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-rw-r--r--Documentation/sysctl/ctl_unnumbered.txt22
-rw-r--r--Documentation/sysctl/kernel.txt37
-rw-r--r--Documentation/sysctl/vm.txt2
3 files changed, 35 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..3894eaa23486 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -19,6 +19,8 @@ Currently, these files might (depending on your configuration)
19show up in /proc/sys/kernel: 19show up in /proc/sys/kernel:
20- acpi_video_flags 20- acpi_video_flags
21- acct 21- acct
22- bootloader_type [ X86 only ]
23- bootloader_version [ X86 only ]
22- callhome [ S390 only ] 24- callhome [ S390 only ]
23- auto_msgmni 25- auto_msgmni
24- core_pattern 26- core_pattern
@@ -93,6 +95,35 @@ valid for 30 seconds.
93 95
94============================================================== 96==============================================================
95 97
98bootloader_type:
99
100x86 bootloader identification
101
102This gives the bootloader type number as indicated by the bootloader,
103shifted left by 4, and OR'd with the low four bits of the bootloader
104version. The reason for this encoding is that this used to match the
105type_of_loader field in the kernel header; the encoding is kept for
106backwards compatibility. That is, if the full bootloader type number
107is 0x15 and the full version number is 0x234, this file will contain
108the value 340 = 0x154.
109
110See the type_of_loader and ext_loader_type fields in
111Documentation/x86/boot.txt for additional information.
112
113==============================================================
114
115bootloader_version:
116
117x86 bootloader version
118
119The complete bootloader version number. In the example above, this
120file will contain the value 564 = 0x234.
121
122See the type_of_loader and ext_loader_ver fields in
123Documentation/x86/boot.txt for additional information.
124
125==============================================================
126
96callhome: 127callhome:
97 128
98Controls the kernel's callhome behavior in case of a kernel panic. 129Controls the kernel's callhome behavior in case of a kernel panic.
@@ -139,9 +170,9 @@ core_pattern is used to specify a core dumpfile pattern name.
139core_pipe_limit: 170core_pipe_limit:
140 171
141This sysctl is only applicable when core_pattern is configured to pipe core 172This 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 '|', 173files 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 174see above). When collecting cores via a pipe to an application, it is
144occasionally usefull for the collecting application to gather data about the 175occasionally useful for the collecting application to gather data about the
145crashing process from its /proc/pid directory. In order to do this safely, the 176crashing 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 177kernel 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 178crashing processes proc files prematurely. This in turn creates the possibility
@@ -152,7 +183,7 @@ 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 183processes 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 184skipped. 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 185captured 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 186process is not guaranteed access to /proc/<crashing pid>/). This value defaults
156to 0. 187to 0.
157 188
158============================================================== 189==============================================================
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