Merge tag 'media/v5.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab...

[linux-2.6-microblaze.git] / Documentation / x86 / entry_64.rst

diff --git a/Documentation/x86/entry_64.rst b/Documentation/x86/entry_64.rst
index b87c1d8..a48b3f6 100644 (file)
--- a/Documentation/x86/entry_64.rst
+++ b/Documentation/x86/entry_64.rst
@@ -108,12 +108,3 @@ We try to only use IST entries and the paranoid entry code for vectors
 that absolutely need the more expensive check for the GS base - and we
 generate all 'normal' entry points with the regular (faster) paranoid=0
 variant.
-
-On a FSGSBASE system, however, user space can set GS without kernel
-interaction. It means the value of GS base itself does not imply anything,
-whether a kernel value or a user space value. So, there is no longer a safe
-way to check whether the exception is entering from user mode or kernel
-mode in the paranoid entry code path. So the GSBASE value needs to be read
-out, saved and the kernel GSBASE value written. On exit the saved GSBASE
-value needs to be restored unconditionally. The non paranoid entry/exit
-code still uses SWAPGS unconditionally as the state is known.