From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: Nouveau on dom0 Date: Thu, 25 Feb 2010 12:44:11 -0500 Message-ID: <20100225174411.GA13270@phenom.dumpdata.com> References: <20100225125552.GC9040@phenom.dumpdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Arvind R Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On Thu, Feb 25, 2010 at 09:01:48AM -0800, Arvind R wrote: > On Thu, Feb 25, 2010 at 6:25 PM, Konrad Rzeszutek Wilk > wrote: > > On Thu, Feb 25, 2010 at 02:16:07PM +0530, Arvind R wrote: > >> Hi all, > >> I merged the drm-tree from 2.6.33-rc8 into jeremy's 2.6.31.6 master and > ======= snip ======= > > is not. Would it be possible to trace down who allocates that *chan? You > > say it is 'PRAMIN' - is that allocated via pci_alloc_* call? > > > > Or is the address retrieved from an ioctl call made in user-space? > Both true, I guess. > > chan is GFP_KERNEL allocated. My current understanding is that > chan->cur, at the end of a lot of initialization, points to specific > areas of card > memory which forms a command ring. What gets written is 32-bits which > encode pointers to contexts and methods already associated with that > specific channel. Each of possibly many channels have their own independent > Command FIFOs (RINGS) and associations. > > So, there must be a mmap call somewhere to map the area to user-space > for that problem write to work on non-Xen boots. Will try track down some more > and post. With mmaps and PCIGARTs - it will be some hunt! You might want to look also at the source code of the nouveu X driver. I remember looking at the radeon one, where it made an drmScatterMap call, saved it, and then later submitted that address via an ioctl call to the drm_radeon driver which used it as a ring buffer. Took a bit of hoping around to find who allocated it in the first place. > > >> another testing domU without devel-packages. > > > > You lost me here. Don't you mean Dom0? > > > Let's say virtual appliances - for which one needs dom0! Ah yes.