From mboxrd@z Thu Jan 1 00:00:00 1970 From: davem@davemloft.net (David Miller) Date: Tue, 11 Dec 2012 13:30:58 -0500 (EST) Subject: [PATCH v2 1/1] net: ethernet: davinci_cpdma: Add boundary for rx and tx descriptors In-Reply-To: <1355197433-7492-1-git-send-email-mugunthanvnm@ti.com> References: <1355197433-7492-1-git-send-email-mugunthanvnm@ti.com> Message-ID: <20121211.133058.2238010228178961245.davem@davemloft.net> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org You cannot do this. After your changes the driver no longer does any TX flow control. It never stops the TX queue and never wakes it up later. It just drops packets on the floor when it runs out of descriptors. This breaks everything, and in particular packet schedulers and TCP. I'm not applying this.