On 02/18/13 17:48, David Woodhouse wrote: > On Mon, 2013-02-18 at 16:38 +0100, Paolo Bonzini wrote: >> Indeed the difference between CPUs is puzzling. > > Very much so. So far I have established that it works OK here: > > cpu family : 6 > model : 44 > model name : Intel(R) Core(TM) i7 CPU X 980 @ 3.33GHz > stepping : 2 > microcode : 0x5 > flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov > pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx > pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl > xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx > est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 popcnt aes lahf_lm arat > dtherm tpr_shadow vnmi flexpriority ept vpid
> ... but not here: > > cpu family : 6 > model : 30 > model name : Intel(R) Core(TM) i7 CPU 870 @ 2.93GHz > stepping : 5 > microcode : 0x5 > flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov > pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx > rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology > nonstop_tsc aperfmperf pni dtes64 monitor ds_cpl vmx smx est tm2 ssse3 > cx16 xtpr pdcm sse4_1 sse4_2 popcnt lahf_lm ida dtherm tpr_shadow vnmi > flexpriority ept vpid Maybe related to <https://patchwork.kernel.org/patch/26836/>? Anyway, the X980 seems to have these in addition to the shared flags: #define X86_FEATURE_AES (4*32+25) /* AES instructions */ #define X86_FEATURE_ARAT (7*32+ 1) /* Always Running APIC Timer */ #define X86_FEATURE_PCID (4*32+17) /* Process Context Identifiers */ #define X86_FEATURE_PCLMULQDQ (4*32+ 1) /* PCLMULQDQ instruction */ #define X86_FEATURE_GBPAGES (1*32+26) /* "pdpe1gb" GB pages */ Unique to the 870 is: #define X86_FEATURE_IDA (7*32+ 0) /* Intel Dynamic Acceleration */ #define X86_FEATURE_SMX (4*32+ 6) /* Safer mode */ Laszlo
