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Tsirkin" To: Yongji Xie Cc: Jason Wang , Liu Xiaodong , Maxime Coquelin , Stefan Hajnoczi , virtualization , linux-kernel , songmuchun@bytedance.com Subject: Re: [PATCH 5/6] vduse: Support registering userspace memory for IOTLB Message-ID: <20220629072825-mutt-send-email-mst@kernel.org> References: <20220629082541.118-1-xieyongji@bytedance.com> <20220629082541.118-6-xieyongji@bytedance.com> <20220629043539-mutt-send-email-mst@kernel.org> <20220629055241-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Spam-Status: No, score=-3.2 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_LOW, 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 Wed, Jun 29, 2022 at 06:19:31PM +0800, Yongji Xie wrote: > > No i mean you decrement the lock twice. Question is can two bounce > > buffers share a page? > > > > I think we can't. I will find a way to prevent it. > > Thanks, > Yongji I guess it doesn't matter much then. -- MST