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Date: Wed, 23 Oct 2024 20:40:01 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Jordan Rife <jrife@google.com>, acme@kernel.org,
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Subject: Re: [RFC PATCH] tracing: Fix syscall tracepoint use-after-free
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On Wed, 23 Oct 2024 11:13:53 -0400
Mathieu Desnoyers <mathieu.desnoyers@efficios.com> wrote:

> That question is relevant for ftrace and perf too: are there data
> structures that are reclaimed with call_rcu() after being unregistered
> from syscall tracepoints ?

ftrace doesn't assume RCU for when to synchronize with tracepoints
being unregistered. It uses:

  tracepoint_synchronize_unregister()

-- Steve