Commit 86e39b94 authored by Breno Leitao's avatar Breno Leitao Committed by Dave Hansen
Browse files

x86/bugs: Correct RSB terminology in Kconfig 

RSB stands for "Return Stack Buffer" in industry literature[1]. Update
the kernel Kconfig to use this standard term instead of the current
"Return-Speculation-Buffer".

This change aligns kernel documentation with widely accepted terminology.

The line length reduction triggers text reformatting, but no functional
text is altered.

[1] https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/advisory-guidance/return-stack-buffer-underflow.html



Signed-off-by: default avatarBreno Leitao <leitao@debian.org>
Signed-off-by: default avatarDave Hansen <dave.hansen@linux.intel.com>
Acked-by: default avatarDave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20240913122754.249306-1-leitao%40debian.org
parent 9852d85e

arch/x86/Kconfig

+8 −9
Original line number Diff line number Diff line
@@ -2551,15 +2551,14 @@ config MITIGATION_CALL_DEPTH_TRACKING 
	default y

	help

	  Compile the kernel with call depth tracking to mitigate the Intel

	  SKL Return-Speculation-Buffer (RSB) underflow issue. The

	  mitigation is off by default and needs to be enabled on the

	  kernel command line via the retbleed=stuff option. For

	  non-affected systems the overhead of this option is marginal as

	  the call depth tracking is using run-time generated call thunks

	  in a compiler generated padding area and call patching. This

	  increases text size by ~5%. For non affected systems this space

	  is unused. On affected SKL systems this results in a significant

	  performance gain over the IBRS mitigation.

	  SKL Return-Stack-Buffer (RSB) underflow issue. The mitigation is off

	  by default and needs to be enabled on the kernel command line via the

	  retbleed=stuff option. For non-affected systems the overhead of this

	  option is marginal as the call depth tracking is using run-time

	  generated call thunks in a compiler generated padding area and call

	  patching. This increases text size by ~5%. For non affected systems

	  this space is unused. On affected SKL systems this results in a

	  significant performance gain over the IBRS mitigation.



config CALL_THUNKS_DEBUG

	bool "Enable call thunks and call depth tracking debugging"