netdev - Re: consequences of setting net_device_ops ndo_change

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]

Message-ID: <alpine.LFD.2.21.1808041326550.4126@localhost.localdomain>
Date:   Sat, 4 Aug 2018 13:32:40 -0400 (EDT)
From:   "Robert P. J. Day" <rpjday@...shcourse.ca>
To:     Stephen Hemminger <stephen@...workplumber.org>
cc:     Jiri Pirko <jiri@...nulli.us>,
        Linux kernel ntedev mailing list <netdev@...r.kernel.org>
Subject: Re: consequences of setting net_device_ops ndo_change_carrier()?

On Sat, 4 Aug 2018, Stephen Hemminger wrote:

... big snip ...

> ndo_change_carrier is not the droid your looking for.
>
> The purpose of ndo_change_carrier was for testing network devices
> (ie dummy), and also for cases like network tunnels where the
> sofrware carrier state may be controlled by a userspace daemon.
>
> Real network devices call netif_carrier_on and netif_carrier_off
> when they notice change in carrier state in hardware. Typically,
> this is when an interrupt happens.

  i had actually come to just that conclusion, as i was digging
through the code, and couldn't immediately see why setting
ndo_change_carrier() would cause a problem. in fact, to help my
admittedly painful newbie-level debugging, i started a wiki page to
track this (i document *everything* on wiki pages):

  http://crashcourse.ca/dokuwiki/doku.php?id=ndo_change_carrier

so i am reduced to concluding that the drivers in question are simply
not calling correctly the very routines you mention.

rday

-- 

========================================================================
Robert P. J. Day                                 Ottawa, Ontario, CANADA
                  http://crashcourse.ca/dokuwiki

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
========================================================================