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=-7.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS 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 C2A53C3A5A9 for ; Sat, 2 May 2020 12:23:55 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 890C42072E for ; Sat, 2 May 2020 12:23:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="fbL20co4"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="JpJkJ9V2" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 890C42072E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=HLKyKnLJSHtl7BzuIOiWWfBxH/UrRqnaUkcdvT6v8l4=; b=fbL20co4DKIM+d ys0u++lgGFqG8XXNRnOBiRd4y23cPt2caGHA7FVoXGsjSgyynV/xFtdiigLXz0F7zAwXJGVCvWuR4 jFFPq0eFc4W+60D9HDj8/3OBFJR1EhNJK4DBZqnzTIH/6GQJs4CxI/CybUNriFCTMMYO2q+EUxzIS xsazalaLph/BFeqDCb1f+aAuQ8qP4yxhGfpUmcK2XRdkHZgITAuXt6T+yAfBgFSFJtvVma6Hym+md VwAxO6U1Qxa+eQ1Va0O2HnJuyX+M8+nZRDBy2Xf1hQATOxjfLXKFnsJYfsO3947NH0BvdvQbJJmFc tD8Ot4t8RL6TWkNwoupQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jUrBP-0006fO-G8; Sat, 02 May 2020 12:23:51 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jUrBM-0006dK-K0; Sat, 02 May 2020 12:23:50 +0000 Received: from localhost (unknown [117.99.89.89]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 84B612072E; Sat, 2 May 2020 12:23:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588422225; bh=VFZRfbxaSvB4UZ1zviOZTlVRbHiO20UoTo/B+qSaaG4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=JpJkJ9V2yIOYst2+CnADV6vZYbBSsji5p95E18XUDniryQPcpKFxZB5djNDn5HRTZ Q8T87KG0xlmNwr+jnKYaX+rWSjBxosCZnJVea4ZTG0FVprle9Ef/q0v+aarIWkqcuf aqSex9O5rdCoke0a5TWf4vvQkTreuuttfb06KRh0= Date: Sat, 2 May 2020 17:53:33 +0530 From: Vinod Koul To: Cristian Ciocaltea Subject: Re: [PATCH v3 1/1] dma: actions: Fix lockdep splat for owl-dma Message-ID: <20200502122333.GA1375924@vkoul-mobl> References: <2f3e665270b8d170ea19cc66c6f0c68bf8fe97ff.1588173497.git.cristian.ciocaltea@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <2f3e665270b8d170ea19cc66c6f0c68bf8fe97ff.1588173497.git.cristian.ciocaltea@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200502_052348_706704_A9F97183 X-CRM114-Status: GOOD ( 25.00 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-actions@lists.infradead.org, linux-kernel@vger.kernel.org, Manivannan Sadhasivam , dmaengine@vger.kernel.org, Dan Williams , Andreas =?iso-8859-1?Q?F=E4rber?= , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Cristian, On 29-04-20, 18:28, Cristian Ciocaltea wrote: > When the kernel is built with lockdep support and the owl-dma driver is > used, the following message is shown: First the patch title needs upate, we describe the patch in the title and not the cause. So use correct lock, or use od lock might be better titles, pls revise. Second, the susbsystem is named dmaengine:... not dma:.. You can always check that by using git log on the respective file Pls do add fixes and further acks received on next iteration. > > [ 2.496939] INFO: trying to register non-static key. > [ 2.501889] the code is fine but needs lockdep annotation. > [ 2.507357] turning off the locking correctness validator. > [ 2.512834] CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.6.3+ #15 > [ 2.519084] Hardware name: Generic DT based system > [ 2.523878] Workqueue: events_freezable mmc_rescan > [ 2.528681] [<801127f0>] (unwind_backtrace) from [<8010da58>] (show_stack+0x10/0x14) > [ 2.536420] [<8010da58>] (show_stack) from [<8080fbe8>] (dump_stack+0xb4/0xe0) > [ 2.543645] [<8080fbe8>] (dump_stack) from [<8017efa4>] (register_lock_class+0x6f0/0x718) > [ 2.551816] [<8017efa4>] (register_lock_class) from [<8017b7d0>] (__lock_acquire+0x78/0x25f0) > [ 2.560330] [<8017b7d0>] (__lock_acquire) from [<8017e5e4>] (lock_acquire+0xd8/0x1f4) > [ 2.568159] [<8017e5e4>] (lock_acquire) from [<80831fb0>] (_raw_spin_lock_irqsave+0x3c/0x50) > [ 2.576589] [<80831fb0>] (_raw_spin_lock_irqsave) from [<8051b5fc>] (owl_dma_issue_pending+0xbc/0x120) > [ 2.585884] [<8051b5fc>] (owl_dma_issue_pending) from [<80668cbc>] (owl_mmc_request+0x1b0/0x390) > [ 2.594655] [<80668cbc>] (owl_mmc_request) from [<80650ce0>] (mmc_start_request+0x94/0xbc) > [ 2.602906] [<80650ce0>] (mmc_start_request) from [<80650ec0>] (mmc_wait_for_req+0x64/0xd0) > [ 2.611245] [<80650ec0>] (mmc_wait_for_req) from [<8065aa10>] (mmc_app_send_scr+0x10c/0x144) > [ 2.619669] [<8065aa10>] (mmc_app_send_scr) from [<80659b3c>] (mmc_sd_setup_card+0x4c/0x318) > [ 2.628092] [<80659b3c>] (mmc_sd_setup_card) from [<80659f0c>] (mmc_sd_init_card+0x104/0x430) > [ 2.636601] [<80659f0c>] (mmc_sd_init_card) from [<8065a3e0>] (mmc_attach_sd+0xcc/0x16c) > [ 2.644678] [<8065a3e0>] (mmc_attach_sd) from [<8065301c>] (mmc_rescan+0x3ac/0x40c) > [ 2.652332] [<8065301c>] (mmc_rescan) from [<80143244>] (process_one_work+0x2d8/0x780) > [ 2.660239] [<80143244>] (process_one_work) from [<80143730>] (worker_thread+0x44/0x598) > [ 2.668323] [<80143730>] (worker_thread) from [<8014b5f8>] (kthread+0x148/0x150) > [ 2.675708] [<8014b5f8>] (kthread) from [<801010b4>] (ret_from_fork+0x14/0x20) > [ 2.682912] Exception stack(0xee8fdfb0 to 0xee8fdff8) > [ 2.687954] dfa0: 00000000 00000000 00000000 00000000 > [ 2.696118] dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > [ 2.704277] dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 > > The obvious fix would be to use 'spin_lock_init()' on 'pchan->lock' > before attempting to call 'spin_lock_irqsave()' in 'owl_dma_get_pchan()'. > > However, according to Manivannan Sadhasivam, 'pchan->lock' was supposed > to only protect 'pchan->vchan' while 'od->lock' does a similar job in > 'owl_dma_terminate_pchan'. > > Therefore, this patch will simply substitute 'pchan->lock' with 'od->lock' > and removes the 'lock' attribute in 'owl_dma_pchan' struct. > > Signed-off-by: Cristian Ciocaltea > Reviewed-by: Manivannan Sadhasivam > --- > Changes in v3: > * Get rid of the kerneldoc comment for the removed struct attribute > * Add the Reviewed-by tag in the commit message > > Changes in v2: > * Improve the fix as suggested by Manivannan Sadhasivam: substitute > 'pchan->lock' with 'od->lock' and get rid of the 'lock' attribute in > 'owl_dma_pchan' struct > * Update the commit message to reflect the changes > > drivers/dma/owl-dma.c | 8 +++----- > 1 file changed, 3 insertions(+), 5 deletions(-) > > diff --git a/drivers/dma/owl-dma.c b/drivers/dma/owl-dma.c > index c683051257fd..66ef70b00ec0 100644 > --- a/drivers/dma/owl-dma.c > +++ b/drivers/dma/owl-dma.c > @@ -175,13 +175,11 @@ struct owl_dma_txd { > * @id: physical index to this channel > * @base: virtual memory base for the dma channel > * @vchan: the virtual channel currently being served by this physical channel > - * @lock: a lock to use when altering an instance of this struct > */ > struct owl_dma_pchan { > u32 id; > void __iomem *base; > struct owl_dma_vchan *vchan; > - spinlock_t lock; > }; > > /** > @@ -437,14 +435,14 @@ static struct owl_dma_pchan *owl_dma_get_pchan(struct owl_dma *od, > for (i = 0; i < od->nr_pchans; i++) { > pchan = &od->pchans[i]; > > - spin_lock_irqsave(&pchan->lock, flags); > + spin_lock_irqsave(&od->lock, flags); > if (!pchan->vchan) { > pchan->vchan = vchan; > - spin_unlock_irqrestore(&pchan->lock, flags); > + spin_unlock_irqrestore(&od->lock, flags); > break; > } > > - spin_unlock_irqrestore(&pchan->lock, flags); > + spin_unlock_irqrestore(&od->lock, flags); > } > > return pchan; > -- > 2.26.2 -- ~Vinod _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel