linux-kernel - Re: [PATCH v2 2/7] bus: Introduce firewall controller framework

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 14 Feb 2020 16:40:51 -0500
From:   Greg KH <gregkh@...uxfoundation.org>
To:     Linus Walleij <linus.walleij@...aro.org>
Cc:     Stephen Rothwell <sfr@...b.auug.org.au>,
        Grant Likely <grant.likely@....com>,
        Benjamin GAIGNARD <benjamin.gaignard@...com>,
        "robh@...nel.org" <robh@...nel.org>,
        Loic PALLARDY <loic.pallardy@...com>,
        "arnd@...db.de" <arnd@...db.de>,
        "devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
        "system-dt@...ts.openampproject.org" 
        <system-dt@...ts.openampproject.org>,
        "s.hauer@...gutronix.de" <s.hauer@...gutronix.de>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "lkml@...ux.net" <lkml@...ux.net>,
        "linux-imx@....com" <linux-imx@....com>,
        "kernel@...gutronix.de" <kernel@...gutronix.de>,
        "sudeep.holla@....com" <sudeep.holla@....com>,
        "fabio.estevam@....com" <fabio.estevam@....com>,
        "stefano.stabellini@...inx.com" <stefano.stabellini@...inx.com>,
        "shawnguo@...nel.org" <shawnguo@...nel.org>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH v2 2/7] bus: Introduce firewall controller framework

On Fri, Feb 14, 2020 at 05:05:07PM +0100, Linus Walleij wrote:
> On Fri, Jan 31, 2020 at 10:06 AM Greg KH <gregkh@...uxfoundation.org> wrote:
> 
> > Why do people want to abuse the platform bus so much?  If a device is on
> > a bus that can have such a controller, then it is on a real bus, use it!
> 
> I'm not saying it is a good thing, but the reason why it is (ab)used so
> much can be found in:
> drivers/of/platform.c
> 
> TL;DR: struct platform_device is the Device McDeviceFace and
> platform bus the Bus McBusFace used by the device tree parser since
> it is slightly to completely unaware of what devices it is actually
> spawning.

<snip>

Yeah, great explaination, and I understand.  DT stuff really is ok to be
on a platform bus, as that's what almost all of them are.

But, when you try to start messing around with things like this
"firewall" says it is doing, it's then obvious that this really isn't a
DT like thing, but rather you do have a bus involved with a controller
so that should be used instead.

Or just filter away the DT stuff so that the kernel never even sees
those devices, which might just be simplest :)

thanks,

greg k-h