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-rw-r--r--arch/arm64/Kconfig43
1 files changed, 43 insertions, 0 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 86e3ab630aa6..7023e9bbc401 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -429,6 +429,20 @@ config ARM64_ERRATUM_843419
If unsure, say Y.
+config ARM64_ERRATUM_1024718
+ bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
+ default y
+ help
+ This option adds work around for Arm Cortex-A55 Erratum 1024718.
+
+ Affected Cortex-A55 cores (r0p0, r0p1, r1p0) could cause incorrect
+ update of the hardware dirty bit when the DBM/AP bits are updated
+ without a break-before-make. The work around is to disable the usage
+ of hardware DBM locally on the affected cores. CPUs not affected by
+ erratum will continue to use the feature.
+
+ If unsure, say Y.
+
config CAVIUM_ERRATUM_22375
bool "Cavium erratum 22375, 24313"
default y
@@ -746,6 +760,35 @@ config FORCE_MAX_ZONEORDER
However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
4M allocations matching the default size used by generic code.
+config UNMAP_KERNEL_AT_EL0
+ bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
+ default y
+ help
+ Speculation attacks against some high-performance processors can
+ be used to bypass MMU permission checks and leak kernel data to
+ userspace. This can be defended against by unmapping the kernel
+ when running in userspace, mapping it back in on exception entry
+ via a trampoline page in the vector table.
+
+ If unsure, say Y.
+
+config HARDEN_BRANCH_PREDICTOR
+ bool "Harden the branch predictor against aliasing attacks" if EXPERT
+ default y
+ help
+ Speculation attacks against some high-performance processors rely on
+ being able to manipulate the branch predictor for a victim context by
+ executing aliasing branches in the attacker context. Such attacks
+ can be partially mitigated against by clearing internal branch
+ predictor state and limiting the prediction logic in some situations.
+
+ This config option will take CPU-specific actions to harden the
+ branch predictor against aliasing attacks and may rely on specific
+ instruction sequences or control bits being set by the system
+ firmware.
+
+ If unsure, say Y.
+
menuconfig ARMV8_DEPRECATED
bool "Emulate deprecated/obsolete ARMv8 instructions"
depends on COMPAT