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Tue, 29 Sep 2026 23:26:47 -0700 (PDT) From: Liang Hao To: tglx@kernel.org Cc: anna-maria@linutronix.de, frederic@kernel.org, haohlliang@gmail.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] timers: Clear pending_map on CPU hotplug Date: Wed, 30 Sep 2026 14:26:42 +0800 Message-ID: <20260930062642.36164-1-haohlliang@gmail.com> X-Mailer: git-send-email 2.54.0 In-Reply-To: <87bj9fizww.ffs@fw13> References: <87bj9fizww.ffs@fw13> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Tue, 29 Sep 2026 at 22:08, Thomas Gleixner wrote: > Why do you need to zero the map twice - once when the CPU goes out and > then again when it comes back. That does not make sense. You're right - clearing it twice is redundant. The stale bits come from migration in timers_dead_cpu(); clearing pending_map there after migration is sufficient. I'll remove the timers_prepare_cpu() part in v2. Thanks, Liang Hao