Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754212AbcJNKAe (ORCPT ); Fri, 14 Oct 2016 06:00:34 -0400 Received: from s3.sipsolutions.net ([5.9.151.49]:58141 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754161AbcJNKA3 (ORCPT ); Fri, 14 Oct 2016 06:00:29 -0400 Message-ID: <1476439212.31114.37.camel@sipsolutions.net> Subject: Re: [mac80211] BUG_ON with current -git (4.8.0-11417-g24532f7) From: Johannes Berg To: Ard Biesheuvel Cc: Andy Lutomirski , Stephen Rothwell , "linux-next@vger.kernel.org" , Sergey Senozhatsky , Network Development , Sergey Senozhatsky , Herbert Xu , "David S. Miller" , Linux Wireless List , "linux-kernel@vger.kernel.org" , Jouni Malinen Date: Fri, 14 Oct 2016 12:00:12 +0200 In-Reply-To: (sfid-20161014_113557_975987_6F520981) References: <20161010150358.GA514@swordfish> <20161010153050.GA836@swordfish> <1476263106.5271.23.camel@sipsolutions.net> <20161012141245.GA436@swordfish> <1476282127.5271.30.camel@sipsolutions.net> <1476338524.4904.1.camel@sipsolutions.net> <20161013134252.GA583@swordfish> <1476366354.4904.31.camel@sipsolutions.net> <1476429916.4382.12.camel@sipsolutions.net> <1476433699.31114.6.camel@sipsolutions.net> <1476434561.31114.7.camel@sipsolutions.net> <1476435303.31114.14.camel@sipsolutions.net> <1476436248.31114.21.camel@sipsolutions.net> <1476437149.31114.27.camel@sipsolutions.net> (sfid-20161014_113557_975987_6F520981) Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.20.5-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 683 Lines: 18 > So why is the performance hit acceptable for ESP but not for WPA? We > could easily implement the same thing, i.e., > kmalloc(GFP_ATOMIC)/kfree the aead_req struct rather than allocate it > on the stack Yeah, maybe we should. It's likely a much bigger allocation, but I don't actually know if that affects speed. In most cases where you want high performance we never hit this anyway since we'll have hardware crypto. I know for our (Intel's) devices we normally never hit these code paths. But on the other hand, you also did your changes for a reason, and the only reason I can see of that is performance. So you'd be the one with most "skin in the game", I guess? johannes