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Date:   Wed, 26 Feb 2020 09:15:05 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Andy Lutomirski <luto@kernel.org>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>, 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>
Subject: Re: [patch 5/8] x86/entry/common: Provide trace/kprobe safe exit to
 user space functions
Message-ID: <20200226081505.GP18400@hirez.programming.kicks-ass.net>
References: <20200225220801.571835584@linutronix.de>
 <20200225221305.719921962@linutronix.de>
 <f6f11204-4277-fad0-c1c2-a21e0a380e3b@kernel.org>
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On Tue, Feb 25, 2020 at 09:45:11PM -0800, Andy Lutomirski wrote:
> On 2/25/20 2:08 PM, Thomas Gleixner wrote:
> > Split prepare_enter_to_user_mode() and mark it notrace/noprobe so the irq
> > flags tracing on return can be put into it.
> 
> Is our tooling clever enough for thsi to do anything?  You have a static
> inline that is only called in one place, and the caller is notrace and
> NOKPROBE.  Does this actually allow tracing in the static inline callee?

tracing, no, but the NOKPROBE on inline functions is buggered afaiu.