From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurence Oberman Subject: Re: [PATCH 11/11] IB/srp: Prevent mapping failures Date: Mon, 9 May 2016 18:50:06 -0400 (EDT) Message-ID: <169904890.34764265.1462834206901.JavaMail.zimbra@redhat.com> References: <571A936F.7040409@sandisk.com> <2102017158.34060891.1462478304470.JavaMail.zimbra@redhat.com> <572BA98F.4090109@sandisk.com> <572BAA6F.1060607@sandisk.com> <804753248.34153510.1462481756460.JavaMail.zimbra@redhat.com> <572BBDC0.5070205@sandisk.com> <1133135399.34245490.1462485666601.JavaMail.zimbra@redhat.com> <572BCD59.7010701@sandisk.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <572BCD59.7010701-XdAiOPVOjttBDgjK7y7TUQ@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Bart Van Assche Cc: Christoph Hellwig , Doug Ledford , Sagi Grimberg , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rdma@vger.kernel.org ----- Original Message ----- > From: "Bart Van Assche" > To: "Laurence Oberman" > Cc: "Christoph Hellwig" , "Doug Ledford" , "Sagi Grimberg" , > linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > Sent: Thursday, May 5, 2016 6:46:49 PM > Subject: Re: [PATCH 11/11] IB/srp: Prevent mapping failures > > On 05/05/2016 03:01 PM, Laurence Oberman wrote: > > Yep, something has changed upstream here to bring this out. > > I will modify the SRP initiator such that more mr's are allocated if > max_sectors > max_sectors_per_mr. That should allow 4 MB I/O even with > mlx4 and fast registration and without the risk of encountering a > mapping failure. > > Bart. > > -- > 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 > Hello Bart I spent the weekend testing the RHEL6 kernel + Mellanox Ofed. Its rock solid. On both the latest upstream and the RHEL7.2 kernel we have mapping failures with 4MB max_sector_kb sizes. In addition the latest RHEL 7.2 kernel + Mellanox Ofed sees the same mapping issues. This seems to suggest its not confined to only code changes Mellanox has in Ofed ib_srp drivers Are we looking at a combination of kernel changes and ib_srp changes here to correct this. Or do you think this will be resolved in the end by just changes to the ib_srp driver code. If there is any other data you want me to capture or debug please do let me know. I have started investigating the full flow of I/O from the upper layers through the kernel to the ib_srp layer to see what is different in RHEL6 and why this issue is not apparent. Thanks as always for your assistance here. Laurence -- 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