From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [net-2.6 PATCH 2/3] ixgbe: In SR-IOV mode insert delay before bring the adapter up Date: Fri, 26 Mar 2010 11:57:53 -0700 (PDT) Message-ID: <20100326.115753.160228163.davem@davemloft.net> References: <20100324193515.6078.27035.stgit@localhost.localdomain> <20100324193608.6078.61157.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, gospo@redhat.com, gregory.v.rose@intel.com To: jeffrey.t.kirsher@intel.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:50457 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751246Ab0CZS53 (ORCPT ); Fri, 26 Mar 2010 14:57:29 -0400 In-Reply-To: <20100324193608.6078.61157.stgit@localhost.localdomain> Sender: netdev-owner@vger.kernel.org List-ID: From: Jeff Kirsher Date: Wed, 24 Mar 2010 12:36:08 -0700 > From: Greg Rose > > VFs running in guest VMs do not respond in as timely a manner to > PF indication it is going down as they do when running in the host > domain. If the adapter is in SR-IOV mode insert a two second delay > to guarantee that all VFs have had time to respond to the PF reset. > In any case resetting the PF while VFs are active should be > discouraged but if it must be done then there will be a two > second delay to help synchronize resets among the PF and all the > VFs. > > Signed-off-by: Greg Rose > Signed-off-by: Jeff Kirsher Applied, but... I know why you might need to do this, but this is going to completely explode if someone tries to, f.e. bring up thousands of these interfaces. Maybe that's not practical, but is, say, 30? With a 2 second delay each that's a full minute hanging at the command line or the bootup scripts. My point is that this behavior is basically extremely undesirable.