arm64: errata: Hide CTR_EL0.DIC on systems affected by Neoverse-N1 #1542419
Cores affected by Neoverse-N1 #1542419 could execute a stale instruction
when a branch is updated to point to freshly generated instructions.
To workaround this issue we need user-space to issue unnecessary
icache maintenance that we can trap. Start by hiding CTR_EL0.DIC.
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 950a56b..7c3e3e3 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -558,6 +558,22 @@
If unsure, say Y.
+config ARM64_ERRATUM_1542419
+ bool "Neoverse-N1: workaround mis-ordering of instruction fetches"
+ default y
+ help
+ This option adds a workaround for ARM Neoverse-N1 erratum
+ 1542419.
+
+ Affected Neoverse-N1 cores could execute a stale instruction when
+ modified by another CPU. The workaround depends on a firmware
+ counterpart.
+
+ Workaround the issue by hiding the DIC feature from EL0. This
+ forces user-space to perform cache maintenance.
+
+ If unsure, say Y.
+
config CAVIUM_ERRATUM_22375
bool "Cavium erratum 22375, 24313"
default y