netdev - Re: [PATCH v2 00/17] net: introduce Qualcomm IPA driver

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:   Tue, 04 Jun 2019 10:21:41 -0500
From:   Dan Williams <dcbw@...hat.com>
To:     Subash Abhinov Kasiviswanathan <subashab@...eaurora.org>
Cc:     Alex Elder <elder@...aro.org>, Arnd Bergmann <arnd@...db.de>,
        David Miller <davem@...emloft.net>,
        Bjorn Andersson <bjorn.andersson@...aro.org>,
        Ilias Apalodimas <ilias.apalodimas@...aro.org>,
        evgreen@...omium.org, Ben Chan <benchan@...gle.com>,
        Eric Caruso <ejcaruso@...gle.com>, cpratapa@...eaurora.org,
        syadagir@...eaurora.org, abhishek.esse@...il.com,
        Networking <netdev@...r.kernel.org>,
        DTML <devicetree@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        linux-soc@...r.kernel.org,
        Linux ARM <linux-arm-kernel@...ts.infradead.org>,
        linux-arm-msm@...r.kernel.org
Subject: Re: [PATCH v2 00/17] net: introduce Qualcomm IPA driver

On Mon, 2019-06-03 at 13:04 -0600, Subash Abhinov Kasiviswanathan
wrote:
> > > I can't (or won't) comment right now on whether IPA needs its own
> > > netdev for rmnet to use.  The IPA endpoints used for the modem
> > > network interfaces are enabled when the netdev is opened and
> > > disabled when closed.  Outside of that, TX and RX are pretty
> > > much immediately passed through to the layer below or above.
> > > IPA currently has no other net device operations.
> > 
> > I don't really have issues with the patchset underneath the netdev
> > layer. I'm interested in how the various bits present themselves to
> > userspace, which is why I am trying to tie this in with Johannes'
> > conversation about WWAN devices, netdevs, channels, and how the
> > various
> > drivers present API for creating data channels that map to
> > different
> > modem contexts.
> > 
> > So let me rephrase. If the control plane has set up the default
> > context
> > and sent a QMI Start Network message (or the network attached the
> > default one) and the resulting IP details are applied to the IPA
> > netdev
> > can things just start sending data? Or do we need to create an
> > rmnet on
> > top to get that working?
> > 
> > Dan
> 
> Hi Dan
> 
> All data from the hardware will have the MAP headers.
> We still need to create rmnet devs over the IPA netdev and use it
> for 
> the
> data path.
> The IPA netdev will pass on the packets which it receives from the 
> hardware
> and queue it to network stack where it will be intercepted by the
> rmnet rx handler.

Ok, so IPA only needs a netdev so that rmnet has something to
send/receive packets to/from? This gets even closer to the discussion
in "cellular modem driver APIs - take 2" from last week.

Dan