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Thu, 10 Sep 2026 00:21:35 -0700 (PDT) Date: Thu, 10 Sep 2026 09:21:32 +0200 From: Andrea Parri To: Thomas Gleixner Cc: Anna-Maria Behnsen , Frederic Weisbecker , Peter Zijlstra , linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH v2] hrtimer: Use hard expiry when updating timers on the same base Message-ID: References: <20260909102749.7677-1-parri.andrea@gmail.com> <87v78eza1x.ffs@fw13> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87v78eza1x.ffs@fw13> > So this really wants to have a big fat comment explaining why this is > safe to do. Agreed. The existing comment only describes the update and misses the temporary tree inconsistency. I'll spell out that the base lock excludes other queue operations, that the neighbour check proves the node can remain in place, and that removal does not consult the expiry otherwise. Thanks, Andrea