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Date: Wed, 28 Feb 2024 19:14:06 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>, x86@kernel.org,
 linux-kernel@vger.kernel.org, Peter Zijlstra <peterz@infradead.org>, Vince
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 <jannh@google.com>, Miroslav Benes <mbenes@suse.cz>, Andy Lutomirski
 <luto@kernel.org>, Thomas Gleixner <tglx@linutronix.de>, Masami Hiramatsu
 <mhiramat@kernel.org>, Nilay Vaish <nilayvaish@google.com>
Subject: Re: [PATCH v2 06/11] x86/unwind/orc: Convert global variables to
 static
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On Wed, 28 Feb 2024 16:03:09 -0800
Josh Poimboeuf <jpoimboe@kernel.org> wrote:

> On Wed, Feb 28, 2024 at 06:35:07PM -0500, Steven Rostedt wrote:
> > On Sat, 25 Apr 2020 05:03:05 -0500
> > Josh Poimboeuf <jpoimboe@redhat.com> wrote:
> >   
> > > These variables aren't used outside of unwind_orc.c, make them static.
> > > 
> > > Also annotate some of them with '__ro_after_init', as applicable.  
> > 
> > So it appears that crash uses "lookup_num_blocks" to be able to do
> > back-traces with the ORC unwinder. But because it's now static, crash can no
> > longer do that.  
> 
> Hm, but why?  Even a static variable has a known address.
> 

I'm guessing because we don't have the full dwarf info?

-- Steve