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Date: Thu, 19 Jun 2025 09:51:03 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
	bpf@vger.kernel.org, x86@kernel.org,
	Masami Hiramatsu <mhiramat@kernel.org>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
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	Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH v10 03/14] unwind_user: Add compat mode frame pointer
 support
Message-ID: <20250619075103.GV1613376@noisy.programming.kicks-ass.net>
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On Wed, Jun 18, 2025 at 11:18:40AM -0400, Steven Rostedt wrote:
> On Wed, 18 Jun 2025 15:47:58 +0200
> Peter Zijlstra <peterz@infradead.org> wrote:
> 
> > On Tue, Jun 10, 2025 at 08:54:24PM -0400, Steven Rostedt wrote:
> > 
> > > +#ifndef arch_unwind_user_init
> > > +static inline void arch_unwind_user_init(struct unwind_user_state *state, struct pt_regs *reg) {}
> > > +#endif
> > > +
> > > +#ifndef arch_unwind_user_next
> > > +static inline void arch_unwind_user_next(struct unwind_user_state *state) {}
> > > +#endif  
> > 
> > The purpose of these arch hooks is so far mysterious. No comments, no
> > changelog, no nothing.
> 
> I'll add comments.

How about you introduce the hooks when they're actually needed instead?