Commit 8f7c0d8b authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Peter Zijlstra
Browse files

x86/Kconfig: Add CONFIG_CALL_THUNKS 



In preparation for mitigating the Intel SKL RSB underflow issue in
software, add a new configuration symbol which allows to build the
required call thunk infrastructure conditionally.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220915111146.849523555@infradead.org
parent cb855971

arch/x86/Kconfig

+8 −0
Original line number Diff line number Diff line
@@ -2446,6 +2446,14 @@ config CC_HAS_SLS 
config CC_HAS_RETURN_THUNK

	def_bool $(cc-option,-mfunction-return=thunk-extern)



config HAVE_CALL_THUNKS

	def_bool y

	depends on RETHUNK && OBJTOOL



config CALL_THUNKS

	def_bool n

	select FUNCTION_ALIGNMENT_16B



menuconfig SPECULATION_MITIGATIONS

	bool "Mitigations for speculative execution vulnerabilities"

	default y