From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88294C433E2 for ; Fri, 19 Mar 2021 22:15:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 49EE261992 for ; Fri, 19 Mar 2021 22:15:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230523AbhCSWP1 (ORCPT ); Fri, 19 Mar 2021 18:15:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43252 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230285AbhCSWPV (ORCPT ); Fri, 19 Mar 2021 18:15:21 -0400 Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BD81BC06175F; Fri, 19 Mar 2021 15:15:20 -0700 (PDT) Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94) (envelope-from ) id 1lNNOl-000kRz-12; Fri, 19 Mar 2021 23:15:15 +0100 Message-ID: <14f7bbfea8a17dcd12e7d40641198063428d19b3.camel@sipsolutions.net> Subject: Re: systemd-rfkill regression on 5.11 and later kernels From: Johannes Berg To: Takashi Iwai Cc: Emmanuel Grumbach , linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org Date: Fri, 19 Mar 2021 23:15:14 +0100 In-Reply-To: <9db9d9ae751a50c9fd1da1ee3bd4c564546ce1c5.camel@sipsolutions.net> (sfid-20210318_121746_242488_98446BA5) References: <54859a03b8789a2800596067e06c8adb49a107f5.camel@sipsolutions.net> <9db9d9ae751a50c9fd1da1ee3bd4c564546ce1c5.camel@sipsolutions.net> (sfid-20210318_121746_242488_98446BA5) Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.38.4 (3.38.4-1.fc33) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-malware-bazaar: not-scanned Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2021-03-18 at 12:16 +0100, Johannes Berg wrote: > > Yeah, that's a dilemma. An oft-seen trick is to add more bytes for > > the future use, e.g. extend to 16 bytes and fill 0 for the remaining. > > Yeah, I guess I could stick a reserved[15] there, it's small enough. Actually, that doesn't really help anything either. If today I require that the reserved bytes are sent as 0 by userspace, then any potential expansion that requires userspace to set it will break when userspace does it and runs on an old kernel. If I don't require the reserved bytes to be set to 0 then somebody will invariably get it wrong and send garbage, and then we again cannot extend it. So ... that all seems pointless. I guess I'll send the patch as it is now. johannes