From mboxrd@z Thu Jan 1 00:00:00 1970 From: torn5 Subject: Possible bug on SRP device delete Date: Mon, 13 Dec 2010 17:32:01 +0100 Message-ID: <4D064A81.6000607@shiftmail.org> Mime-Version: 1.0 Content-Type: text/plain; format=flowed; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-rdma List-Id: linux-rdma@vger.kernel.org Hello all, on the SCST-devel mailing list I posed the following question regarding the removal of mapped SRP disks. I have been suggested to the RDMA mailing list as it might be an ib_srp bug: >> 5) If I echo one line of ibsrpdm -c to >> /sys/class/infiniband_srp/srp-mthca0-1/add_target so to add a >> srp disk >> to my system, what happens is that another srp_host gets >> created. If I >> later remove the drive with "echo 1 > >> /sys/block/sdX/device/delete", the >> /sys/class/srp_hosts/srp_hostXY remains. Now after having >> remapped and >> deleted a few times the disk I am totally polluted of srp_host's. >> Another serious problem is that srp_daemon (from srptools) >> thinks the >> disk is still connected because it sees the previous >> srp_host, and won't >> reconnect it (won't recreate the sdX device). >> So what is the proper way to unmap a srp drive also deleting >> the srp_host? >> >> >> Seems like an ib_srp bug to me. Please report this on the >> linux-rdma mailing list >> (http://vger.kernel.org/vger-lists.html#linux-rdma). > Will do. What part seems a bug, the fact srp_hostXY does not go > away together with the device? > > > Please keep in mind that with the SRP protocol multiple LUNs share one > RDMA channel. That RDMA channel won't be closed and reopened because a > single host is deleted. ib_srp however should reconnect the RDMA > channel if /eh_host_reset_handler/ is invoked on /ib_srp/. > Notes: > - IMHO ib_srp should be modified such that it reports SCSI commands as > failed as soon as an IB error completion has been received instead of > waiting until these commands time out. That would make ib_srp recover > much more quickly from cable reconnects or SRP target restarts. > - Please don't use sg_reset on ib_srp, or you will hit this: > https://bugzilla.kernel.org/show_bug.cgi?id=13893. I can't currently understand the whole explanation, but please have a look if you think there is a bug. Also I would like to know, as per my original question, what was the correct procedure for also removing the srp_host. There should be some way to remove it, shouldn't it? Thank you -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html