In particular if we're running virtualized, the underlying hypervisor (which may be another Xen) may not surface MTRRs, and offer PAT only.
Fixes: 5a281883cdc3 ("Hardcode many cpu features for x86/64 -- we know 64-bit") Signed-off-by: Jan Beulich <jbeul...@suse.com> --- a/xen/arch/x86/include/asm/cpufeature.h +++ b/xen/arch/x86/include/asm/cpufeature.h @@ -70,7 +70,7 @@ static inline bool boot_cpu_has(unsigned #define cpu_has_pse 1 #define cpu_has_apic boot_cpu_has(X86_FEATURE_APIC) #define cpu_has_sep boot_cpu_has(X86_FEATURE_SEP) -#define cpu_has_mtrr 1 +#define cpu_has_mtrr boot_cpu_has(X86_FEATURE_MTRR) #define cpu_has_pge 1 #define cpu_has_pse36 boot_cpu_has(X86_FEATURE_PSE36) #define cpu_has_clflush boot_cpu_has(X86_FEATURE_CLFLUSH)