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McKenney" Cc: "Uladzislau Rezki (Sony)" , "Paul E . McKenney" , Boqun Feng , Joel Fernandes , RCU , LKML , Vasily Gorbik , Frederic Weisbecker , Samir , Shrikanth Hegde , Tejun Heo , Linux kernel regressions list Subject: Re: [PATCH -next v1 05/12] srcu: Don't queue workqueue handlers to never-online CPUs Message-ID: References: <20260511175448.153326-1-urezki@gmail.com> <20260511175448.153326-6-urezki@gmail.com> Precedence: bulk X-Mailing-List: rcu@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: On Wed, May 13, 2026 at 12:38:01PM +0200, Thorsten Leemhuis wrote: > On 5/11/26 19:54, Uladzislau Rezki (Sony) wrote: > > From: "Paul E. McKenney" > > > > While an srcu_struct structure is in the midst of switching from CPU-0 > > to all-CPUs state, it can attempt to invoke callbacks for CPUs that > > have never been online. Worse yet, it can attempt in invoke callbacks > > for CPUs that never will be online, even including imaginary CPUs not in > > cpu_possible_mask. This can cause hangs on s390, > > Uladzislau, Paul, according to the fixes tag below this change fixes a > change that went into 7.0-rc6 -- and apparently causes a "hang" on some > architectures. So shouldn't this be heading to mainline instead of > -next? Ideally with a stable tag to ensure backporting to 7.0.y, but > that is a separate decision? > I assume it will be picked to stable since there is a "Fixes:" tag. From the other hand i can explicitly update commit message with Cc: stable@vger.kernel.org Paul, any thoughts? -- Uladzislau Rezki