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Date:   Mon, 21 Mar 2022 12:15:49 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Stephen Rothwell <sfr@canb.auug.org.au>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
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        Linux Next Mailing List <linux-next@vger.kernel.org>,
        mhiramat@kernel.org, ast@kernel.org, hjl.tools@gmail.com,
        rick.p.edgecombe@intel.com, rppt@kernel.org,
        linux-toolchains@vger.kernel.org, Andrew.Cooper3@citrix.com,
        ndesaulniers@google.com
Subject: Re: linux-next: build warnings after merge of the tip tree
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On Mon, 21 Mar 2022 12:12:09 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> > > funcB:
> > > 	call __fentry__    
> > 			push funcB on trace-stack  
> > > 
> > > 	[..]    
> > 	call __fexit__
> > 			pop trace-stack until empty
> > 			  'exit funcB'
> > 			  'exit funcA'  
> 
> And what happens if funcC called funcA and it too was on the stack. We pop
> that too? But it's not done yet, because calling of funcA was not a tail
> call.

And I just thought of another issue, where even my solution wont fix it.
What happens if we trace funcA but not funcB? How do we get to trace the
end of funcA?

-- Steve