From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [net-2.6 v2 5/7] ixgbe: DDP last buffer size work around Date: Fri, 28 Jan 2011 11:51:00 -0800 (PST) Message-ID: <20110128.115100.226772144.davem@davemloft.net> References: <1296217743-30093-1-git-send-email-jeffrey.t.kirsher@intel.com> <1296217743-30093-6-git-send-email-jeffrey.t.kirsher@intel.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: amir.hanania@intel.com, netdev@vger.kernel.org, gospo@redhat.com, bphilips@novell.com To: jeffrey.t.kirsher@intel.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:56579 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752793Ab1A1Tu0 (ORCPT ); Fri, 28 Jan 2011 14:50:26 -0500 In-Reply-To: <1296217743-30093-6-git-send-email-jeffrey.t.kirsher@intel.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Jeff Kirsher Date: Fri, 28 Jan 2011 04:29:01 -0800 > From: Amir Hanania > > We found a hardware erratum on 82599 hardware that can lead to buffer > overwriting if the last buffer in FCoE DDP is exactly PAGE_SIZE. > If this is the case, we will make sure that there is no HW access to > this buffer. > > Please see the 82599 Specification Update for more information. > > Signed-off-by: Amir Hanania > Tested-by: Ross Brattain > Signed-off-by: Jeff Kirsher Jeff, I still think this change is bogus. PAGE_SIZE is variable, so the chip can't possibly only BUG on that specific value. Maybe the condition is "any power-of-2 larger than or equal to 4096"? Or something like that? I pointed this out last night, and I was really hoping I'd get actual feedback on this issue before you're respin your tree. I'm not pulling in these changes until I get a human being telling me what the situation is here with this bug.