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 2094CC83006 for ; Wed, 29 Apr 2020 15:29:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EDCA5206D9 for ; Wed, 29 Apr 2020 15:29:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="FfliAmS4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726854AbgD2P3B (ORCPT ); Wed, 29 Apr 2020 11:29:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42476 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726519AbgD2P3A (ORCPT ); Wed, 29 Apr 2020 11:29:00 -0400 Received: from mail-wm1-x342.google.com (mail-wm1-x342.google.com [IPv6:2a00:1450:4864:20::342]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4414EC03C1AD; Wed, 29 Apr 2020 08:29:00 -0700 (PDT) Received: by mail-wm1-x342.google.com with SMTP id h4so2507102wmb.4; Wed, 29 Apr 2020 08:29:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=zpYTppJl8xITcXNjFG3mhRJQ4BqNT4t6jdmu0jX6CAo=; b=FfliAmS4HJ/Z/WwJPni1VOzF54pCWLK3EY2kn71GM/NZp04TRYN2yispFK26xhVt/N gh+KDbou36najGd579iZnZTcSPqKelQPmlTwCADD58HJx1KZvZZ3doQ27CNYGxbP3FtQ GqOSQKrdoft0oPf7Y7LBeknYJRC2fKcImjjfRD6Mql+ogL0MzmkIVWNngnfU4adlBoUM C2zPOmrdHHiPkQfORd+i3xQBGl6X6f+bEMHaAcetE7pFylDfb58NkF1BmRWgIB9iOclc UTKt+L+r+/Bh0QRxn2yDMoBAQkr0u5W792w5audiiouP1ufApBFdi/pZaH6zP/zfQkeT lWmg== 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:mime-version :content-transfer-encoding; bh=zpYTppJl8xITcXNjFG3mhRJQ4BqNT4t6jdmu0jX6CAo=; b=HrecTguI2A/3k4NJthEklzjJ10Munv51K2q9TAOOhKMnWwILCuDtBbQDm3cmYX75Fm PkzykVfMMhWhygW/6d51FQzt2qJQoHib7T8qNlvE/N9/GDXeq56u31ufh1dYga2n6FSG Chftpu7NfqtVG4rWUr2H6OO0tU89xL6/2zynxx9m/NQxua+B5mvLEbCH2wYGH6EKDT0h mQRF29GvmyI9SyECbYHtnt6KgwYqknZVqbEuwviIDmQfXZ55cXJqPR3QiglLZuhdTMou ZWzv81JHMoE6QLsqe59hHR5DidTlnOrCEINv4WS1/Og2JiYpL9nxuzBakZ5vuIk0wQQL afdw== X-Gm-Message-State: AGi0PuZfMZGik66fQrzYBToBf8f4MVi3/Riysy7mQYKuxd2PH2f7B0Lx YPnBlNuXVEQmRm44s6tCXjU= X-Google-Smtp-Source: APiQypKEzDUYyz/kdE+s5u7ch9nl4qGxuitJCLUJD55ILxS1BoEeyZEEWjjUjJ/RuSPbm1mVdyxXag== X-Received: by 2002:a1c:5403:: with SMTP id i3mr4144622wmb.10.1588174138782; Wed, 29 Apr 2020 08:28:58 -0700 (PDT) Received: from localhost.localdomain ([188.24.130.199]) by smtp.gmail.com with ESMTPSA id 62sm21775642wro.65.2020.04.29.08.28.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Apr 2020 08:28:58 -0700 (PDT) From: Cristian Ciocaltea To: Manivannan Sadhasivam , =?UTF-8?q?Andreas=20F=C3=A4rber?= Cc: Vinod Koul , Dan Williams , dmaengine@vger.kernel.org, linux-actions@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 1/1] dma: actions: Fix lockdep splat for owl-dma Date: Wed, 29 Apr 2020 18:28:56 +0300 Message-Id: <2f3e665270b8d170ea19cc66c6f0c68bf8fe97ff.1588173497.git.cristian.ciocaltea@gmail.com> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When the kernel is built with lockdep support and the owl-dma driver is used, the following message is shown: [ 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