Yinghai Lu <[EMAIL PROTECTED]> writes: > quad core 8 socket system will have apic id lifting.the apic id range could > be [4, 0x23]. or [8, 0x27]. apic_is_clustered_box will think that need to > three clusters > and that is large than 2. So it is treated as clustered_box. > > and will get > > Marking TSC unstable due to TSCs unsynchronized > > even the CPUs have X86_FEATURE_CONSTANT_TSC set. > > this patch offset back the apic before get apic clusterid. > > or use dmi to get apic_is_clustered?
The clustered check is for Summit and es7000 systems On 64bit systems it might be actually possible to trigger this based on SLIT instead. But you'll need to check with the IBM Summit/Unisys es7000 developers if that works or not If you don't want to do that the safer way would be probably the check if there are holes between the CPUs APIC numbers. If yes then it's likely clustered mode. I think that would be better than to disable it unconditionally for apic lifting like your patches does. -Andi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/