Date: Fri, 28 Feb 2014 10:39:40 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Vince Weaver <vincent.weaver@maine.edu>, "H. Peter Anvin" <hpa@zytor.com>,
        Linux Kernel <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@redhat.com>
Subject: Re: perf_fuzzer compiled for x32 causes reboot
Message-ID: <20140228093940.GH27965@twins.programming.kicks-ass.net>
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On Thu, Feb 27, 2014 at 05:31:50PM -0500, Steven Rostedt wrote:
> Well, the perf ring buffer is vmalloced, right? That can cause a page
> fault too.

On x86 they're typically not -- although we have a debug CONFIG option
to test that code on x86 too. On SPARC/ARM etc.. we have to use
vmalloc_user() because of cache aliasing (yay for VIPT).
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