Date: Mon, 24 Feb 2014 12:41:14 -0500 (EST)
From: Vince Weaver <vincent.weaver@maine.edu>
To: Vince Weaver <vincent.weaver@maine.edu>
cc: Peter Zijlstra <peterz@infradead.org>, "H. Peter Anvin" <hpa@zytor.com>,
        Linux Kernel <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@redhat.com>, "H.J. Lu" <hjl.tools@gmail.com>,
        Steven Rostedt <rostedt@goodmis.org>
Subject: Re: perf_fuzzer compiled for x32 causes reboot
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On Mon, 24 Feb 2014, Vince Weaver wrote:

> I do note that 
> 	perf_callchain_user();
> 
> Does
> 	fp = (void __user *)regs->bp;
> 	
> 	...
> 
> 	bytes = copy_from_user_nmi(&frame, fp, sizeof(frame));
> 
> 
> And in my particular executable RBP has nothing to do with a frame 
> pointer, but is instead being used as a general purpose register.

and as a reminder, I'm seeing this on an x32 executable, so 
perf_callchain_user32() is probably coming into play.

So maybe it is an x32 issue after all.

Vince
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