LASS (Linear-address space separation) is an independent mechanism to enforce the mode-based protection that can prevent user-mode accesses to supervisor-mode addresses, and vice versa. Because the LASS protections are applied before paging, malicious software can not acquire any paging-based timing information to compromise the security of system. The CPUID bit definition to support LASS: CPUID.(EAX=07H.ECX=1):EAX.LASS[bit 6] Advertise LASS to user space to support LASS virtualization. Signed-off-by: Zeng Guang <guang.zeng@xxxxxxxxx> Tested-by: Xuelian Guo <xuelian.guo@xxxxxxxxx> --- arch/x86/kvm/cpuid.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 0c9660a07b23..a7fafe99ffe4 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -646,9 +646,8 @@ void kvm_set_cpu_caps(void) kvm_cpu_cap_set(X86_FEATURE_SPEC_CTRL_SSBD); kvm_cpu_cap_mask(CPUID_7_1_EAX, - F(AVX_VNNI) | F(AVX512_BF16) | F(CMPCCXADD) | - F(FZRM) | F(FSRS) | F(FSRC) | - F(AMX_FP16) | F(AVX_IFMA) + F(AVX_VNNI) | F(AVX512_BF16) | F(LASS) | F(CMPCCXADD) | + F(FZRM) | F(FSRS) | F(FSRC) | F(AMX_FP16) | F(AVX_IFMA) ); kvm_cpu_cap_init_kvm_defined(CPUID_7_1_EDX, -- 2.27.0
