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=-4.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no 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 5544DC11D32 for ; Mon, 24 Feb 2020 16:30:36 +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 2BA942080D for ; Mon, 24 Feb 2020 16:30:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="gdPuLwCj"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="WOuUHmVu" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2BA942080D 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=bq/gxs1jq6SlR08Q7vVMu2GpAMRGQOuGfvjxrTBS+Qk=; b=gdPuLwCjT6uAcg qF4dlsivZZLw+R25wzqENJ3HLk/SSFTO3l2b4+qK6N8A0T7cWehQe8DD+8wNTQerb2Bhd7I2oIUYC eC7zS685T0faXbEUmds7AlFa7HfOYQKSPZOavKYLgoEVzmlcDpIP6am0yacVZHtbH7cUPeB5NmHw/ OXcbPIwUYLWGCt3AodmbwnM3b41UC627PHgcMZx31Dp7liG8uykgIV75ucmmpNV5xQWoSIj6scDj6 cUKR3TUoBBcg/SlhBztpFLN3VpAGXfQOKKYQixCQ6roHthiVlgaQX2QZ8kvCipW/yq3uDwmXisXMC NBOr6jKNkNrqrnwzOSPA==; 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 1j6Gct-00034W-Of; Mon, 24 Feb 2020 16:30:35 +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 1j6Gcr-00033C-26 for linux-arm-kernel@lists.infradead.org; Mon, 24 Feb 2020 16:30:34 +0000 Received: from localhost (unknown [122.182.199.233]) (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 3A71C2080D; Mon, 24 Feb 2020 16:30:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582561832; bh=bWGcTJqlEjn5g6u4zNf52Tgw+7hzPPuuxO1718WofvA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=WOuUHmVuhUlHGACL8h761/MJUQrCsP7cItrYsH/EPFN5/CWTX/WD7k/gQIcfsYprC THqF5EMHw5Z/GPl8lOWySVsfqFUx1EDyJ8ughC2WyxFvU0X8Q70HSqqBtxGuaUOMGD LqdhIX6GEGVPCDYY4X0NXiFUHLN8GllBbgKZTpDA= Date: Mon, 24 Feb 2020 22:00:25 +0530 From: Vinod Koul To: Linus Walleij Subject: Re: [PATCH] dmaengine: coh901318: Fix a double lock bug in dma_tc_handle() Message-ID: <20200224163025.GX2618@vkoul-mobl> References: <20200217144050.3i4ymbytogod4ijn@kili.mountain> <20200219091754.GE2618@vkoul-mobl> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200224_083033_122603_9BB55965 X-CRM114-Status: GOOD ( 18.95 ) 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: kernel-janitors@vger.kernel.org, Jia-Ju Bai , Geert Uytterhoeven , Linux ARM , dmaengine , Dan Williams , Dan Carpenter 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 On 21-02-20, 15:50, Linus Walleij wrote: > On Wed, Feb 19, 2020 at 10:17 AM Vinod Koul wrote: > > On 17-02-20, 23:24, Geert Uytterhoeven wrote: > > > On Mon, Feb 17, 2020 at 3:41 PM Dan Carpenter wrote: > > > > The caller is already holding the lock so this will deadlock. > > > > > > > > Fixes: 0b58828c923e ("DMAENGINE: COH 901 318 remove irq counting") > > > > Signed-off-by: Dan Carpenter > > > > --- > > > > This is the second double lock bug found using static analysis. The > > > > previous one was commit 627469e4445b ("dmaengine: coh901318: Fix a > > > > double-lock bug"). > > > > > > > > The fact that this has been broken for ten years suggests that no one > > > > has the hardware. > > > > > > Or this only runs CONFIG_SMP=n kernels? > > > This seems to be used in arch/arm/boot/dts/ste-u300.dts only, and > > > CONFIG_ARCH_U300 is a ARCH_MULTI_V5 platform, which looks like > > > it doesn't support SMP? > > > > Should we drop the driver then..? > > I still have the hardware and it still works if that is the question :D Thanks for confirming :) > > And yeah it only has one CPU, but still has a DMA engine. > > The patch is fine to apply because it fixes a bug, should the same > hardware block be used on SMP. Applied now. -- ~Vinod _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel