linux-kernel - Re: [PATCH] IB/rxe: Don't clamp residual length to mtu

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Message-ID: <20170413120000.GI6734@linux-x5ow.site>
Date:   Thu, 13 Apr 2017 14:00:00 +0200
From:   Johannes Thumshirn <jthumshirn@...e.de>
To:     Moni Shoua <monis@...lanox.com>, Sagi Grimberg <sagi@...mberg.me>,
        Max Gurtovoy <maxg@...lanox.com>
Cc:     Linux Kernel Mailinglist <linux-kernel@...r.kernel.org>,
        linux-rdma@...r.kernel.org, Hannes Reinecke <hare@...e.de>
Subject: Re: [PATCH] IB/rxe: Don't clamp residual length to mtu

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

Hi Moni, Sagi and Max,

Any comments on this?

Thanks,
	Johannes

-- 
Johannes Thumshirn                                          Storage
jthumshirn@...e.de                                +49 911 74053 689
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