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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Jonas Jelonek <jelonek.jonas@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
	linux-mips@vger.kernel.org, Clark Williams <clrkwllms@kernel.org>,
	Steven Rostedt <rostedt@goodmis.org>,
	Thomas Gleixner <tglx@kernel.org>,
	Jiayuan Chen <jiayuan.chen@linux.dev>,
	linux-rt-devel@lists.linux.dev, linux-kernel@vger.kernel.org,
	stable@vger.kernel.org
Subject: Re: [PATCH v2] MIPS: smp: report dying CPU to RCU in stop_this_cpu()
Message-ID: <20260619074323.IIq-0qan@linutronix.de>
References: <20260608093729.12111-1-jelonek.jonas@gmail.com>
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In-Reply-To: <20260608093729.12111-1-jelonek.jonas@gmail.com>

On 2026-06-08 09:37:29 [+0000], Jonas Jelonek wrote:
> smp_send_stop() parks all secondary CPUs in stop_this_cpu(). The function
> marks the CPU offline for the scheduler via set_cpu_online(false) but
> never informs RCU, so RCU keeps expecting a quiescent state from CPUs
> that are now spinning forever with interrupts disabled.
=E2=80=A6
>=20
> Fixes: 91840be8f710 ("irq_work: Fix use-after-free in irq_work_single() o=
n PREEMPT_RT")
> CC: stable@vger.kernel.org
> Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>

Sorry for being late.

Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

Sebastian