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Date: Wed, 12 Aug 2026 12:21:00 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Karl Mehltretter <kmehltretter@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Andrey Konovalov <andreyknvl@gmail.com>,
	Alexander Potapenko <glider@google.com>,
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	Clark Williams <clrkwllms@kernel.org>,
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Subject: Re: [PATCH v2 3/6] hrtimer: Pause KCOV during deferred rearm
Message-ID: <20260812102100.GF776954@noisy.programming.kicks-ass.net>
References: <20260811154111.64669-1-kmehltretter@gmail.com>
 <20260811154111.64669-4-kmehltretter@gmail.com>
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In-Reply-To: <20260811154111.64669-4-kmehltretter@gmail.com>

On Tue, Aug 11, 2026 at 05:41:08PM +0200, Karl Mehltretter wrote:
> Deferred hrtimer rearm can run after HARDIRQ_OFFSET is dropped. in_task()
> is then true, so KCOV attributes the instrumented timer-reprogramming
> subtree to current.

But that is clearly noinstr code; there should be no kcov calls in
there.

If kcov is emitted inside noinstr, then kcov is a broken piece of crap
and needs to die.

NAK