Re: [Suggestion] about calling debug_hotplug_cpu() which enabled by'allmodconfig' for a x86_64 dual core laptop.

[Toshi Kani]

On Wed, 2013-10-02 at 03:10 +0000, Chen Gang wrote:
> Hello Maintainers:
> 
> Under my x86_64 dual core laptop, I build kernel next-20130927 with
> 'allmodconfig', and install it, the machine can not start. Related
> information is:
> 
>   after call debug_hotplug_cpu(), output "cpu 0 is offline" .... and then "Failed to execute /init".
> 
> After remove "_debug_hotplug_cpu(0, 0);", can pass the issue (but will
> fail in another place). I guess, the reason is my laptop cpu is not
> 'hotplug', but have to call debug_hotplug_cpu() with allmodconfig.
> 
> 
> I will continue analyzing, welcome any additional suggestions or
> completions.

allmodconfig sets CONFIG_DEBUG_HOTPLUG_CPU0 to y (which is defined as
"def_bool n"), which puts CPU0 offline during boot for testing.  This
debug feature is causing the problem on your laptop.  I am not familiar
with allmodconfig, but it seems that it enables all the config options,
preferably with 'm'.

Thanks,
-Toshi

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/