From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: pci adapter not working in dom0. works under plain Linux. Date: Wed, 11 Jun 2014 09:47:10 -0400 Message-ID: <20140611134710.GA17456@laptop.dumpdata.com> References: <95534be07bf54fca9c8b0dcc76f7d3aa@SIXPR04MB304.apcprd04.prod.outlook.com> <20140609165149.GF2275@laptop.dumpdata.com> <20140610130832.GC28932@laptop.dumpdata.com> <1498011152.20140610170503@eikelenboom.it> <184875056.20140611141213@eikelenboom.it> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <184875056.20140611141213@eikelenboom.it> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Sander Eikelenboom Cc: James Harper , "xen-devel@lists.xen.org" List-Id: xen-devel@lists.xenproject.org On Wed, Jun 11, 2014 at 02:12:13PM +0200, Sander Eikelenboom wrote: > > Wednesday, June 11, 2014, 1:53:48 PM, you wrote: > > >> > >> > I had some preliminary patches for the V4L API to use a better > >> > DMA ops, but I fear that they are bitrotten (and I can't even > >> > find them!). But lets try first determine if the workarounds > >> > work for you. > >> > >> Were you by any means referring to this thread / patch: > >> http://lists.xen.org/archives/html/xen-devel/2012-01/msg01982.html ? > >> > > > That patch applies and compiles once you take into account some moved files. I haven't tested yet though - my mythtv box is busy recording :) > > I notice there is a 'videobuf2-dma-sg.c' file in the current tree, which I assume is a 'second generation' v4l implementation that drivers will be progressively moved over to. I can't tell if the dma implementation in there is correct, but it certainly doesn't return any hits in a grep for 32... > > A grep for the export 'vb2_dma_sg_memops' only shows up 2 drivers using it though. What's the procedure around rebasing and submitting a patch that someone else wrote? > > Yeah the conversion is going slowly .. i tried to start it for the cx25821 .. > but the problem is it's "all or nothing" you can't do it in little steps. You mean the patch I wrote that I totally forgot about until Sander awesomely found it? You can go ahead and have it come from you (aka, the author can be you). The only thing I would ask you to keep is my SOB (so it is known that it came through my hands) in the patch and maybe mention: "Rework of Konrad's initial patch" (optional). You should not treat this as a general rule though - but the yardstick I've done is - contact the author of the patch - ask them if they are OK with the patch and me reworking it. If they don't respond or are unreachable I take the ownership of the patch and start reworking. At that point I just make sure that I keep their original Copyright in the file or mention it as an SoB. > > > I think Konrad's fix is the right way to go. Someone else suggested fixing vmalloc32, which is probably still a good idea, but when most of the devices these days are probably quite happy with 64 bit addresses so sticking with the artificial 4G limit is probably a bit silly. > > I'll follow up once I've tested later tonight or tomorrow. > > > Thanks! > > > James > > >