Received: by 2002:a25:8b12:0:0:0:0:0 with SMTP id i18csp2194241ybl; Thu, 15 Aug 2019 08:01:19 -0700 (PDT) X-Google-Smtp-Source: APXvYqzqozDq6ZIZW/xjYJfwUjCm4JoRGNF4e2qDzub6uOINpdCCQTP2BMcyRXVdG+kGHmjgd/oo X-Received: by 2002:a17:90a:3266:: with SMTP id k93mr2666153pjb.46.1565881279355; Thu, 15 Aug 2019 08:01:19 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1565881279; cv=none; d=google.com; s=arc-20160816; b=rtG5Wq1IC7U3UnO2TlF+P0U3bnn7ErEXQIoIALt766H3f2/4JSNO5CUxqllomjLQgv 0TJ0dcn5XKmEwp0JKcMMvVbxxqMtNxdGmkVfU4XqY9jlNE7h44AfKzmlD8OexhErMhA4 nENBomYxiaDEHdy8gv/5XbMJkoEVwn04NlM7/hzElManNNrVKJmcxYW5Q+Te3RujWKCl Dy3GoAd6+M5fnEDsrHVxTPQ5KrBwKrwHR+5WHiHRsEIGmslBQV91AhjQkGmBkpPXbI12 94EeQy3Ql8ijg3DKTLi52Fhf8yl4s6cq/wAsSfnbhFMVmWmfcDFNDTyvfZAhizlCZ0If a2Zw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:to :from:date; bh=5k6/KSK+AGDmGc9JFtjTBJLsAlhHVzHONCQXCcx+9A0=; b=kq7GkzsUp+EH06RI0Fsx/Mgs5j0tWE6E866eCgKMgAs/c6zDOPpVOLvXFGo5T4BvB9 hgQH5cAK3K+XvfdV6lqXuGBjwyKV992HcXyQuRDDdqLMWPn7w7JV1VD9LGbQx+ENZEGV 8FsCq9GFQ6J+mN0rTqInWZeB7hzPY8GKBNK54amVm5NaUaODXuZ2hejq/sQRc+1k7ic/ /N202QqLKtdRAYD7qnMJBGoriip/qWTEpjW1K8PJrq435O4TCvoyrhomw1taE6QUT8Ux wG8wIsAttgqjMfplVwQLp8CxMrrPSXslRwlx9g/pM+Der97FqReb4xlvv8q4pnVhd/Ie fvkg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id f188si736135pfb.22.2019.08.15.08.01.02; Thu, 15 Aug 2019 08:01:19 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732325AbfHONf7 (ORCPT + 99 others); Thu, 15 Aug 2019 09:35:59 -0400 Received: from verein.lst.de ([213.95.11.211]:46778 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731194AbfHONf6 (ORCPT ); Thu, 15 Aug 2019 09:35:58 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id A750A68AFE; Thu, 15 Aug 2019 15:35:54 +0200 (CEST) Date: Thu, 15 Aug 2019 15:35:54 +0200 From: Christoph Hellwig To: Corentin Labbe , bskeggs@redhat.com, airlied@linux.ie, hch@lst.de, m.szyprowski@samsung.com, robin.murphy@arm.com, dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org Subject: Re: DMA-API: cacheline tracking ENOMEM, dma-debug disabled due to nouveau ? Message-ID: <20190815133554.GE12036@lst.de> References: <20190814145033.GA11190@Red> <20190814174927.GT7444@phenom.ffwll.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190814174927.GT7444@phenom.ffwll.local> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 14, 2019 at 07:49:27PM +0200, Daniel Vetter wrote: > On Wed, Aug 14, 2019 at 04:50:33PM +0200, Corentin Labbe wrote: > > Hello > > > > Since lot of release (at least since 4.19), I hit the following error message: > > DMA-API: cacheline tracking ENOMEM, dma-debug disabled > > > > After hitting that, I try to check who is creating so many DMA mapping and see: > > cat /sys/kernel/debug/dma-api/dump | cut -d' ' -f2 | sort | uniq -c > > 6 ahci > > 257 e1000e > > 6 ehci-pci > > 5891 nouveau > > 24 uhci_hcd > > > > Does nouveau having this high number of DMA mapping is normal ? > > Yeah seems perfectly fine for a gpu. That is a lot and apparently overwhelm the dma-debug tracking. Robin rewrote this code in Linux 4.21 to work a little better, so I'm curious why this might have changes in 4.19, as dma-debug did not change at all there.