Date: Fri, 7 Oct 2016 08:11:36 -0300
From: Mauro Carvalho Chehab <mchehab@s-opensource.com>
To: Jiri Kosina <jikos@kernel.org>
Cc: =?UTF-8?B?SsO2cmc=?= Otte <jrg.otte@gmail.com>,
        Johannes Stezenbach <js@linuxtv.org>,
        Patrick Boettcher <patrick.boettcher@posteo.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Andy Lutomirski <luto@kernel.org>,
        Michael Krufky <mkrufky@linuxtv.org>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Linux Media Mailing List <linux-media@vger.kernel.org>
Subject: Re: Problem with VMAP_STACK=y
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Em Fri, 7 Oct 2016 09:52:56 +0200 (CEST)
Jiri Kosina <jikos@kernel.org> escreveu:

> On Thu, 6 Oct 2016, Mauro Carvalho Chehab wrote:
> 
> > I can't see any other obvious error on the conversion. You could try to 
> > enable debug options at DVB core/dvb-usb and/or add some printk's to the 
> > driver and see what's happening.
> 
> Mauro, also please don't forget that there are many more places in 
> drivers/media that still perform DMA on stack, and so have to be fixed for 
> 4.9 (as VMAP_STACK makes that to be immediately visible problem even on 
> x86_64, which it wasn't the case before).

Yes, I'm aware of that. I'm doing the conversion of drivers under dvb-usb,
at:
	https://git.linuxtv.org/mchehab/experimental.git/log/?h=media_dmastack_fixes

I'll be sending the patches to the ML after ready.

I'll then take a look on other USB drivers that use the stack. I guess
the non-USB media drivers are safe from this issue.

Thanks,
Mauro