Re: remove cpu hotplug bustification in cpufreq.

[Dave Jones <davej@redhat.com>]

On Tue, Jul 25, 2006 at 08:54:49PM +0200, Ingo Molnar wrote:
 > 
 > * Linus Torvalds <torvalds@osdl.org> wrote:
 > 
 > > The current -git tree will complain about some of the more obvious 
 > > problems. If you see a "Lukewarm IQ" message, it's a sign of somebody 
 > > re-taking a cpu lock that is already held.
 > testing on my latest-rawhide laptop (kernel-2.6.17-1.2445.fc6 and later 
 > rpms have this change) seems to have pushed the problem over to another 
 > lock:
 > 
 >   S06cpuspeed/1580 is trying to acquire lock:
 >    (&policy->lock){--..}, at: [<c06075f9>] mutex_lock+0x21/0x24
 > 
 >   but task is already holding lock:
 >    (cpu_bitmask_lock){--..}, at: [<c06075f9>] mutex_lock+0x21/0x24
 > 
 >   which lock already depends on the new lock.
 > 
 > and we also get the:
 > 
 >   Lukewarm IQ detected in hotplug locking
 > 
 > message :-| Find the full bootlog below. And i dont understand the 
 > cpufreq code well enough to fix this. In fact, does anyone understand 
 > it? :-/

Things used to be fairly simple until hotplug cpu came along :-/
Each day, I'm getting more of the opinion that my patch just ripping
out this garbage is the right solution.

		Dave

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