From: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> Add Memory Tagging Extension support to the arm64 kbuild. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> Co-developed-by: Catalin Marinas <catalin.marinas@xxxxxxx> Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> --- Notes: v6: - Remove select ARCH_USES_PG_ARCH_2, no longer defined. v5: - Remove duplicate ARMv8.5 menu entry. v4: - select ARCH_USES_PG_ARCH_2. - remove ARCH_NO_SWAP. - default y. arch/arm64/Kconfig | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 66dc41fd49f2..ad4d8e4da490 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1664,6 +1664,34 @@ config ARCH_RANDOM provides a high bandwidth, cryptographically secure hardware random number generator. +config ARM64_AS_HAS_MTE + def_bool $(as-instr,.arch armv8.5-a+memtag) + +config ARM64_MTE + bool "Memory Tagging Extension support" + default y + depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI + select ARCH_USES_HIGH_VMA_FLAGS + help + Memory Tagging (part of the ARMv8.5 Extensions) provides + architectural support for run-time, always-on detection of + various classes of memory error to aid with software debugging + to eliminate vulnerabilities arising from memory-unsafe + languages. + + This option enables the support for the Memory Tagging + Extension at EL0 (i.e. for userspace). + + Selecting this option allows the feature to be detected at + runtime. Any secondary CPU not implementing this feature will + not be allowed a late bring-up. + + Userspace binaries that want to use this feature must + explicitly opt in. The mechanism for the userspace is + described in: + + Documentation/arm64/memory-tagging-extension.rst. + endmenu config ARM64_SVE