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From: Rusty Russell <rusty@rustcorp.com.au>
To: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: x86@kernel.org, LKML <linux-kernel@vger.kernel.org>,
        Paul McKenney <paul.mckenney@us.ibm.com>
Subject: Re: [PATCH] x86: don't ever patch back to UP if we unplug cpus.
In-Reply-To: <1343420909.3696.560.camel@sbsiddha-desk.sc.intel.com>
References: <87y5m5mz6o.fsf@rustcorp.com.au> <1343420909.3696.560.camel@sbsiddha-desk.sc.intel.com>
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Date: Mon, 30 Jul 2012 11:38:57 +0930
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On Fri, 27 Jul 2012 13:28:29 -0700, Suresh Siddha <suresh.b.siddha@intel.com> wrote:
> 	if (!noreplace_smp && (num_present_cpus() == 1 || setup_max_cpus <= 1))
> 
> also, to be consistent with other checks, may be just use
> "num_possible_cpus() == 1" check instead of "setup_max_cpus <= 1".

Actually, if you specify "maxcpus=1" on the kernel command line,
you get num_possible_cpus() == 4, even though only one gets online.

So the setup_max_cpus check is in fact correct here.

Thanks!
Rusty.