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Date:   Mon, 15 Jun 2020 16:35:23 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Marco Elver <elver@google.com>
Cc:     Dmitry Vyukov <dvyukov@google.com>,
        Andrey Konovalov <andreyknvl@google.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Borislav Petkov <bp@alien8.de>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@kernel.org>,
        clang-built-linux <clang-built-linux@googlegroups.com>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Alexander Potapenko <glider@google.com>,
        kasan-dev <kasan-dev@googlegroups.com>,
        LKML <linux-kernel@vger.kernel.org>,
        the arch/x86 maintainers <x86@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>
Subject: Re: [PATCH -tip v3 1/2] kcov: Make runtime functions
 noinstr-compatible
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On Mon, Jun 15, 2020 at 04:29:50PM +0200, Peter Zijlstra wrote:
> Let me go look at your KCSAN thing now...

vmlinux.o: warning: objtool: idtentry_enter_cond_rcu()+0x16: call to is_idle_task() leaves .noinstr.text section

---
diff --git a/include/linux/sched.h b/include/linux/sched.h
index b62e6aaf28f03..a7abc18a7d0ad 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1663,7 +1663,7 @@ extern struct task_struct *idle_task(int cpu);
  *
  * Return: 1 if @p is an idle task. 0 otherwise.
  */
-static inline bool is_idle_task(const struct task_struct *p)
+static __always_inline bool is_idle_task(const struct task_struct *p)
 {
 	return !!(p->flags & PF_IDLE);
 }