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=-17.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, UNWANTED_LANGUAGE_BODY,USER_AGENT_GIT 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 944C8C07E95 for ; Mon, 19 Jul 2021 16:29:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F80B61928 for ; Mon, 19 Jul 2021 16:29:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347498AbhGSPsQ (ORCPT ); Mon, 19 Jul 2021 11:48:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:45036 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349292AbhGSPo6 (ORCPT ); Mon, 19 Jul 2021 11:44:58 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 81B1F6162B; Mon, 19 Jul 2021 16:24:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626711858; bh=sEkRuphTMwr2a3ubNhQqvFiqPbchASYk6LFAm9qznhE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CH+o+k6LsKBXsD71VupglyJ8pjdrHfzLKF3Wqif89z+bUZ90lcpBHqK5PaHak34we ruphkAm3bK9P0npuC+Y4vyTcoxXIO4xY5P4nbt0WQ/vede2WMW3Uie3KC+tlml8XxE MyKdGmj/Yg8YHo1PS2R/gVHQWP0KnuPcM21YH+MI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Geoffrey D. Bennett" , Takashi Iwai , Sasha Levin Subject: [PATCH 5.12 114/292] ALSA: usb-audio: scarlett2: Fix data_mutex lock Date: Mon, 19 Jul 2021 16:52:56 +0200 Message-Id: <20210719144946.242136044@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210719144942.514164272@linuxfoundation.org> References: <20210719144942.514164272@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Geoffrey D. Bennett [ Upstream commit 9b5ddea9ce5a68d7d2bedcb69901ac2a86c96c7b ] The private->vol_updated flag was being checked outside of the mutex_lock/unlock() of private->data_mutex leading to the volume data being fetched twice from the device unnecessarily or old volume data being returned. Update scarlett2_*_ctl_get() and include the private->vol_updated flag check inside the critical region. Signed-off-by: Geoffrey D. Bennett Link: https://lore.kernel.org/r/20210620164643.GA9216@m.b4.vu Signed-off-by: Takashi Iwai Signed-off-by: Sasha Levin --- sound/usb/mixer_scarlett_gen2.c | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-) diff --git a/sound/usb/mixer_scarlett_gen2.c b/sound/usb/mixer_scarlett_gen2.c index 1982e67a0f32..2ea41c8eafd1 100644 --- a/sound/usb/mixer_scarlett_gen2.c +++ b/sound/usb/mixer_scarlett_gen2.c @@ -1033,11 +1033,10 @@ static int scarlett2_master_volume_ctl_get(struct snd_kcontrol *kctl, struct usb_mixer_interface *mixer = elem->head.mixer; struct scarlett2_mixer_data *private = mixer->private_data; - if (private->vol_updated) { - mutex_lock(&private->data_mutex); + mutex_lock(&private->data_mutex); + if (private->vol_updated) scarlett2_update_volumes(mixer); - mutex_unlock(&private->data_mutex); - } + mutex_unlock(&private->data_mutex); ucontrol->value.integer.value[0] = private->master_vol; return 0; @@ -1051,11 +1050,10 @@ static int scarlett2_volume_ctl_get(struct snd_kcontrol *kctl, struct scarlett2_mixer_data *private = mixer->private_data; int index = elem->control; - if (private->vol_updated) { - mutex_lock(&private->data_mutex); + mutex_lock(&private->data_mutex); + if (private->vol_updated) scarlett2_update_volumes(mixer); - mutex_unlock(&private->data_mutex); - } + mutex_unlock(&private->data_mutex); ucontrol->value.integer.value[0] = private->vol[index]; return 0; @@ -1319,11 +1317,10 @@ static int scarlett2_button_ctl_get(struct snd_kcontrol *kctl, struct usb_mixer_interface *mixer = elem->head.mixer; struct scarlett2_mixer_data *private = mixer->private_data; - if (private->vol_updated) { - mutex_lock(&private->data_mutex); + mutex_lock(&private->data_mutex); + if (private->vol_updated) scarlett2_update_volumes(mixer); - mutex_unlock(&private->data_mutex); - } + mutex_unlock(&private->data_mutex); ucontrol->value.enumerated.item[0] = private->buttons[elem->control]; return 0; -- 2.30.2