Re: latest -git: WARNING: at arch/x86/kernel/ipi.c:123 send_IPI_mask_bitmask+0xc3/0xe0()

Vegard Nossum
2008-08-24T09:21:06Z

On Fri, Aug 22, 2008 at 4:13 AM, H. Peter Anvin <hpa@kernel.org> wrote:
> It seems to be that doing it in smp_call_function_single() would be more
> correct as it's already protected by get_cpu()..put_cpu() and a cpu_online()
> test in there should not be expensive in comparison to the whole rest of the
> code.
>
> You may want to see if this patch fixes the problem; it does *NOT* have the
> correct error behaviour (some of the intervening layers don't propagate
> errors), but it should make the fault go away.

Hm.

Kernel fails to detect cpu1 at all.

I am currently unsure of whether it's your patch or not. But it's the
same config that I've been booting for ages (and I copy it over for
each new kernel version I check out).

Processor #0 (Bootup-CPU)
I/O APIC #2 Version 32 at 0xFEC00000.
Enabling APIC mode: Flat. Using 1 I/O APICs
Processors: 1
SMP: Allowing 1 CPUs, 0 hotplug CPUs
mapped APIC to ffffb000 (fee00000)
mapped IOAPIC to ffffa000 (fec00000)
Allocating PCI resources starting at 50000000 (gap: 40000000:bee00000)
PERCPU: Allocating 1221764 bytes of per cpu data
NR_CPUS: 7, nr_cpu_ids: 1, nr_node_ids 1

I really don't get it. Is this something that can be caused by your
patch _at all_ ?

Vegard

--
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
-- E. W. Dijkstra, EWD1036