From a46cec12f4a53ee5113f42b327cbb8d4cda074d2 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Fri, 24 Jul 2020 10:41:31 +0100 Subject: arm64: Reserve HWCAP2_MTE as (1 << 18) While MTE is not supported in the upstream kernel yet, add a comment that HWCAP2_MTE as (1 << 18) is reserved. Glibc makes use of it for the resolving (ifunc) of the MTE-safe string routines. Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/hwcap.h | 1 + arch/arm64/include/uapi/asm/hwcap.h | 1 + arch/arm64/kernel/cpuinfo.c | 1 + 3 files changed, 3 insertions(+) diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h index d683bcbf1e7c..22f73fe09030 100644 --- a/arch/arm64/include/asm/hwcap.h +++ b/arch/arm64/include/asm/hwcap.h @@ -95,6 +95,7 @@ #define KERNEL_HWCAP_DGH __khwcap2_feature(DGH) #define KERNEL_HWCAP_RNG __khwcap2_feature(RNG) #define KERNEL_HWCAP_BTI __khwcap2_feature(BTI) +/* reserved for KERNEL_HWCAP_MTE __khwcap2_feature(MTE) */ /* * This yields a mask that user programs can use to figure out what diff --git a/arch/arm64/include/uapi/asm/hwcap.h b/arch/arm64/include/uapi/asm/hwcap.h index 2d6ba1c2592e..912162f73529 100644 --- a/arch/arm64/include/uapi/asm/hwcap.h +++ b/arch/arm64/include/uapi/asm/hwcap.h @@ -74,5 +74,6 @@ #define HWCAP2_DGH (1 << 15) #define HWCAP2_RNG (1 << 16) #define HWCAP2_BTI (1 << 17) +/* reserved for HWCAP2_MTE (1 << 18) */ #endif /* _UAPI__ASM_HWCAP_H */ diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c index 86637466daa8..393c6fb1f1cb 100644 --- a/arch/arm64/kernel/cpuinfo.c +++ b/arch/arm64/kernel/cpuinfo.c @@ -93,6 +93,7 @@ static const char *const hwcap_str[] = { "dgh", "rng", "bti", + /* reserved for "mte" */ NULL }; -- cgit v1.2.3