[PATCHv9 15/16] x86/cpu: Make LAM depend on LASS

Kirill A. Shutemov posted 16 patches 3 months ago
There is a newer version of this series
[PATCHv9 15/16] x86/cpu: Make LAM depend on LASS
Posted by Kirill A. Shutemov 3 months ago
From: Alexander Shishkin <alexander.shishkin@linux.intel.com>

To prevent exploits for Spectre based on LAM as demonstrated by the
whitepaper [1], make LAM depend on LASS, which avoids this type of
vulnerability.

[1] https://download.vusec.net/papers/slam_sp24.pdf

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
---
 arch/x86/kernel/cpu/cpuid-deps.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/kernel/cpu/cpuid-deps.c b/arch/x86/kernel/cpu/cpuid-deps.c
index 98d0cdd82574..11bb9ed40140 100644
--- a/arch/x86/kernel/cpu/cpuid-deps.c
+++ b/arch/x86/kernel/cpu/cpuid-deps.c
@@ -90,6 +90,7 @@ static const struct cpuid_dep cpuid_deps[] = {
 	{ X86_FEATURE_FRED,			X86_FEATURE_LKGS      },
 	{ X86_FEATURE_SPEC_CTRL_SSBD,		X86_FEATURE_SPEC_CTRL },
 	{ X86_FEATURE_LASS,			X86_FEATURE_SMAP      },
+	{ X86_FEATURE_LAM,			X86_FEATURE_LASS      },
 	{}
 };
 
-- 
2.47.2