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See http://www.infradead.org/rpr.html X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Christoph Hellwig , "Anner, Ran" , Sagi Grimberg , "linux-nvme@lists.infradead.org" , "Engel, Amit" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Fri, Aug 14, 2020 at 09:02:20AM -0700, Keith Busch wrote: > Couldn't you just clear the REQ_DRIVER_FAILFAST flag to get the existing > retry mechanisms working in this path? That would only retry locally and thus not really help. > > And while it looks fine for fabrics, PCIe doesn't have the implied HOST > ID connection that makes reservations do the right thing across > different paths. Automatic path failover retries for PCIe may have the > wrong result. You need a host id for reservations to work properly, as without that they won't actually be persistent. Unfortunasly NVMe allows reservations without a hostid with some rather broken semantics instead of just failing them, so applications that do use reservations needs to ensure a host id is set. _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme