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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 B5FBBC35249 for ; Sun, 2 Feb 2020 22:30:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8A8662082E for ; Sun, 2 Feb 2020 22:30:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Foz5rILV" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727148AbgBBW3y (ORCPT ); Sun, 2 Feb 2020 17:29:54 -0500 Received: from mail-lj1-f195.google.com ([209.85.208.195]:47036 "EHLO mail-lj1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727034AbgBBW3y (ORCPT ); Sun, 2 Feb 2020 17:29:54 -0500 Received: by mail-lj1-f195.google.com with SMTP id x14so12554779ljd.13; Sun, 02 Feb 2020 14:29:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=ZP2sBFBGkO5bsS7Y1zFf5pSNHFa7vlci0txeV2iOQs8=; b=Foz5rILVXxvGYBMBZLrVoGtWArCXNaGGwQ6xHp1AzJMc9crUGa2ucphj3ibX0DovEw mriYWnlneCYIIAflakMGGPTTI+2icDh6V8XZqJvpQTAPZk31yHAOamprgbgPe2CJUrp9 zoW5bbGA3v6nhenmjeGBu7zK5Cwt17OP8ZTgfOSh2ZiVsiEheAA/oifiCEmvcQSElDbm sWbR9Ab+VmcXaFKXr5TCsCIa3xlvP2ULMlSFX7X80X2Cl0CCZLLOjETaEiV1/AOBUXyR /i09JuIkxzURaG8Oo51ZXoXZ94LCbFlKBoeDqv/v1sTvxZTwj623oeMKgYxLxixbuvDB vupw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=ZP2sBFBGkO5bsS7Y1zFf5pSNHFa7vlci0txeV2iOQs8=; b=hbNiIFhbhbrIcNJR6YpMyXPtG1AMoVMUmA/UJ/fOGXjejTeVS9EdhvwOQ5KPyJYTYM lpH4NwavI8oRE2rjKUSB8oOENgOSmO5gS0bF0dA6qciK3MeyiFoqS2WffIygoXFHLIXK rtbREut/dgYigWFX9kWouK3VLYG/IY6xLiumPV9XZyU2l84fICCYoxbZh7PoYMmZIErI nMrAjgCsuE3zPCE08P8KgO30LM7SUVZj2j5PCcRN8J5QU5RKTtvGQVosOVcV3QzaiuzC fKhSDQN8jdmNPLg0Hfv79T6Kfnl2wH8WXQoPt9CT/LfZ5lxfnPiKPArYCBPRUffnhrmE HqHg== X-Gm-Message-State: APjAAAWl60wygNT4U9wYsCENiKPm+kyUadasizj+O5vOpYO304g7kjjK tt7P0G4fB4WYH1XUDRsT/rxbOQPt X-Google-Smtp-Source: APXvYqzRCGNXj+IOjPjeU03a0TzNCfEW4cu1YI3DZXwXaGg8TKKygCW7AJVzHhjJgyWzM5GUUJvbmg== X-Received: by 2002:a2e:574d:: with SMTP id r13mr11918813ljd.63.1580682592154; Sun, 02 Feb 2020 14:29:52 -0800 (PST) Received: from localhost.localdomain (79-139-233-37.dynamic.spd-mgts.ru. [79.139.233.37]) by smtp.gmail.com with ESMTPSA id b190sm8050307lfd.39.2020.02.02.14.29.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 02 Feb 2020 14:29:51 -0800 (PST) From: Dmitry Osipenko To: Laxman Dewangan , Vinod Koul , Dan Williams , Thierry Reding , Jonathan Hunter , =?UTF-8?q?Micha=C5=82=20Miros=C5=82aw?= Cc: dmaengine@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v7 04/19] dmaengine: tegra-apb: Prevent race conditions on channel's freeing Date: Mon, 3 Feb 2020 01:28:39 +0300 Message-Id: <20200202222854.18409-5-digetx@gmail.com> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20200202222854.18409-1-digetx@gmail.com> References: <20200202222854.18409-1-digetx@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org It's incorrect to check the channel's "busy" state without taking a lock. That shouldn't cause any real troubles, nevertheless it's always better not to have any race conditions in the code. Acked-by: Jon Hunter Signed-off-by: Dmitry Osipenko --- drivers/dma/tegra20-apb-dma.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c index f56881500a23..766c2c9eac8e 100644 --- a/drivers/dma/tegra20-apb-dma.c +++ b/drivers/dma/tegra20-apb-dma.c @@ -1294,8 +1294,7 @@ static void tegra_dma_free_chan_resources(struct dma_chan *dc) dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id); - if (tdc->busy) - tegra_dma_terminate_all(dc); + tegra_dma_terminate_all(dc); spin_lock_irqsave(&tdc->lock, flags); list_splice_init(&tdc->pending_sg_req, &sg_req_list); -- 2.24.0