Merge tag 'for-linus-20180210' of git://git.kernel.dk/linux-block

[sfrench/cifs-2.6.git] / arch / s390 / Kconfig

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 0105ce28e246a766e7348c7a98a733470d3c8a4e..eaee7087886fa290a3b4ca0fbdf379ebf62ee840 100644 (file)
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -112,7 +112,6 @@ config S390
        select ARCH_USE_BUILTIN_BSWAP
        select ARCH_USE_CMPXCHG_LOCKREF
        select ARCH_WANTS_DYNAMIC_TASK_STRUCT
-       select ARCH_WANTS_PROT_NUMA_PROT_NONE
        select ARCH_WANTS_UBSAN_NO_NULL
        select ARCH_WANT_IPC_PARSE_VERSION
        select BUILDTIME_EXTABLE_SORT
@@ -540,6 +539,51 @@ config ARCH_RANDOM
 
          If unsure, say Y.
 
+config KERNEL_NOBP
+       def_bool n
+       prompt "Enable modified branch prediction for the kernel by default"
+       help
+         If this option is selected the kernel will switch to a modified
+         branch prediction mode if the firmware interface is available.
+         The modified branch prediction mode improves the behaviour in
+         regard to speculative execution.
+
+         With the option enabled the kernel parameter "nobp=0" or "nospec"
+         can be used to run the kernel in the normal branch prediction mode.
+
+         With the option disabled the modified branch prediction mode is
+         enabled with the "nobp=1" kernel parameter.
+
+         If unsure, say N.
+
+config EXPOLINE
+       def_bool n
+       prompt "Avoid speculative indirect branches in the kernel"
+       help
+         Compile the kernel with the expoline compiler options to guard
+         against kernel-to-user data leaks by avoiding speculative indirect
+         branches.
+         Requires a compiler with -mindirect-branch=thunk support for full
+         protection. The kernel may run slower.
+
+         If unsure, say N.
+
+choice
+       prompt "Expoline default"
+       depends on EXPOLINE
+       default EXPOLINE_FULL
+
+config EXPOLINE_OFF
+       bool "spectre_v2=off"
+
+config EXPOLINE_MEDIUM
+       bool "spectre_v2=auto"
+
+config EXPOLINE_FULL
+       bool "spectre_v2=on"
+
+endchoice
+
 endmenu
 
 menu "Memory setup"