Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754552AbcJEPVs (ORCPT ); Wed, 5 Oct 2016 11:21:48 -0400 Received: from mail-ua0-f175.google.com ([209.85.217.175]:33125 "EHLO mail-ua0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754254AbcJEPVq (ORCPT ); Wed, 5 Oct 2016 11:21:46 -0400 MIME-Version: 1.0 In-Reply-To: <20161005060450.1b0f2152@vento.lan> References: <20161005093417.6e82bd97@vdr> <20161005060450.1b0f2152@vento.lan> From: =?UTF-8?Q?J=C3=B6rg_Otte?= Date: Wed, 5 Oct 2016 17:21:44 +0200 Message-ID: Subject: Re: Problem with VMAP_STACK=y To: Mauro Carvalho Chehab Cc: Jiri Kosina , Patrick Boettcher , Linux Kernel Mailing List , Andy Lutomirski , Michael Krufky , Mauro Carvalho Chehab , Linux Media Mailing List Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id u95FLuWG013248 Content-Length: 1515 Lines: 45 2016-10-05 11:04 GMT+02:00 Mauro Carvalho Chehab : > Em Wed, 5 Oct 2016 09:50:42 +0200 (CEST) > Jiri Kosina escreveu: > >> On Wed, 5 Oct 2016, Patrick Boettcher wrote: >> >> > > > Thanks for the quick response. >> > > > Drivers are: >> > > > dvb_core, dvb_usb, dbv_usb_cynergyT2 >> > > >> > > This dbv_usb_cynergyT2 is not from Linus' tree, is it? I don't seem >> > > to be able to find it, and the only google hit I am getting is your >> > > very mail to LKML :) >> > >> > It's a typo, it should say dvb_usb_cinergyT2. >> >> Ah, thanks. Same issues there in >> >> cinergyt2_frontend_attach() >> cinergyt2_rc_query() >> >> I think this would require more in-depth review of all the media drivers >> and having all this fixed for 4.9. It should be pretty straightforward; >> all the instances I've seen so far should be just straightforward >> conversion to kmalloc() + kfree(), as the buffer is not being embedded in >> any structure etc. > > What we're doing on most cases is to put a buffer (usually with 80 > chars for USB drivers) inside the "state" struct (on DVB drivers), > in order to avoid doing kmalloc/kfree all the times. One such patch is > changeset c4a98793a63c4. > > I'm enclosing a non-tested patch fixing it for the cinergyT2-core.c > driver. > > Thanks, > Mauro > > [PATCH] cinergyT2-core: don't do DMA on stack > Tried the cinergyT2 patch. No success. When I select a TV channel just nothing happens. There are no error messages. Jörg