From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: [PATCH v3 03/10] iommu/sva: Manage process address spaces Date: Wed, 26 Sep 2018 14:45:27 +0200 Message-ID: <20180926124527.GD18287@8bytes.org> References: <20180920170046.20154-1-jean-philippe.brucker@arm.com> <20180920170046.20154-4-jean-philippe.brucker@arm.com> <09933fce-b959-32e1-b1f3-0d4389abf735@linux.intel.com> <20180925132627.vbdotr23o7lqrmnd@8bytes.org> <754d495d-d016-f42f-5682-ba4a75a618e0@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <754d495d-d016-f42f-5682-ba4a75a618e0-5wv7dgnIgG8@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Jean-Philippe Brucker Cc: "kevin.tian-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org" , "ashok.raj-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org" , "linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "ilias.apalodimas-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org" , Will Deacon , "alex.williamson-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org" , "okaya-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org" , "iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org" , "liguozhu-C8/M+/jPZTeaMJb+Lgu22Q@public.gmane.org" , Robin Murphy , "christian.koenig-5C7GfCeVMHo@public.gmane.org" List-Id: iommu@lists.linux-foundation.org On Wed, Sep 26, 2018 at 11:20:34AM +0100, Jean-Philippe Brucker wrote: > Yes, at the moment it's difficult to guess what device drivers will > want, but I can imagine some driver offering SVA to userspace, while > keeping a few PASIDs for themselves to map kernel memory. Or create mdev > devices for virtualization while also allowing bare-metal SVA. So I > think we should aim at enabling these use-cases in parallel, even if it > doesn't necessarily need to be possible right now. Yeah okay, but allowing these use-cases in parallel basically disallows giving any guest control over a device's pasid-table, no? I am just asking because I want to make up my mind about the necessary extensions to the IOMMU-API. Regards, Joerg