crashing pid>/). This value defaults
156to 0. 156to 0.
157 157
158============================================================== 158==============================================================
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index a6e360d2055c..fc5790d36cd9 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -370,7 +370,7 @@ The default is 1 percent.
370mmap_min_addr 370mmap_min_addr
371 371
372This file indicates the amount of address space which a user process will 372This file indicates the amount of address space which a user process will
373be restricted from mmaping. Since kernel null dereference bugs could 373be restricted from mmapping. Since kernel null dereference bugs could
374accidentally operate based on the information in the first couple of pages 374accidentally operate based on the information in the first couple of pages
375of memory userspace processes should not be allowed to write to them. By 375of memory userspace processes should not be allowed to write to them. By
376default this value is set to 0 and no protections will be enforced by the 376default this value is set to 0 and no protections will be enforced by the