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Subject: Re: [patch 6/8] x86/entry: Move irq tracing to syscall_slow_exit_work
To:     Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>
Cc:     x86@kernel.org, Steven Rostedt <rostedt@goodmis.org>,
        Brian Gerst <brgerst@gmail.com>,
        Juergen Gross <jgross@suse.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Arnd Bergmann <arnd@arndb.de>
References: <20200225220801.571835584@linutronix.de>
 <20200225221305.813084267@linutronix.de>
From:   Andy Lutomirski <luto@kernel.org>
Message-ID: <e6951061-a397-21e5-3bb7-72de97d37d49@kernel.org>
Date:   Tue, 25 Feb 2020 21:47:52 -0800
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On 2/25/20 2:08 PM, Thomas Gleixner wrote:
> which removes the ASM IRQ tracepoints.

It's still after we re-enter rcuidle.  Is tracing actually okay?

I always had the impression that tracing was okay in rcuidle mode
because the tracing code was smart enough to do the right thing, but
your patch 3/8 changelog says:

Anything before enter_from_user_mode() is not safe to be traced or probed.


--Andy