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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 3D4BFC433E9 for ; Thu, 18 Mar 2021 08:28:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 15F8A64F04 for ; Thu, 18 Mar 2021 08:28:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229643AbhCRI1c (ORCPT ); Thu, 18 Mar 2021 04:27:32 -0400 Received: from mx2.suse.de ([195.135.220.15]:36512 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229708AbhCRI1U (ORCPT ); Thu, 18 Mar 2021 04:27:20 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id F1938AC17; Thu, 18 Mar 2021 08:27:18 +0000 (UTC) Date: Thu, 18 Mar 2021 09:27:18 +0100 Message-ID: From: Takashi Iwai To: Emmanuel Grumbach Cc: linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org Subject: systemd-rfkill regression on 5.11 and later kernels User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/25.3 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, we've received a bug report about rfkill change that was introduced in 5.11. While the systemd-rfkill expects the same size of both read and write, the kernel rfkill write cuts off to the old 8 bytes while read gives 9 bytes, hence it leads the error: https://github.com/systemd/systemd/issues/18677 https://bugzilla.opensuse.org/show_bug.cgi?id=1183147 As far as I understand from the log in the commit 14486c82612a, this sounds like the intended behavior. But if this was implemented in that way just for the compatibility reason, it actually is worse, introducing a regression. Although this can be addressed easily in the systemd side, the current kernel behavior needs reconsideration, IMO. thanks, Takashi