Re: [PATCH] x86: Issue a warning if number of present CPUs > maxcpus and CONFIG_HOTPLUG=n

From: Borislav Petkov
Date: Sun Feb 16 2014 - 12:12:14 EST


On Sat, Feb 15, 2014 at 03:02:23PM +0100, Petr Tesarik wrote:
> Note that the check against i (value passed as maxcpus, but at least 1)
> is repeated further down, including the warning, but since possible is
> already clamped to max_cpus at that time, it is never printed. In fact,
> for the non-hotplug case, the warning about exceeding maxcpus is only
> ever printed if "possible_cpus" was also specified on the command line.
>
> I strongly believe that such limitation was unintentional.
>
> I also changed the message slightly -- the kernel parameter name is
> maxcpus, not max_cpus.
>
> Signed-off-by: Petr Tesarik <ptesarik@xxxxxxx>
> ---
> arch/x86/kernel/smpboot.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
> index a32da80..376b6c6 100644
> --- a/arch/x86/kernel/smpboot.c
> +++ b/arch/x86/kernel/smpboot.c
> @@ -1226,9 +1226,6 @@ __init void prefill_possible_map(void)
> #ifdef CONFIG_HOTPLUG_CPU
> if (setup_max_cpus)
> possible += disabled_cpus;
> -#else
> - if (possible > i)
> - possible = i;

Hmm, ok, this function is not the easiest to parse and provided I'm not
missing some corner case, the cleanup makes sense to me.

Acked-by: Borislav Petkov <bp@xxxxxxx>

--
Regards/Gruss,
Boris.

Sent from a fat crate under my desk. Formatting is fine.
--
--
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/