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Date:   Sat, 29 Feb 2020 18:58:37 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Andy Lutomirski <luto@amacapital.net>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, x86@kernel.org,
        Brian Gerst <brgerst@gmail.com>,
        Juergen Gross <JGross@suse.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Arnd Bergmann <arnd@arndb.de>,
        "Paul E. McKenney" <paulmck@kernel.org>
Subject: Re: [patch 4/8] x86/entry: Move irq tracing on syscall entry to
 C-code
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On Sat, 29 Feb 2020 11:25:24 -0800
Andy Lutomirski <luto@amacapital.net> wrote:

> > While the tracer itself seems to handle this correctly, what about
> > things like BPF programs which can be attached to tracepoints and
> > function trace entries?  
> 
> I think that everything using the tracing code, including BPF, should
> either do its own rcuidle stuff or explicitly not execute if we’re
> not in CONTEXT_KERNEL.  That is, we probably need to patch BPF.

That's basically the route we are taking.

-- Steve