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Peter Anvin" , linux-kernel@vger.kernel.org Subject: Re: [PATCH] atomic: Put the fetching of the old value into the loop when doing atomic CAS Message-ID: References: <20220224082438.580191-1-hhusjrsjr@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220224082438.580191-1-hhusjrsjr@gmail.com> X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RDNS_NONE,SPF_HELO_NONE,T_SCC_BODY_TEXT_LINE autolearn=no 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 Thu, Feb 24, 2022 at 04:24:38PM +0800, Junru Shen wrote: > Put the acquisition of the expected value inside the loop to prevent an infinite loop when it does not match. NAK, this is broken.