From patchwork Mon Jul 6 03:17:21 2026 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hongling Zeng X-Patchwork-Id: 2573 Return-Path: X-Original-To: noreply@patchwork.local Delivered-To: noreply@patchwork.local Received: from sea.lore.kernel.org (sea.lore.kernel.org [172.234.253.10]) by mxe881.netcup.net (Postfix) with ESMTPS id C248E1C00CB for ; Mon, 6 Jul 2026 05:17:35 +0200 (CEST) Authentication-Results: mxe881; spf=pass (sender IP is 172.234.253.10) smtp.mailfrom=linux-sunxi+bounces-24190-noreply=patchwork.local@lists.linux.dev smtp.helo=sea.lore.kernel.org Received-SPF: pass (mxe881: domain of lists.linux.dev designates 172.234.253.10 as permitted sender) client-ip=172.234.253.10; envelope-from=linux-sunxi+bounces-24190-noreply=patchwork.local@lists.linux.dev; helo=sea.lore.kernel.org; Received: from smtp.subspace.kernel.org (conduit.subspace.kernel.org [100.90.174.1]) by sea.lore.kernel.org (Postfix) with ESMTP id 8975C300577E for ; Mon, 6 Jul 2026 03:17:33 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id F3DFA2E0938; Mon, 6 Jul 2026 03:17:32 +0000 (UTC) X-Original-To: linux-sunxi@lists.linux.dev Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 28151355F5F for ; Mon, 6 Jul 2026 03:17:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=124.126.103.232 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783307852; cv=none; b=brrEtjtlJHWte8a/0bekU0g2PuabjNoAKH4sV4LAAO6/L19B5SgERGpNt0Q8Kl+dwIy16D1FkpDiJpxWpNXWpDDw9MR/gYOhIBPx8tVEPf9ioAnAd0KxL7SeduA1CTCh/ykwXyNWIu3Avyb8HiY0IFnIsNsr4ZE6PyaQ6etLqd4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783307852; c=relaxed/simple; bh=hJFYERrq9ysnSX4Idrn+S2/hZq8iIzdh3p+3w4JhzHA=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=V+7brsXrcVMKys/ltBrB2TPiMVAeXG2eq9vbC5L2NuEZIETaJy7odP6QTweZGAhVFbG2ZZRb1sThrByWun0WpuXquro8BpwWbqw5w3lH0VlV4BpwSWoIH3av0QsYz/W483JcgcmUMHXFaNmVhbGN5L4RygsQDBN+oBVLhPlesU4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn; spf=pass smtp.mailfrom=kylinos.cn; arc=none smtp.client-ip=124.126.103.232 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kylinos.cn X-UUID: 361154e678e911f1aa26b74ffac11d73-20260706 X-CID-CACHE: Type:Local,Time:202607061103+08,HitQuantity:1 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.12,REQID:6e982504-d7ca-45e5-a725-04a7d47906b9,IP:0,U RL:0,TC:0,Content:-25,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTIO N:release,TS:-25 X-CID-META: VersionHash:e7bac3a,CLOUDID:8be11dd4efe86fb9ab476a1e2276960f,BulkI D:nil,BulkQuantity:0,Recheck:0,SF:102|850|865|898,TC:nil,Content:0|15|50,E DM:-3,IP:nil,URL:0,File:nil,RT:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA :0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: 361154e678e911f1aa26b74ffac11d73-20260706 X-User: zenghongling@kylinos.cn Received: from localhost.localdomain [(10.44.16.150)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA with TLSv1.3 TLS_AES_256_GCM_SHA384 256/256) with ESMTP id 424335274; Mon, 06 Jul 2026 11:17:25 +0800 From: Hongling Zeng To: vkoul@kernel.org, Frank.Li@kernel.org, wens@kernel.org, jernej.skrabec@gmail.com, samuel@sholland.org, mripard@kernel.org, arnd@arndb.de Cc: dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev, linux-kernel@vger.kernel.org, zhongling0719@126.com, Hongling Zeng , stable@vger.kernel.org Subject: [PATCH v2] dmaengine: sun6i: Fix potential deadlock on sdev->lock Date: Mon, 6 Jul 2026 11:17:21 +0800 Message-Id: <20260706031721.24415-1-zenghongling@kylinos.cn> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-sunxi@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MORS-Enabled: yes X-MORS-DOMAIN: patchwork.local X-MORS-HOSTING: hosting172546 X-MORS-USER: hosting172546 X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= sun6i_dma_terminate_all() and sun6i_dma_pause() acquire sdev->lock with plain spin_lock() from process context. If a DMA interrupt fires on the same CPU while the lock is held, the interrupt handler schedules sun6i_dma_tasklet(), which runs in softirq context and attempts to acquire the same lock with spin_lock_irq(), causing a deadlock. Fix by using spin_lock_irq() to disable interrupts while holding sdev->lock, consistent with other call sites. Fixes: ba489fd46ab6 ("dmaengine: sun6i: Add support for Allwinner A31 DMA controller") Cc: stable@vger.kernel.org Signed-off-by: Hongling Zeng --- Change in v2: -Fix by using spin_lock_irqsave() and spin_unlock_irqrestore() to disable interrupts while holding sdev->lock and properly save/restore interrupt state. --- drivers/dma/sun6i-dma.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c index a9a254dbf8cb..a6487971ad09 100644 --- a/drivers/dma/sun6i-dma.c +++ b/drivers/dma/sun6i-dma.c @@ -891,6 +891,7 @@ static int sun6i_dma_pause(struct dma_chan *chan) struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); struct sun6i_vchan *vchan = to_sun6i_vchan(chan); struct sun6i_pchan *pchan = vchan->phy; + unsigned long flags; dev_dbg(chan2dev(chan), "vchan %p: pause\n", &vchan->vc); @@ -898,9 +899,9 @@ static int sun6i_dma_pause(struct dma_chan *chan) writel(DMA_CHAN_PAUSE_PAUSE, pchan->base + DMA_CHAN_PAUSE); } else { - spin_lock(&sdev->lock); + spin_lock_irqsave(&sdev->lock, flags); list_del_init(&vchan->node); - spin_unlock(&sdev->lock); + spin_unlock_irqrestore(&sdev->lock, flags); } return 0; @@ -939,9 +940,9 @@ static int sun6i_dma_terminate_all(struct dma_chan *chan) unsigned long flags; LIST_HEAD(head); - spin_lock(&sdev->lock); + spin_lock_irqsave(&sdev->lock, flags); list_del_init(&vchan->node); - spin_unlock(&sdev->lock); + spin_unlock_irqrestore(&sdev->lock, flags); spin_lock_irqsave(&vchan->vc.lock, flags);