Date: Thu, 12 May 2011 14:37:41 -0400
From: Dave Jones <davej@redhat.com>
To: David Miller <davem@davemloft.net>
Cc: eranian@google.com, acme@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [BUG] perf: bogus correlation of kernel symbols
Message-ID: <20110512183741.GA22269@redhat.com>
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	David Miller <davem@davemloft.net>, eranian@google.com,
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On Thu, May 12, 2011 at 02:06:30PM -0400, David Miller wrote:
 > From: Stephane Eranian <eranian@google.com>
 > Date: Thu, 12 May 2011 16:48:46 +0200
 > 
 > > I think there is a serious problem with kernel symbol correlation
 > > with the latest perf in 2.6.39-rc7-tip.
 > 
 > The behavior seems to be intentional, so that we don't expose internal
 > kernel addresses to userspace.

Sounds like commit 9f36e2c448007b54851e7e4fa48da97d1477a175

 > I hate this too, and I think it's absolutely rediculous.
 > 
 > Also, like you, I lost an entire afternoon trying to figure out why
 > this started happening.
 > 
 > I wish we could revert this change.

At least it can be permanently disabled..

echo kernel.kptr_restrict = 0 >> /etc/sysctl.conf

	Dave

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