From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail.ukfsn.org ([77.75.108.3]:54104 "EHLO mail.ukfsn.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755938Ab2BCLEb (ORCPT ); Fri, 3 Feb 2012 06:04:31 -0500 Message-ID: <4F2BBF3E.1030809@ukfsn.org> Date: Fri, 03 Feb 2012 11:04:30 +0000 From: Andy Furniss MIME-Version: 1.0 To: gennarone@gmail.com CC: linux-media@vger.kernel.org Subject: Re: PCTV 290e page allocation failure References: <4F2AC7BF.4040006@ukfsn.org> <4F2ADDCB.4060200@gmail.com> <4F2AEA81.90506@ukfsn.org> <4F2B184F.4030709@gmail.com> In-Reply-To: <4F2B184F.4030709@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Gianluca Gennari wrote: >> What kernel are you using? >> >> I see someone else had problems with> 3.0, I've got a 3.08 built on >> this box, I'll try it out when I get a chance to reboot, though it took >> a couple of days to show on my current kernel. >> >> Andy. >> > > Hi Andy, > I'm running 3.1.0 but I back-ported a few patches from 3.2.0 to update > the PCTV 290e driver to the latest version. > In the past months I run 2.6.18/2.6.31/3.0.3 before buying the PCTV > 290e, but I never had this problem with the old dvb-usb stick. Hi, I tried my 3.08 but changed back as I was getting corrupted HD streams. Maybe because the config for that kernel was no SMP and no preemption. I did do lots of cat /proc/buddyinfo and echo m > /proc/sysrq-trigger and it looks like having lots of files open is my problem - but I didn't run long enough to provoke a fail. It seems even if the above commands show no continuous DMA above 16k when you actually try and use it the kernel defrags so it works and the output will then show larger chunks available for a while. When I had 2xPCI running it was mainly on 2.6.26 and I was also using legacy IDE - I wonder if that behaved differently with 00s of open files - or maybe it's just that PCIs (remaining one is cx88) just don't ask for big 64k DMA buffers.