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Date: Mon, 03 Mar 2014 14:27:09 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Steven Rostedt <rostedt@goodmis.org>
CC: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Petr Mladek <pmladek@suse.cz>, stable@vger.kernel.org
Subject: Re: [RFA][PATCH 1/5] ftrace/x86: Run a sync after fixup on failure
References: <20140227154616.703252665@goodmis.org>	<20140227154922.957070805@goodmis.org>	<5314FE46.3060003@zytor.com> <20140303171816.176ca337@gandalf.local.home>
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On 03/03/2014 02:18 PM, Steven Rostedt wrote:
> 
> How's this sound:
> 
> The second bug was that the removal of the breakpoints required the
> "within()" logic updates instead of accessing the ip address directly.
> As kernel text is mapped read-only when CONFIG_DEBUG_RODATA is set, and
> the removal of the breakpoint is a modification of kernel text.
> 

I'd add:

"ftrace_write() includes this, but probe_kernel_write() does not."

	-hpa