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Date: Tue, 2 Sep 2014 11:00:12 -0500 (CDT)
From: Christoph Lameter <cl@linux.com>
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To: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
cc: Fengguang Wu <fengguang.wu@intel.com>, Jet Chen <jet.chen@intel.com>,
        Su Tao <tao.su@intel.com>, Yuanhan Liu <yuanhan.liu@intel.com>,
        LKP <lkp@01.org>, linux-kernel@vger.kernel.org
Subject: Re: [percpu] BUG: unable to handle kernel NULL pointer dereference
 at (null)
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References: <20140902045830.GA11321@localhost> <20140902153403.GY5001@linux.vnet.ibm.com>
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On Tue, 2 Sep 2014, Paul E. McKenney wrote:

> Before this commit, raw_cpu_add_return() didn't build.  The commit
> didn't affect anything else.
>
> So I don't understand how anything could work before this commit and
> be broken after it.  Enlightenment?

Where is that raw_cpu_add_return statement?

grep does not match anything like that in kernel/rcu/*
and this_cpu_add_return is used extensively in the network subsystem for
statistics.

From mboxrd@z Thu Jan  1 00:00:00 1970
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From: Christoph Lameter <cl@linux.com>
To: lkp@lists.01.org
Subject: Re: [percpu] BUG: unable to handle kernel NULL pointer dereference at (null)
Date: Tue, 02 Sep 2014 11:00:12 -0500
Message-ID: <alpine.DEB.2.11.1409021052400.10607@gentwo.org>
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On Tue, 2 Sep 2014, Paul E. McKenney wrote:

> Before this commit, raw_cpu_add_return() didn't build.  The commit
> didn't affect anything else.
>
> So I don't understand how anything could work before this commit and
> be broken after it.  Enlightenment?

Where is that raw_cpu_add_return statement?

grep does not match anything like that in kernel/rcu/*
and this_cpu_add_return is used extensively in the network subsystem for
statistics.

--===============3855701084609417990==--