From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] ibmveth: Fix alignment of rx queue bug Date: Wed, 05 Sep 2012 17:45:43 -0400 (EDT) Message-ID: <20120905.174543.111505618029273524.davem@davemloft.net> References: <50469FC1.2000202@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: santil@linux.vnet.ibm.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:45030 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755072Ab2IEVpo (ORCPT ); Wed, 5 Sep 2012 17:45:44 -0400 In-Reply-To: <50469FC1.2000202@linux.vnet.ibm.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Santiago Leon Date: Tue, 04 Sep 2012 19:41:37 -0500 > This patch fixes a bug found by Nish Aravamudan > (https://lkml.org/lkml/2012/5/15/220) where the driver is not following > the spec (it is not aligning the rx buffer on a 16-byte boundary) and the > hypervisor aborts the registration, making the device unusable. > > The fix follows BenH's recommendation (https://lkml.org/lkml/2012/7/20/461) > to replace the kmalloc+map for a single call to dma_alloc_coherent() > because that function always aligns to a 16-byte boundary. > > The stable trees will run into this bug whenever the rx buffer kmalloc call > returns something not aligned on a 16-byte boundary. > > Cc: > Signed-off-by: Santiago Leon Applied, thanks.