On Thu, Apr 6, 2017 at 3:49 PM, Johannes Thumshirn <jthumshirn@xxxxxxx> 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 <jthumshirn@xxxxxxx> > Cc: Hannes Reinecke <hare@xxxxxxx> > Cc: Sagi Grimberg <sagi@xxxxxxxxxxx> > Cc: Max Gurtovoy <maxg@xxxxxxxxxxxx> > --- > drivers/infiniband/sw/rxe/rxe_resp.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c b/drivers/infiniband/sw/rxe/rxe_resp.c > index c9dd385..58764df 100644 > --- a/drivers/infiniband/sw/rxe/rxe_resp.c > +++ b/drivers/infiniband/sw/rxe/rxe_resp.c > @@ -478,8 +478,6 @@ static enum resp_states check_rkey(struct rxe_qp *qp, > state = RESPST_ERR_LENGTH; > goto err; > } > - > - qp->resp.resid = mtu; > } else { > if (pktlen != resid) { > state = RESPST_ERR_LENGTH; > -- > 2.10.2 > > -- Thanks Johannes Acked-by: Moni Shoua <monis@xxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html