I own a Intel Pentium 4 processor calles "506+". There's a mismatch of information, some vendors distribute this as ht-compatible, but Intel website states that this processor is not ht compatible. However, /proc/cpuinfo has the flag "ht" enabled but I cannot get HT to work. It's enabled in the BIOS and ACPI is also enabled and working. So this processor seems not to support HT (this is consistent with Intel website and the product package). So the linux kernel should also not tell me a ht capability. /proc/cpuinfo says: processor : 0 vendor_id : GenuineIntel cpu family : 15 model : 4 model name : Intel(R) Pentium(R) 4 CPU 2.66GHz stepping : 9 cpu MHz : 2666.600 cache size : 1024 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 5 wp : yes 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 nx lm constant_tsc up pni monitor ds_cpl tm2 cid cx16 xtpr bogomips : 5310.85 clflush size : 64
This is not a bug: "ht" means there can be multiple CPUs per core. Whether they are physical or logical doesn't matter.