X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=arch%2Fx86%2FKconfig;h=99c3ddd007ce8dac53b0e9b565a4352858dd30b9;hb=fd2615908dfd0586ea40692a99c44e34b7e869bc;hp=4d27bdc85bf226c39fd4b2f07c60b86f74c47f4d;hpb=b41d62201b9772c7c750360ab668d2caa502e642;p=platform%2Fkernel%2Flinux-rpi.git

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 4d27bdc..99c3ddd 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -24,7 +24,7 @@ config X86_64
 	depends on 64BIT
 	# Options that are inherently 64-bit kernel only:
 	select ARCH_HAS_GIGANTIC_PAGE
-	select ARCH_SUPPORTS_INT128
+	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
 	select ARCH_USE_CMPXCHG_LOCKREF
 	select HAVE_ARCH_SOFT_DIRTY
 	select MODULES_USE_ELF_RELA
@@ -1910,6 +1910,51 @@ config X86_INTEL_MEMORY_PROTECTION_KEYS
 
 	  If unsure, say y.
 
+choice
+	prompt "TSX enable mode"
+	depends on CPU_SUP_INTEL
+	default X86_INTEL_TSX_MODE_OFF
+	help
+	  Intel's TSX (Transactional Synchronization Extensions) feature
+	  allows to optimize locking protocols through lock elision which
+	  can lead to a noticeable performance boost.
+
+	  On the other hand it has been shown that TSX can be exploited
+	  to form side channel attacks (e.g. TAA) and chances are there
+	  will be more of those attacks discovered in the future.
+
+	  Therefore TSX is not enabled by default (aka tsx=off). An admin
+	  might override this decision by tsx=on the command line parameter.
+	  Even with TSX enabled, the kernel will attempt to enable the best
+	  possible TAA mitigation setting depending on the microcode available
+	  for the particular machine.
+
+	  This option allows to set the default tsx mode between tsx=on, =off
+	  and =auto. See Documentation/admin-guide/kernel-parameters.txt for more
+	  details.
+
+	  Say off if not sure, auto if TSX is in use but it should be used on safe
+	  platforms or on if TSX is in use and the security aspect of tsx is not
+	  relevant.
+
+config X86_INTEL_TSX_MODE_OFF
+	bool "off"
+	help
+	  TSX is disabled if possible - equals to tsx=off command line parameter.
+
+config X86_INTEL_TSX_MODE_ON
+	bool "on"
+	help
+	  TSX is always enabled on TSX capable HW - equals the tsx=on command
+	  line parameter.
+
+config X86_INTEL_TSX_MODE_AUTO
+	bool "auto"
+	help
+	  TSX is enabled on TSX capable HW that is believed to be safe against
+	  side channel attacks- equals the tsx=auto command line parameter.
+endchoice
+
 config EFI
 	bool "EFI runtime service support"
 	depends on ACPI