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-rw-r--r--Documentation/admin-guide/sysctl/abi.rst73
-rw-r--r--Documentation/admin-guide/sysctl/net.rst20
2 files changed, 34 insertions, 59 deletions
diff --git a/Documentation/admin-guide/sysctl/abi.rst b/Documentation/admin-guide/sysctl/abi.rst
index 599bcde7f0b7..ac87eafdb54f 100644
--- a/Documentation/admin-guide/sysctl/abi.rst
+++ b/Documentation/admin-guide/sysctl/abi.rst
@@ -1,67 +1,34 @@
+.. SPDX-License-Identifier: GPL-2.0+
+
================================
Documentation for /proc/sys/abi/
================================
-kernel version 2.6.0.test2
+.. See scripts/check-sysctl-docs to keep this up to date:
+.. scripts/check-sysctl-docs -vtable="abi" \
+.. Documentation/admin-guide/sysctl/abi.rst \
+.. $(git grep -l register_sysctl_)
-Copyright (c) 2003, Fabian Frederick <ffrederick@users.sourceforge.net>
+Copyright (c) 2020, Stephen Kitt
-For general info: index.rst.
+For general info, see :doc:`index`.
------------------------------------------------------------------------------
-This path is binary emulation relevant aka personality types aka abi.
-When a process is executed, it's linked to an exec_domain whose
-personality is defined using values available from /proc/sys/abi.
-You can find further details about abi in include/linux/personality.h.
-
-Here are the files featuring in 2.6 kernel:
-
-- defhandler_coff
-- defhandler_elf
-- defhandler_lcall7
-- defhandler_libcso
-- fake_utsname
-- trace
-
-defhandler_coff
----------------
-
-defined value:
- PER_SCOSVR3::
-
- 0x0003 | STICKY_TIMEOUTS | WHOLE_SECONDS | SHORT_INODE
-
-defhandler_elf
---------------
-
-defined value:
- PER_LINUX::
-
- 0
-
-defhandler_lcall7
------------------
-
-defined value :
- PER_SVR4::
-
- 0x0001 | STICKY_TIMEOUTS | MMAP_PAGE_ZERO,
-
-defhandler_libsco
------------------
-
-defined value:
- PER_SVR4::
+The files in ``/proc/sys/abi`` can be used to see and modify
+ABI-related settings.
- 0x0001 | STICKY_TIMEOUTS | MMAP_PAGE_ZERO,
+Currently, these files might (depending on your configuration)
+show up in ``/proc/sys/kernel``:
-fake_utsname
-------------
+.. contents:: :local:
-Unused
+vsyscall32 (x86)
+================
-trace
------
+Determines whether the kernels maps a vDSO page into 32-bit processes;
+can be set to 1 to enable, or 0 to disable. Defaults to enabled if
+``CONFIG_COMPAT_VDSO`` is set, disabled otherwide.
-Unused
+This controls the same setting as the ``vdso32`` kernel boot
+parameter.
diff --git a/Documentation/admin-guide/sysctl/net.rst b/Documentation/admin-guide/sysctl/net.rst
index 42cd04bca548..57fd6ce68fe0 100644
--- a/Documentation/admin-guide/sysctl/net.rst
+++ b/Documentation/admin-guide/sysctl/net.rst
@@ -300,7 +300,6 @@ Note:
0: 0 1 2 3 4 5 6 7
RSS hash key:
84:50:f4:00:a8:15:d1:a7:e9:7f:1d:60:35:c7:47:25:42:97:74:ca:56:bb:b6:a1:d8:43:e3:c9:0c:fd:17:55:c2:3a:4d:69:ed:f1:42:89
-
netdev_tstamp_prequeue
----------------------
@@ -321,11 +320,20 @@ fb_tunnels_only_for_init_net
----------------------------
Controls if fallback tunnels (like tunl0, gre0, gretap0, erspan0,
-sit0, ip6tnl0, ip6gre0) are automatically created when a new
-network namespace is created, if corresponding tunnel is present
-in initial network namespace.
-If set to 1, these devices are not automatically created, and
-user space is responsible for creating them if needed.
+sit0, ip6tnl0, ip6gre0) are automatically created. There are 3 possibilities
+(a) value = 0; respective fallback tunnels are created when module is
+loaded in every net namespaces (backward compatible behavior).
+(b) value = 1; [kcmd value: initns] respective fallback tunnels are
+created only in init net namespace and every other net namespace will
+not have them.
+(c) value = 2; [kcmd value: none] fallback tunnels are not created
+when a module is loaded in any of the net namespace. Setting value to
+"2" is pointless after boot if these modules are built-in, so there is
+a kernel command-line option that can change this default. Please refer to
+Documentation/admin-guide/kernel-parameters.txt for additional details.
+
+Not creating fallback tunnels gives control to userspace to create
+whatever is needed only and avoid creating devices which are redundant.
Default : 0 (for compatibility reasons)