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Date: Tue, 3 Feb 2026 12:44:54 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Lyude Paul <lyude@redhat.com>
Cc: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org,
	Thomas Gleixner <tglx@linutronix.de>,
	Boqun Feng <boqun.feng@gmail.com>,
	Daniel Almeida <daniel.almeida@collabora.com>,
	Miguel Ojeda <ojeda@kernel.org>,
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	=?iso-8859-1?Q?Bj=F6rn?= Roy Baron <bjorn3_gh@protonmail.com>,
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	Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>,
	Waiman Long <longman@redhat.com>,
	Joel Fernandes <joelagnelf@nvidia.com>
Subject: Re: [PATCH v17 02/16] preempt: Track NMI nesting to separate per-CPU
 counter
Message-ID: <20260203114454.GM1282955@noisy.programming.kicks-ass.net>
References: <20260121223933.1568682-1-lyude@redhat.com>
 <20260121223933.1568682-3-lyude@redhat.com>
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In-Reply-To: <20260121223933.1568682-3-lyude@redhat.com>

On Wed, Jan 21, 2026 at 05:39:05PM -0500, Lyude Paul wrote:

> diff --git a/kernel/softirq.c b/kernel/softirq.c
> index 77198911b8dd4..af47ea23aba3b 100644
> --- a/kernel/softirq.c
> +++ b/kernel/softirq.c
> @@ -88,6 +88,8 @@ EXPORT_PER_CPU_SYMBOL_GPL(hardirqs_enabled);
>  EXPORT_PER_CPU_SYMBOL_GPL(hardirq_context);
>  #endif
>  
> +DEFINE_PER_CPU(unsigned int, nmi_nesting);

What happened with putting this in the same line as preempt_count?