Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754986AbbEGKvo (ORCPT ); Thu, 7 May 2015 06:51:44 -0400 Received: from mail-ie0-f178.google.com ([209.85.223.178]:34526 "EHLO mail-ie0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750784AbbEGKvl (ORCPT ); Thu, 7 May 2015 06:51:41 -0400 MIME-Version: 1.0 In-Reply-To: <1430993477.30151.6.camel@suse.de> References: <1430992159-27783-1-git-send-email-ruslan.bilovol@gmail.com> <1430993477.30151.6.camel@suse.de> Date: Thu, 7 May 2015 13:51:40 +0300 Message-ID: Subject: Re: [PATCH] net: usb: allow MTU that is a multiple of USB packet size From: Ruslan Bilovol To: Oliver Neukum Cc: netdev , "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1266 Lines: 36 Hi Oliver, On Thu, May 7, 2015 at 1:11 PM, Oliver Neukum wrote: > On Thu, 2015-05-07 at 12:49 +0300, Ruslan Bilovol wrote: >> Current usbnet driver rejects setting MTU that is a multiple >> of USB endpoint's wMaxPacketSize size. However, it may only >> lead to possible performance degradation but is not so >> critical that its using should be prohibited. So allow it >> but also warn user about possible issue. > > We have reports about devices reacting badly to ZLPs. > Unless you have a compelling reasons for this change > I have to reject it. What devices do you mean here: USB network adapters or USB host controllers? If it's just network adapters, then we can create some kind of quirk handling for them and do not disable this functionality just because some buggy device can't work with it. My device works fine with ZLPs so I want to use this particular MTU under Linux like I do it under other operation systems. Regards, Ruslan > > Regards > Oliver > > NACK > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/