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Date: Wed, 5 Aug 2026 15:34:04 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>, Ingo Molnar
 <mingo@kernel.org>, x86@kernel.org, Jinchao Wang
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 linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
 linux-doc@vger.kernel.org, linux-perf-users@vger.kernel.org
Subject: Re: [PATCH v11 04/11] tracing: wprobe: Add watchpoint probe event
 based on hardware breakpoint
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On Mon, 3 Aug 2026 09:03:56 +0200
Peter Zijlstra <peterz@infradead.org> wrote:

> > The new syntax is;
> > 
> >  w[:[GROUP/]EVENT] [r|w|rw]@[ADDR|SYM][:SIZE] [FETCH_ARGs]
> > 
> > User also can use $addr to fetch the accessed address and $value to fetch
> > the accessed memory value (shorthand for '+0($addr)'). No other variables
> > are supported.  
> 
> This seems limited to kernel addresses only? Should not also userspace
> addresses be supported?

Hmm, how would that work? The address is global for all tasks, so if you
add a user space address, what task would that be for? The one writing the
probe?

-- Steve