Date: Wed, 16 Oct 2013 09:03:25 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Ingo Molnar <mingo@kernel.org>
Cc: LKML <linux-kernel@vger.kernel.org>, Thomas Gleixner <tglx@linutronix.de>,
        "H. Peter Anvin" <hpa@linux.intel.com>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        "paulmck@linux.vnet.ibm.com" <paulmck@linux.vnet.ibm.com>,
        Peter Zijlstra <peterz@infradead.org>,
        "x86@kernel.org" <x86@kernel.org>,
        "Wang, Xiaoming" <xiaoming.wang@intel.com>,
        "Li, Zhuangzhi" <zhuangzhi.li@intel.com>,
        "Liu, Chuansheng" <chuansheng.liu@intel.com>
Subject: Re: [PATCH] x86: Remove WARN_ON(in_nmi()) from vmalloc_fault
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On Wed, 16 Oct 2013 14:51:11 +0200
Ingo Molnar <mingo@kernel.org> wrote:


> So kallsyms_lookup() faulted, while the NMI watchdog triggered a 
> show_regs()? How is that possible?

It was a vmalloc fault. Do modules keep their symbol tables in a
vmalloced area? If so, I think the get_ksymbol() can fault when
searching for a module address.

-- Steve
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