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-rw-r--r--Documentation/userspace-api/netlink/intro-specs.rst4
-rw-r--r--Documentation/userspace-api/spec_ctrl.rst6
2 files changed, 7 insertions, 3 deletions
diff --git a/Documentation/userspace-api/netlink/intro-specs.rst b/Documentation/userspace-api/netlink/intro-specs.rst
index a4435ae4628d..e5ebc617754a 100644
--- a/Documentation/userspace-api/netlink/intro-specs.rst
+++ b/Documentation/userspace-api/netlink/intro-specs.rst
@@ -13,10 +13,10 @@ Simple CLI
Kernel comes with a simple CLI tool which should be useful when
developing Netlink related code. The tool is implemented in Python
and can use a YAML specification to issue Netlink requests
-to the kernel. Only Generic Netlink is supported.
+to the kernel.
The tool is located at ``tools/net/ynl/pyynl/cli.py``. It accepts
-a handul of arguments, the most important ones are:
+a handful of arguments, the most important ones are:
- ``--spec`` - point to the spec file
- ``--do $name`` / ``--dump $name`` - issue request ``$name``
diff --git a/Documentation/userspace-api/spec_ctrl.rst b/Documentation/userspace-api/spec_ctrl.rst
index 5e8ed9eef9aa..ca89151fc0a8 100644
--- a/Documentation/userspace-api/spec_ctrl.rst
+++ b/Documentation/userspace-api/spec_ctrl.rst
@@ -26,7 +26,8 @@ PR_GET_SPECULATION_CTRL
PR_GET_SPECULATION_CTRL returns the state of the speculation misfeature
which is selected with arg2 of prctl(2). The return value uses bits 0-3 with
-the following meaning:
+the following meaning (with the caveat that PR_SPEC_L1D_FLUSH has less obvious
+semantics, see documentation for that specific control below):
==== ====================== ==================================================
Bit Define Description
@@ -110,6 +111,9 @@ Speculation misfeature controls
- PR_SPEC_L1D_FLUSH: Flush L1D Cache on context switch out of the task
(works only when tasks run on non SMT cores)
+For this control, PR_SPEC_ENABLE means that the **mitigation** is enabled (L1D
+is flushed), PR_SPEC_DISABLE means it is disabled.
+
Invocations:
* prctl(PR_GET_SPECULATION_CTRL, PR_SPEC_L1D_FLUSH, 0, 0, 0);
* prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_L1D_FLUSH, PR_SPEC_ENABLE, 0, 0);