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Date:   Tue, 12 Dec 2023 14:46:58 +0100
From:   Frederic Weisbecker <frederic@kernel.org>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     linux-kernel@vger.kernel.org,
        Andrew Cooper <Andrew.Cooper3@citrix.com>,
        linux-tip-commits@vger.kernel.org,
        "Rafael J. Wysocki" <rafael@kernel.org>, x86@kernel.org
Subject: Re: [tip: x86/core] x86: Fix CPUIDLE_FLAG_IRQ_ENABLE leaking timer
 reprogram
Message-ID: <ZXhkUshO49ldjBio@lothringen>
References: <20231115151325.6262-3-frederic@kernel.org>
 <170126975511.398.12493947150541739641.tip-bot2@tip-bot2>
 <20231130111519.GA20153@noisy.programming.kicks-ass.net>
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On Thu, Nov 30, 2023 at 12:15:19PM +0100, Peter Zijlstra wrote:
> This is so, because all mwait users should be in __cpuidle section,
> which itself is part of the noinstr section and as such
> kprobes/hw-breakpoints etc.. are disallowed.
> 
> Notable vmlinux.lds.h has:
> 
> #define NOINSTR_TEXT							\
> 		ALIGN_FUNCTION();					\
> 		__noinstr_text_start = .;				\
> 		*(.noinstr.text)					\
> 		__cpuidle_text_start = .;				\
> 		*(.cpuidle.text)					\
> 		__cpuidle_text_end = .;					\
> 		__noinstr_text_end = .;

So #DB aren't supposed to happen then, right? Or you noticed an mwait
user that doesn't have __cpuidle?

Thanks.