Messages in this thread Patch in this message | | | From | Alexander Shishkin <> | Subject | [PATCH v3 11/12] x86/cpu: Set LASS CR4 bit as pinning sensitive | Date | Fri, 9 Jun 2023 21:36:31 +0300 |
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From: Yian Chen <yian.chen@intel.com>
Security features such as LASS are not expected to be disabled once initialized. Add LASS to the CR4 pinned mask.
Signed-off-by: Yian Chen <yian.chen@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> --- arch/x86/kernel/cpu/common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index f26c56fe9963..9ddc19c8832d 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -422,7 +422,7 @@ static __always_inline void setup_lass(struct cpuinfo_x86 *c) /* These bits should not change their value after CPU init is finished. */ static const unsigned long cr4_pinned_mask = X86_CR4_SMEP | X86_CR4_SMAP | X86_CR4_UMIP | - X86_CR4_FSGSBASE | X86_CR4_CET; + X86_CR4_FSGSBASE | X86_CR4_CET | X86_CR4_LASS; static DEFINE_STATIC_KEY_FALSE_RO(cr_pinning); static unsigned long cr4_pinned_bits __ro_after_init; -- 2.39.2
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