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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A73E3C5B559 for ; Fri, 6 Jun 2025 07:44:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Px7TUkiGLJQvkjO/71jKrxllILzPLzGA5siX95GH57I=; b=lWXspFgg7TmTeNkkPQ0Tcwfog6 jUofXqwCPb++2IhI657ri6gztN6BPoVWOLqF6Day7KKu5ocL9bLWMK8ooT8srz4qzpoYocE6x9nlv eRIdUSkr/oLjTb9gsMNn+5ar9p69sBSXqGoAAgWanXlbcHeRbuwt9eP+m784ZvT9/LBaK+4Qmm7Yo hnlsaAzrldiKIByn/rSKAUZdM+eIvDW0yb9bxG8SplvJ240sduFGUzBqfRzPftEQWtoLT9w11lf3g QpuaONfsvefv5OxtsVl0X9YoNN7TIrlc1+jD8bkZfi6/+Z0Ts//a5qW8+kO/oIycFqo1737cU7W1O dVQDZbqg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uNRkh-0000000HKbM-3GWZ; Fri, 06 Jun 2025 07:44:35 +0000 Received: from mail-wm1-x336.google.com ([2a00:1450:4864:20::336]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uNRiT-0000000HKPR-3tYx for linux-mediatek@lists.infradead.org; Fri, 06 Jun 2025 07:42:19 +0000 Received: by mail-wm1-x336.google.com with SMTP id 5b1f17b1804b1-450d668c2a1so20203515e9.0 for ; Fri, 06 Jun 2025 00:42:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1749195736; x=1749800536; darn=lists.infradead.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=Px7TUkiGLJQvkjO/71jKrxllILzPLzGA5siX95GH57I=; b=EoIHKf0vgRbwyk8XIIZGRwBBPOH2ouIv4FKsG9EGPRaZnjTrjwtKFNpnO0KlefjxyR xCkgA8QZ/Bqx4pYBF/3LfvAdjXhFq2zDNmGQQQoXbD9fP/cWcpihpACPO2eFzge7LcMi FA3y+GiOI0d20UwKebtL7aZ+UomF84M1/6jqw9dozGwim15EfO+eOsiFTM4h8h1PFCqn DD6EaHEQOyNW3GMoIy82mr1lumfzC6avblPZBOhNmiaNCfnQZJnPFr6/yz0oKTkI4EOr 08/7lIL2jCF8KTK5xEHA5odZaV8yLYsqgEgttSzySJBDl7iqj/Ymckmnin6Cg4G1i1yU 5Pfw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1749195736; x=1749800536; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=Px7TUkiGLJQvkjO/71jKrxllILzPLzGA5siX95GH57I=; b=MMV8L0lan5aI5WwoeilA42klMp3VbokdWbjY0OLqrjU0oKcoAX++tS+8l0NkA+T+Al 5+rr+ZuNRvtRVPrYgaSrTIcLPuNfVDlK9fh1G3Y+l+sUQtpgyrmR6eYY+myiCS7HQs0A 21510H+EWI3DB2Ap8YGF6k+sHa+nTN5qD81xcX0cLlxUulje1NNbtz5xXn3Ruzs/Le78 UPyERvkiftpvPHGvLzKBUcsT5xa8fGSy6qNNDmlFvoTzUu8Mxaj+EnMxCKpMcXfRO6Km SRM8dQfLN3b2iPg7c+KzuEehIzcIb5jlRHG8Xm7xGKro8zDhd8jb9PYgmuzIPNSrIXoN nqqQ== X-Forwarded-Encrypted: i=1; AJvYcCUVJTGJuaozToaO41888G3SmJEkRa+TjDsjtbO9VbhpSWEgXFoLANmGA3he39d9uuET76ugBFgPn5ee1+m4gQ==@lists.infradead.org X-Gm-Message-State: AOJu0Yx5ChY4p2cMOTn90LS+c/1tHTT98L4Y1j5Re4eAiNgTKg3C8vb/ r4R8smKx4NOuOErO1T48JG+sZ526Qd/xebpJd3i2x1bYUpfGvENlEHiyRwaQ7oT4uls= X-Gm-Gg: ASbGncuFT4zpFEEKVh32Q37B9k2/7AfnOR+TTi7vITnUJpFGxfa8RqCAnjfkiR63g+y T52U0H1bFa9MntYwNKkIq+BtpnwZYXD+JufThtX4xIBD5Xksw7rhRVt0Sa1TWaYcbe0O1chPn2c WGN3qLevLrX65Bmx9GnCDkXvafnzNVQXOrym5zlUvHWZGKPGSOSS2e4DXLSu82kR7yV78w36DqH WzfOiIeueQTAhgcaJhky/sb2n6ZlMGJKaDlCoq4V8+d53JuSptqjmRbAdlJ2dcNGfmy8Qs3R2Hj tdBV8WQMHiBREnEmv3M11lFZYt3jjVno3PtkR2P46cYvU9C+9abY+MabnF39OkRFWf3QgC/O/rR NPJY8 X-Google-Smtp-Source: AGHT+IEDJ6Qm0Ur3ac3Ih5jAsMWLAgYjL99/0S8sUsnqlAT4/rYCzrAkgc1FBvTgHlungYhO6iFY8w== X-Received: by 2002:a05:600c:4f90:b0:44a:b468:87b1 with SMTP id 5b1f17b1804b1-45201506dd3mr20374865e9.4.1749195736011; Fri, 06 Jun 2025 00:42:16 -0700 (PDT) Received: from [192.168.1.221] ([5.30.189.74]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4526e056138sm12622585e9.5.2025.06.06.00.42.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 06 Jun 2025 00:42:15 -0700 (PDT) Message-ID: Date: Fri, 6 Jun 2025 10:42:11 +0300 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] dmaengine: mediatek: Fix a flag reuse error in mtk_cqdma_tx_status() To: Qiu-ji Chen , sean.wang@mediatek.com, vkoul@kernel.org, matthias.bgg@gmail.com, angelogioacchino.delregno@collabora.com Cc: dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, baijiaju1990@gmail.com, stable@vger.kernel.org, kernel test robot References: <20250606071709.4738-1-chenqiuji666@gmail.com> Content-Language: en-US From: Eugen Hristev In-Reply-To: <20250606071709.4738-1-chenqiuji666@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250606_004217_989170_D2B3B212 X-CRM114-Status: GOOD ( 13.70 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On 6/6/25 10:17, Qiu-ji Chen wrote: > Fixed a flag reuse bug in the mtk_cqdma_tx_status() function. > > Fixes: 157ae5ffd76a ("dmaengine: mediatek: Fix a possible deadlock error in mtk_cqdma_tx_status()") > Cc: stable@vger.kernel.org > Reported-by: kernel test robot > Closes: https://lore.kernel.org/oe-kbuild-all/202505270641.MStzJUfU-lkp@intel.com/ > Signed-off-by: Qiu-ji Chen > --- > drivers/dma/mediatek/mtk-cqdma.c | 11 ++++++----- > 1 file changed, 6 insertions(+), 5 deletions(-) > > diff --git a/drivers/dma/mediatek/mtk-cqdma.c b/drivers/dma/mediatek/mtk-cqdma.c > index 47c8adfdc155..f7b870d2ca90 100644 > --- a/drivers/dma/mediatek/mtk-cqdma.c > +++ b/drivers/dma/mediatek/mtk-cqdma.c > @@ -441,18 +441,19 @@ static enum dma_status mtk_cqdma_tx_status(struct dma_chan *c, > struct mtk_cqdma_vdesc *cvd; > struct virt_dma_desc *vd; > enum dma_status ret; > - unsigned long flags; > + unsigned long pc_flags; > + unsigned long vc_flags; > size_t bytes = 0; > > ret = dma_cookie_status(c, cookie, txstate); > if (ret == DMA_COMPLETE || !txstate) > return ret; > > - spin_lock_irqsave(&cvc->pc->lock, flags); > - spin_lock_irqsave(&cvc->vc.lock, flags); > + spin_lock_irqsave(&cvc->pc->lock, pc_flags); > + spin_lock_irqsave(&cvc->vc.lock, vc_flags); > vd = mtk_cqdma_find_active_desc(c, cookie); > - spin_unlock_irqrestore(&cvc->vc.lock, flags); > - spin_unlock_irqrestore(&cvc->pc->lock, flags); > + spin_unlock_irqrestore(&cvc->vc.lock, vc_flags); > + spin_unlock_irqrestore(&cvc->pc->lock, pc_flags); > > if (vd) { > cvd = to_cqdma_vdesc(vd); If the first spin_lock_irqsave already saved the irq flags and disabled them, would it be meaningful to actually use a simple spin_lock for the second lock ? Or rather spin_lock_nested since there is a second nested lock taken ? Eugen