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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 34D52C2BB55 for ; Thu, 16 Apr 2020 12:13:40 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E613F20767 for ; Thu, 16 Apr 2020 12:13:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="uPEh7nQY" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E613F20767 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 84D688E00AA; Thu, 16 Apr 2020 08:13:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7FEF48E0001; Thu, 16 Apr 2020 08:13:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 713888E00AA; Thu, 16 Apr 2020 08:13:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0060.hostedemail.com [216.40.44.60]) by kanga.kvack.org (Postfix) with ESMTP id 598838E0001 for ; Thu, 16 Apr 2020 08:13:39 -0400 (EDT) Received: from smtpin12.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id D1EE95DF4 for ; Thu, 16 Apr 2020 12:13:38 +0000 (UTC) X-FDA: 76713608916.12.honey42_1fccf8d24a62b X-HE-Tag: honey42_1fccf8d24a62b X-Filterd-Recvd-Size: 3277 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf31.hostedemail.com (Postfix) with ESMTP for ; Thu, 16 Apr 2020 12:13:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=hp6+eCj2O2nxWa/wGv8G7WCsIo0VMT1PsA9CYyFBw9A=; b=uPEh7nQY1JKkhF8C0Y4y2Gmad+ 0Lh9YxbB3n3bpZKSCTfe6apdDsHEJQ8+1fnAfMJYOQ7Ql+RYgwCiCPEay95+4hAhiUPJevlzeX1fJ juawpIUiGFu5mfa45bPWKqLkW/n9s5rroA3MynnjLIq7Qat6n1jaBQx75J3NNZelUA4YrqkUuGVcz H4Y2Zaeu42mCsHRkgGXpP+lVm6OKcx1KkTmiiHaNW3oV6yz92qPAmnFt+DrohrYDUCVX35t3XPvgO I1F0/d5RJPxCiBLE4f1cc1WmYObAzPqAFWgla4SAq3SvBWHFY87AaCOmi+Lt3b0XoTejUhCJEzA40 t2381FKw==; Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jP3Oe-0002ua-05; Thu, 16 Apr 2020 12:13:32 +0000 Date: Thu, 16 Apr 2020 05:13:31 -0700 From: Christoph Hellwig To: Jean-Philippe Brucker Cc: Christoph Hellwig , iommu@lists.linux-foundation.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org, linux-mm@kvack.org, joro@8bytes.org, catalin.marinas@arm.com, will@kernel.org, robin.murphy@arm.com, kevin.tian@intel.com, baolu.lu@linux.intel.com, Jonathan.Cameron@huawei.com, jacob.jun.pan@linux.intel.com, christian.koenig@amd.com, zhangfei.gao@linaro.org, jgg@ziepe.ca, xuzaibo@huawei.com Subject: Re: [PATCH v5 02/25] iommu/sva: Manage process address spaces Message-ID: <20200416121331.GA18661@infradead.org> References: <20200414170252.714402-1-jean-philippe@linaro.org> <20200414170252.714402-3-jean-philippe@linaro.org> <20200416072852.GA32000@infradead.org> <20200416085402.GB1286150@myrica> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200416085402.GB1286150@myrica> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Apr 16, 2020 at 10:54:02AM +0200, Jean-Philippe Brucker wrote: > On Thu, Apr 16, 2020 at 12:28:52AM -0700, Christoph Hellwig wrote: > > > + rcu_read_lock(); > > > + hlist_for_each_entry_rcu(bond, &io_mm->devices, mm_node) > > > + io_mm->ops->invalidate(bond->sva.dev, io_mm->pasid, io_mm->ctx, > > > + start, end - start); > > > + rcu_read_unlock(); > > > +} > > > > What is the reason that the devices don't register their own notifiers? > > This kinds of multiplexing is always rather messy, and you do it for > > all the methods. > > This sends TLB and ATC invalidations through the IOMMU, it doesn't go > through device drivers I don't think we mean the same thing, probably because of my rather imprecise use of the word device. What I mean is that the mmu_notifier should not be embedded into the io_mm structure (whch btw, seems to have a way to generic name, just like all other io_* prefixed names), but instead into the iommu_bond structure. That avoid the whole multiplexing layer.