From patchwork Thu Oct 3 15:53:55 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 175120 Delivered-To: patch@linaro.org Received: by 2002:a92:7e96:0:0:0:0:0 with SMTP id q22csp547287ill; Thu, 3 Oct 2019 09:22:34 -0700 (PDT) X-Google-Smtp-Source: APXvYqzYd5H+5udil08rb6NQ/N/8oL5vAey+kCtnC6kNqFbGp0r3QLoxapOPXGRm/GWttES0+YNT X-Received: by 2002:a17:906:134b:: with SMTP id x11mr8342265ejb.272.1570119753585; Thu, 03 Oct 2019 09:22:33 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1570119753; cv=none; d=google.com; s=arc-20160816; b=c51zCGawuy+L66fjouX99mTv/+vX69UQfM/YRBI4qkNbZuccAi+jEReJu7p3T4v2DZ e1F3vc6auLzSuuPeEbCmHXnCTypBfiLtEiBq0pjhxcaQ6i7EOwdG1hDvGwBXFEmlouep Tm4uSeBmB1pzvjeAp3mGs/BaeJjvjd/rYwoFAKYYzShec01UyC9kfs+RSUh/uX5tgtxo XQuwkp3Sbk7SGm2yPdFv4Z/0st65Tj/BGOK5YnSlafdXh9/LyMqYMalmVaRMjFXy9kIG doQkrKZe7TdJyRvzY5tbfIKZcoXCtQwayPaIAzbi71exYO5x+vUQrRe6UQkYxQc0HDYM NeUQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=DyP8hsKscWzg1pYydjcE7twgJHOMiPSUXKozvohJTSw=; b=YEaXON6T+K4IDL2xyH0bK7YEWyR+4I7jNyg7rJslW7MPwTC4owkZRmfwylqj1gF6CL wYQKpYrRBmEWB3pld8T59zZ6UaBRNL8tH7/Z+s3SzIrwT2snpibRl/1nSgTiAOPZqdJT tqxN7uBdinbSKzcGzx0M3QwjG1Q7wFPsWutpDKqcxRdxHd52XuKiB1Bis/VJ51oedFbo d34io3WZ7xqFPXcZk7N4DqxQq+VcZk9XidnPDR1L7bAKp5DiMEzGP6acYZWWvP3CfCb+ ywdd7gTZaFKaPnD5Nyq7OJIMwPesLz8B4Ti3Njmfffj0EIg6ps/A2SPdFIcdn19nmOZU Ymeg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=md8Odipt; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id r9si1466232eju.10.2019.10.03.09.22.33; Thu, 03 Oct 2019 09:22:33 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=md8Odipt; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390242AbfJCQWE (ORCPT + 27 others); Thu, 3 Oct 2019 12:22:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:50528 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390229AbfJCQWB (ORCPT ); Thu, 3 Oct 2019 12:22:01 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 BCAF120865; Thu, 3 Oct 2019 16:21:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570119720; bh=zrdNoSnOeNZj5QJjLU3IpZ0WHzz72+SQAhpLfEHBe8A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=md8OdiptVzGPkWvj9vlzb7RLUcXHabwCg0MIB706oF+JaM0pfXnQE5G1z/QOB3G9L C/IgPZLbBgzofazObLIroBYDrLbXq2Znswk3d6OuIQjB1VyCHYrW4ia8jcIgjcrzW3 387I1WreIaZ+EGPWmjZ3hxgSOp8SECsulKMxP7xI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Max Kellermann , Wolfgang Rohdewald , Arnd Bergmann , Sean Young , Mauro Carvalho Chehab Subject: [PATCH 4.19 169/211] media: dont drop front-end reference count for ->detach Date: Thu, 3 Oct 2019 17:53:55 +0200 Message-Id: <20191003154526.075951948@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191003154447.010950442@linuxfoundation.org> References: <20191003154447.010950442@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnd Bergmann commit 14e3cdbb00a885eedc95c0cf8eda8fe28d26d6b4 upstream. A bugfix introduce a link failure in configurations without CONFIG_MODULES: In file included from drivers/media/usb/dvb-usb/pctv452e.c:20:0: drivers/media/usb/dvb-usb/pctv452e.c: In function 'pctv452e_frontend_attach': drivers/media/dvb-frontends/stb0899_drv.h:151:36: error: weak declaration of 'stb0899_attach' being applied to a already existing, static definition The problem is that the !IS_REACHABLE() declaration of stb0899_attach() is a 'static inline' definition that clashes with the weak definition. I further observed that the bugfix was only done for one of the five users of stb0899_attach(), the other four still have the problem. This reverts the bugfix and instead addresses the problem by not dropping the reference count when calling '->detach()', instead we call this function directly in dvb_frontend_put() before dropping the kref on the front-end. I first submitted this in early 2018, and after some discussion it was apparently discarded. While there is a long-term plan in place, that plan is obviously not nearing completion yet, and the current kernel is still broken unless this patch is applied. Link: https://patchwork.kernel.org/patch/10140175/ Link: https://patchwork.linuxtv.org/patch/54831/ Cc: Max Kellermann Cc: Wolfgang Rohdewald Cc: stable@vger.kernel.org Fixes: f686c14364ad ("[media] stb0899: move code to "detach" callback") Fixes: 6cdeaed3b142 ("media: dvb_usb_pctv452e: module refcount changes were unbalanced") Signed-off-by: Arnd Bergmann Signed-off-by: Sean Young Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/dvb-core/dvb_frontend.c | 4 +++- drivers/media/usb/dvb-usb/pctv452e.c | 8 -------- 2 files changed, 3 insertions(+), 9 deletions(-) --- a/drivers/media/dvb-core/dvb_frontend.c +++ b/drivers/media/dvb-core/dvb_frontend.c @@ -164,6 +164,9 @@ static void dvb_frontend_free(struct kre static void dvb_frontend_put(struct dvb_frontend *fe) { + /* call detach before dropping the reference count */ + if (fe->ops.detach) + fe->ops.detach(fe); /* * Check if the frontend was registered, as otherwise * kref was not initialized yet. @@ -3035,7 +3038,6 @@ void dvb_frontend_detach(struct dvb_fron dvb_frontend_invoke_release(fe, fe->ops.release_sec); dvb_frontend_invoke_release(fe, fe->ops.tuner_ops.release); dvb_frontend_invoke_release(fe, fe->ops.analog_ops.release); - dvb_frontend_invoke_release(fe, fe->ops.detach); dvb_frontend_put(fe); } EXPORT_SYMBOL(dvb_frontend_detach); --- a/drivers/media/usb/dvb-usb/pctv452e.c +++ b/drivers/media/usb/dvb-usb/pctv452e.c @@ -913,14 +913,6 @@ static int pctv452e_frontend_attach(stru &a->dev->i2c_adap); if (!a->fe_adap[0].fe) return -ENODEV; - - /* - * dvb_frontend will call dvb_detach for both stb0899_detach - * and stb0899_release but we only do dvb_attach(stb0899_attach). - * Increment the module refcount instead. - */ - symbol_get(stb0899_attach); - if ((dvb_attach(lnbp22_attach, a->fe_adap[0].fe, &a->dev->i2c_adap)) == NULL) err("Cannot attach lnbp22\n");