From: Mark Brown Date: Tue, 13 Feb 2024 15:32:45 +0000 (+0000) Subject: arm64/sve: Ensure that all fields in ZCR_EL1 are set to known values X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=2f0090549b649cc9fd61c0193189c25f8fc03119;p=linux.git arm64/sve: Ensure that all fields in ZCR_EL1 are set to known values At present nothing in our CPU initialisation code ever sets unknown fields in ZCR_EL1 to known values, all updates to ZCR_EL1 are read/modify/write sequences for LEN. All the unknown fields are RES0, explicitly initialise them as such to avoid future surprises. Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20240213-arm64-fp-init-vec-cr-v1-1-7e7c2d584f26@kernel.org Signed-off-by: Catalin Marinas --- diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index a5dc6f7641958..cc3c9ad877a8c 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -1134,6 +1134,8 @@ void cpu_enable_sve(const struct arm64_cpu_capabilities *__always_unused p) { write_sysreg(read_sysreg(CPACR_EL1) | CPACR_EL1_ZEN_EL1EN, CPACR_EL1); isb(); + + write_sysreg_s(0, SYS_ZCR_EL1); } void __init sve_setup(void)