From patchwork Tue Feb 22 01:58:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?RMSBdmlzIE1vc8SBbnM=?= X-Patchwork-Id: 12754417 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C525DC433EF for ; Tue, 22 Feb 2022 01:59:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229477AbiBVB7s (ORCPT ); Mon, 21 Feb 2022 20:59:48 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:49622 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231240AbiBVB7s (ORCPT ); Mon, 21 Feb 2022 20:59:48 -0500 Received: from mail-lf1-x133.google.com (mail-lf1-x133.google.com [IPv6:2a00:1450:4864:20::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CB4401EECA; Mon, 21 Feb 2022 17:59:23 -0800 (PST) Received: by mail-lf1-x133.google.com with SMTP id u20so21870034lff.2; Mon, 21 Feb 2022 17:59:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=W4e0Or5RWevHd+mvZ+oPOZ9BD4lXm7waqKeZmhpiEe8=; b=HvRx0IuZd0XT6yuS0ZZUz/89gM8iXDEjmGhF2pXnT5CWZAj9B//bSwT0Q/H1FYjUyf gyAS28/L7MKeypEo3xteO2B4W82J7OOAlKuQjEqh9qtfAq95N65BUIV/nUTuIXakhN58 MimOcmF077XqKlrqrGdYULn7rtOux4KBqKyAdvFm1ddyIzJByVDpmz8s3fu7w5SondJh Y3zEOM6grOEr5WZ3mQ33dOXWFlRJCKQH+6g+NtjryqyUAYHWypDUBr1/6z1NPxTrDiE0 ucaczRo8RgBVIp2+9JEZRFgHbP1Psmq5X50Jc6E+kUROob6Ri0Y3rn2nloQwwYVYmF5a 0zCA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=W4e0Or5RWevHd+mvZ+oPOZ9BD4lXm7waqKeZmhpiEe8=; b=ZtzK9VUoe7YL2W6M7nLrApkpJZ6lRdvtn/O+cLlQryp1A4Q+/wLtbdB1hftNhH9yRy g68q7GILrlVsVXXux/PC3dzH3yp8c9+5H67iNRGIOThP1ajs4N+aO5YTq5A6sH5OT24X I7WuMPpxv3rRU/tXkR5xsb/JtA6EDviCwOfXOxFX/R4K4P02w4RtoknCgpl6C8orEZDs kikajNI0/NTxwViQREytDPHUNuMu9s0X1mom9bnE7lwrNESXBdl51VQvhspy01f9zoXz 7JU/Gxb+ymg99Xl02RtbnLebYGY6CSahoNfbFgJdxO++7HWo7+cEzhaCgNfHgvMYqirj G2Gw== X-Gm-Message-State: AOAM533U/D265S0sSIN3hTNF2VBwRyEdM1YS3nROrrDi1Zkqp+Xf9f62 QwJDnKesIoj7VVSlgqmqow5+M/Wj/HT0YZqX X-Google-Smtp-Source: ABdhPJyxKnDiUyaEYLNQqp5Kqvel/Q6b0YfU1P6b3CMSNq+vJFwgs/wzbJJqEmkkKObqtyac0BBilA== X-Received: by 2002:a05:6512:31cf:b0:443:7eb6:3440 with SMTP id j15-20020a05651231cf00b004437eb63440mr15283210lfe.367.1645495161995; Mon, 21 Feb 2022 17:59:21 -0800 (PST) Received: from TebraArch.. ([81.198.32.225]) by smtp.gmail.com with ESMTPSA id 10sm1255051lfq.201.2022.02.21.17.59.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Feb 2022 17:59:21 -0800 (PST) From: =?utf-8?b?RMSBdmlzIE1vc8SBbnM=?= To: linux-kernel@vger.kernel.org Cc: Vinod Koul , dmaengine@vger.kernel.org, =?utf-8?b?RMSB?= =?utf-8?b?dmlzIE1vc8SBbnM=?= Subject: [PATCH] dmaengine: fix locking for dma_channel_rebalance Date: Tue, 22 Feb 2022 03:58:49 +0200 Message-Id: <20220222015849.14727-1-davispuh@gmail.com> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org dma_channel_rebalance comment says: > Must be called under dma_list_mutex We have few places where it wasn't done and could cause crashes. So invoke it only when it's under mutex. --- drivers/dma/dmaengine.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index 2cfa8458b51be..5198bdf7ee804 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -1098,7 +1098,10 @@ int dma_async_device_channel_register(struct dma_device *device, if (rc < 0) return rc; + mutex_lock(&dma_list_mutex); dma_channel_rebalance(); + mutex_unlock(&dma_list_mutex); + return 0; } EXPORT_SYMBOL_GPL(dma_async_device_channel_register); @@ -1124,7 +1127,9 @@ void dma_async_device_channel_unregister(struct dma_device *device, struct dma_chan *chan) { __dma_async_device_channel_unregister(device, chan); + mutex_lock(&dma_list_mutex); dma_channel_rebalance(); + mutex_unlock(&dma_list_mutex); } EXPORT_SYMBOL_GPL(dma_async_device_channel_unregister);