Date: Mon, 14 Feb 2011 13:46:00 -0800 (PST)
Message-Id: <20110214.134600.179933733.davem@davemloft.net>
To: rostedt@goodmis.org
Cc: peterz@infradead.org, will.newton@gmail.com, jbaron@redhat.com,
        mathieu.desnoyers@polymtl.ca, hpa@zytor.com, mingo@elte.hu,
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Subject: Re: [PATCH 0/2] jump label: 2.6.38 updates
From: David Miller <davem@davemloft.net>
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From: Steven Rostedt <rostedt@goodmis.org>
Date: Mon, 14 Feb 2011 16:39:36 -0500

> Thus it is not about global, as global is updated by normal means and
> will update the caches. atomic_t is updated via the ll/sc that ignores
> the cache and causes all this to break down. IOW... broken hardware ;)

I don't see how cache coherency can possibly work if the hardware
behaves this way.

In cache aliasing situations, yes I can understand a L1 cache visibility
issue being present, but with kernel only stuff that should never happen
otherwise we have a bug in the arch cache flushing support.
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