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authorChangbin Du <changbin.du@gmail.com>2019-05-08 15:21:20 (GMT)
committerJonathan Corbet <corbet@lwn.net>2019-05-08 20:34:09 (GMT)
commitc2dea5cda0729fdd91760cdad6bb1166037be74a (patch)
treef8849813b53efa8943c3e9ae2908e0d77ab006dd /Documentation/x86
parentac2b4687dadd4e7703c0e985f5a5a0fdaab53316 (diff)
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Documentation: x86: convert entry_64.txt to reST
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'Documentation/x86')
-rw-r--r--Documentation/x86/entry_64.rst (renamed from Documentation/x86/entry_64.txt)12
-rw-r--r--Documentation/x86/index.rst1
2 files changed, 10 insertions, 3 deletions
diff --git a/Documentation/x86/entry_64.txt b/Documentation/x86/entry_64.rst
index c1df8eb..a48b3f6 100644
--- a/Documentation/x86/entry_64.txt
+++ b/Documentation/x86/entry_64.rst
@@ -1,3 +1,9 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+==============
+Kernel Entries
+==============
+
This file documents some of the kernel entries in
arch/x86/entry/entry_64.S. A lot of this explanation is adapted from
an email from Ingo Molnar:
@@ -59,7 +65,7 @@ Now, there's a secondary complication: there's a cheap way to test
which mode the CPU is in and an expensive way.
The cheap way is to pick this info off the entry frame on the kernel
-stack, from the CS of the ptregs area of the kernel stack:
+stack, from the CS of the ptregs area of the kernel stack::
xorl %ebx,%ebx
testl $3,CS+8(%rsp)
@@ -67,7 +73,7 @@ stack, from the CS of the ptregs area of the kernel stack:
SWAPGS
The expensive (paranoid) way is to read back the MSR_GS_BASE value
-(which is what SWAPGS modifies):
+(which is what SWAPGS modifies)::
movl $1,%ebx
movl $MSR_GS_BASE,%ecx
@@ -76,7 +82,7 @@ The expensive (paranoid) way is to read back the MSR_GS_BASE value
js 1f /* negative -> in kernel */
SWAPGS
xorl %ebx,%ebx
-1: ret
+ 1: ret
If we are at an interrupt or user-trap/gate-alike boundary then we can
use the faster check: the stack will be a reliable indicator of
diff --git a/Documentation/x86/index.rst b/Documentation/x86/index.rst
index f6f4e0f..0e3e734 100644
--- a/Documentation/x86/index.rst
+++ b/Documentation/x86/index.rst
@@ -12,3 +12,4 @@ x86-specific Documentation
topology
exception-tables
kernel-stacks
+ entry_64