linux-kernel - nosmp/maxcpus=0 or 1 -> TSC unstable

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Date:	Sat, 12 Jan 2008 11:48:24 -0800 (PST)
From:	dean gaudet <dean@...tic.org>
To:	linux-kernel@...r.kernel.org
Subject: nosmp/maxcpus=0 or 1 -> TSC unstable

if i boot an x86 64-bit 2.6.24-rc7 kernel with nosmp, maxcpus=0 or 1 it 
still disables TSC :)

Marking TSC unstable due to TSCs unsynchronized

this is an opteron 2xx box which does have two cpus and no clock-divide in 
halt or cpufreq enabled so TSC should be fine with only one cpu.

pretty sure this is the culprit is that num_possible_cpus() > 1, which 
would mean cpu_possible_map contains the second cpu... but i'm not quite 
sure what the right fix is... or perhaps this is all intended.

-dean
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