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Date: Tue, 17 Jul 2012 15:06:26 -0700
From: Anton Vorontsov <anton.vorontsov@linaro.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Kees Cook <keescook@chromium.org>, Colin Cross <ccross@android.com>,
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Subject: Re: [PATCH 3/8] pstore: Add persistent function tracing
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On Tue, Jul 17, 2012 at 05:38:22PM -0400, Steven Rostedt wrote:
[...]
> > > BTW, can any of the called functions go into module code that can be
> > > removed? If so, then this is not safe at all. Normal function tracing
> > > can not be synced in a preemptible kernel.
> > 
> > Um. Yes, psinfo->write_buf() might be in the module. Nice catch.

Oh, actually, while write_buf() can technically be in a removable module,
the RAM backend can't be removed once loaded. So it is not a real issue.
But I'll implement your idea anyway, it seems a bit cleaner and safer,
plus if we ever want to make persistent_ram backend removable, we won't
need to bother w/ this particular issue.

Thanks!

-- 
Anton Vorontsov
Email: cbouatmailru@gmail.com