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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT 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 4EE20C6786E for ; Fri, 26 Oct 2018 10:59:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 15DE12085B for ; Fri, 26 Oct 2018 10:59:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="niLVwYA+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 15DE12085B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727377AbeJZTf4 (ORCPT ); Fri, 26 Oct 2018 15:35:56 -0400 Received: from mail.kernel.org ([198.145.29.99]:37170 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726275AbeJZTf4 (ORCPT ); Fri, 26 Oct 2018 15:35:56 -0400 Received: from localhost (unknown [167.98.65.38]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E1C9A20856; Fri, 26 Oct 2018 10:59:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1540551558; bh=+WmK2EoimfOsr0XVBjFrvCTShi52p4aOPQbSisSRB7c=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=niLVwYA+Fn1W7LXJcu1IA3pcJdwU0aueIeM4KuhKnK30W8dH08Mck47MGm29+lNhT g4MxOTl39P0AQMwp8QrRtYIPm4RjbDzHsA1QaUAovSKeG06DJ2aRj0vUCk2wuaKAsk PvMQPH9eUH03aVrUl1S+yhHq7i7KQBjGtjLhZAfw= Date: Fri, 26 Oct 2018 06:59:16 -0400 From: Sasha Levin To: Johan Hovold Cc: stable@vger.kernel.org, linux-kernel@vger.kernel.org, =?iso-8859-1?Q?Bj=F8rn?= Mork Subject: Re: [PATCH AUTOSEL 3.18 04/98] USB: qcserial: Fix support for HP lt4112 LTE/HSPA+ Gobi 4G Modem Message-ID: <20181026105916.GE2015@sasha-vm> References: <20181025141853.214051-1-sashal@kernel.org> <20181025141853.214051-4-sashal@kernel.org> <20181026084920.GB27852@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20181026084920.GB27852@localhost> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 26, 2018 at 10:49:20AM +0200, Johan Hovold wrote: >On Thu, Oct 25, 2018 at 10:17:19AM -0400, Sasha Levin wrote: >> From: Bjørn Mork >> >> [ Upstream commit 59536da34513c594af2a6fd35ba65ea45b6960a1 ] >> >> The DEVICE_HWI type was added under the faulty assumption that Huawei >> devices based on Qualcomm chipsets and firmware use the static USB >> interface numbering known from Gobi devices. But this model does >> not apply to Huawei devices like the HP branded lt4112 (Huawei me906e). >> Huawei firmwares will dynamically assign interface numbers. Functions >> are renumbered when the firmware is reconfigured. >> >> Fix by changing the DEVICE_HWI type to use a simplified version >> of Huawei's subclass + protocol scheme: Blacklisting known network >> interface combinations and assuming the rest are serial. >> >> Reported-and-tested-by: Muri Nicanor >> Tested-by: Martin Hauke >> Cc: >> Fixes: e7181d005e84 ("USB: qcserial: Add support for HP lt4112 LTE/HSPA+ Gobi 4G Modem") >> Signed-off-by: Bjørn Mork >> Signed-off-by: Johan Hovold >> Signed-off-by: Sasha Levin > >This one is interesting though; it was marked for stable and has a >proper fixes tag for a commit that went into 4.19. That patch in turn >had a stable tag (new device id type patch) and was backported also to >other active stable trees at the time. > >Guess the stable maintainers need to check if the offending patch has >already been backported when determining how far back to apply a follow >up fix. > >Note that the stable tag above lacks a version comment (e.g. "# 4.19"), >but I can see how that may be too subtle to convey this (and not all >maintainers use those). Perhaps an explicit comment should just be added >in such cases. Right, the whole "fix for a fix" issue is what this patch series tries to address (you'll notice that *most* commits follow this pattern). I'm not sure why Greg's tools missed it to begin with, but hopefully this patch series will catch up with that. -- Thanks, Sasha