From mboxrd@z Thu Jan 1 00:00:00 1970 From: Johannes Thumshirn Subject: Re: [PATCH] IB/rxe: Don't clamp residual length to mtu Date: Tue, 25 Apr 2017 09:29:38 +0200 Message-ID: <20170425072938.GB16843@linux-x5ow.site> References: <20170406124944.11074-1-jthumshirn@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Return-path: Content-Disposition: inline In-Reply-To: <20170406124944.11074-1-jthumshirn-l3A5Bk7waGM@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Doug Ledford Cc: Linux Kernel Mailinglist , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Hannes Reinecke , Sagi Grimberg , Max Gurtovoy , Moni Shoua , Sean Hefty , Hal Rosenstock List-Id: linux-rdma@vger.kernel.org On Thu, Apr 06, 2017 at 02:49:44PM +0200, Johannes Thumshirn wrote: > When reading a RDMA WRITE FIRST packet we copy the DMA length from the RDMA > header into the qp->resp.resid variable for later use. Later in check_rkey() > we clamp it to the MTU if the packet is an RDMA WRITE packet and has a > residual length bigger than the MTU. Later in write_data_in() we subtract the > payload of the packet from the residual length. If the packet happens to have a > payload of exactly the MTU size we end up with a residual length of 0 despite > the packet not being the last in the conversation. When the next packet in the > conversation arrives, we don't have any residual length left and thus set the QP > into an error state. > > This broke NVMe over Fabrics functionality over rdma_rxe.ko > > The patch was verified using the following test. > > # echo eth0 > /sys/module/rdma_rxe/parameters/add > # nvme connect -t rdma -a 192.168.155.101 -s 1023 -n nvmf-test > # mkfs.xfs -fK /dev/nvme0n1 > meta-data=/dev/nvme0n1 isize=256 agcount=4, agsize=65536 blks > = sectsz=4096 attr=2, projid32bit=1 > = crc=0 finobt=0, sparse=0 > data = bsize=4096 blocks=262144, imaxpct=25 > = sunit=0 swidth=0 blks > naming =version 2 bsize=4096 ascii-ci=0 ftype=1 > log =internal log bsize=4096 blocks=2560, version=2 > = sectsz=4096 sunit=1 blks, lazy-count=1 > realtime =none extsz=4096 blocks=0, rtextents=0 > # mount /dev/nvme0n1 /tmp/ > [ 148.923263] XFS (nvme0n1): Mounting V4 Filesystem > [ 148.961196] XFS (nvme0n1): Ending clean mount > # dd if=/dev/urandom of=test.bin bs=1M count=128 > 128+0 records in > 128+0 records out > 134217728 bytes (134 MB, 128 MiB) copied, 0.437991 s, 306 MB/s > # sha256sum test.bin > cde42941f045efa8c4f0f157ab6f29741753cdd8d1cff93a6b03649d83c4129a test.bin > # cp test.bin /tmp/ > sha256sum /tmp/test.bin > cde42941f045efa8c4f0f157ab6f29741753cdd8d1cff93a6b03649d83c4129a /tmp/test.bin > > Signed-off-by: Johannes Thumshirn > Cc: Hannes Reinecke > Cc: Sagi Grimberg > Cc: Max Gurtovoy > --- Doug anything left here? I already have an Ack from Moni. This patch is needed to get NVMe over Fabrics working on rxe so I'd like to see it in v4.12. Thanks, Johannes -- Johannes Thumshirn Storage jthumshirn-l3A5Bk7waGM@public.gmane.org +49 911 74053 689 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg) Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850 -- 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