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Donenfeld" Cc: linux-kernel@vger.kernel.org, mingo@redhat.com, ebiederm@xmission.com, Toke =?iso-8859-1?Q?H=F8iland-J=F8rgensen?= , Kalle Valo , Johannes Berg Subject: Re: [PATCH] signal: break out of wait loops on kthread_stop() Message-ID: References: <20220627120020.608117-1-Jason@zx2c4.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220627120020.608117-1-Jason@zx2c4.com> X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED,SPF_HELO_NONE, SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 27, 2022 at 02:00:20PM +0200, Jason A. Donenfeld wrote: > +bool __kthread_should_stop(struct task_struct *k) > +{ > + return (k->flags & PF_KTHREAD) && > + test_bit(KTHREAD_SHOULD_STOP, &to_kthread(k)->flags); > +} This used to be a racy pattern; not sure it still is since Eric poked at this last, but please use __to_kthread() instead.