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Manjarres" Cc: matt@codeblueprint.co.uk, mingo@kernel.org, tglx@linutronix.de, bigeasy@linutronix.de, linux-kernel@vger.kernel.org, psodagud@codeaurora.org, gregkh@linuxfoundation.org, pkondeti@codeaurora.org, stable@vger.kernel.org Subject: Re: [PATCH v4] stop_machine: Disable preemption after queueing stopper threads Message-ID: <20180717183450.GL2494@hirez.programming.kicks-ass.net> References: <1531845017-19935-1-git-send-email-isaacm@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1531845017-19935-1-git-send-email-isaacm@codeaurora.org> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 17, 2018 at 09:30:17AM -0700, Isaac J. Manjarres wrote: > After cpu_stop_queue_two_works() queues the cpu_stop works > for the stopper threads, it releases the locks held for > both threads, which enables preemption, which allows the > following race condition to occur: Does not apply because an earlier version is already applied. https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/kernel/stop_machine.c?id=9fb8d5dc4b649dd190e1af4ead670753e71bf907 if there still is a problem, please send a new patch that describes the remaining problem.