Messages in this thread | | | Date | Sat, 24 Mar 2007 20:11:12 +0100 | From | Ingo Molnar <> | Subject | Re: [PATCH] x86_64: avoid sending LOCAL_TIMER_VECTOR IPI to itself |
| |
* Ray Lee <ray-lk@madrabbit.org> wrote:
> Subject: [PATCH] x86_64: avoid sending LOCAL_TIMER_VECTOR IPI to > itself > > Ray Lee reported, that on an UP kernel with "noapic" command line > option set, the box locks hard during boot.
i think this bug deserves a bit more attention, because similar problems could be in other codepaths too.
the problem here is that we tried to send an IPI to ourselves - which confused Ray's system which has an IO-APIC, but where due to noapic we keep the IO-APIC in its BIOS default.
this isnt a new problem: the new time code just exposed it more prominently that it was visible before. (the SMP kernel probably would hang in a similar way on Ray's system)
i dont see any clear debugging in the IPI code that excludes self-IPIs. I think the only valid way to do that is to use DEST_SELF. Andi?
Ingo - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |