Re: [PATCH] tracing: Export key trace event symbols

From: Steven Rostedt <rostedt@goodmis.org>
To: Ron Rechenmacher <ron@fnal.gov>
Cc: Christoph Hellwig <hch@infradead.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] tracing: Export key trace event symbols
Date: Tue, 21 Apr 2015 09:53:10 -0400	[thread overview]
Message-ID: <20150421095310.12370f88@gandalf.local.home> (raw)
In-Reply-To: <55365002.4010707@fnal.gov>

On Tue, 21 Apr 2015 08:26:26 -0500
Ron Rechenmacher <ron@fnal.gov> wrote:

> But why export anything _GPL in the first place?
> 

To make it clear that they are derivatives of the kernel. An export is
just to allow modules access to the functions, they were not added for
out of tree modules. Out of tree modules just happen to be lucky to
have them available.

Note, if you can present a good case to why they should be exported,
then we should have no problem exporting them. But I just looked at
your code, and I have some questions about it.

EXPORT_SYMBOL( traceControl_p );
EXPORT_SYMBOL( traceEntries_p );
EXPORT_SYMBOL( traceNamLvls_p );
EXPORT_SYMBOL( trace_allow_printk );

You have non GPL exported functions. Why? Is this used by non GPL code?

MODULE_LICENSE("GPL"); /* Get rid of taint message by declaring code as GPL */

That comment is very telling.

Maybe I'm reading into things, but until we understand exactly why you
need these symbols exported, we wont exported them. There's no kernel
ABI that we must stick to. Only the user space ABI is what we keep
stable.

-- Steve