Re: [Bugme-new] [Bug 11655] New: /proc/sys/net/ipv6/conf/all/* controls don't work

Re: [Bugme-new] [Bug 11655] New: /proc/sys/net/ipv6/conf/all/* controls don't work

[Andrew Morton]

(switched to email.  Please respond via emailed reply-to-all, not via the
bugzilla web interface).

On Fri, 26 Sep 2008 19:36:55 -0700 (PDT) bugme-daemon@bugzilla.kernel.org wrote:

> http://bugzilla.kernel.org/show_bug.cgi?id=11655
> 
>            Summary: /proc/sys/net/ipv6/conf/all/* controls don't work
>            Product: Networking
>            Version: 2.5
>      KernelVersion: 2.6.26.5
>           Platform: All
>         OS/Version: Linux
>               Tree: Mainline
>             Status: NEW
>           Severity: normal
>           Priority: P1
>          Component: IPV6
>         AssignedTo: yoshfuji@linux-ipv6.org
>         ReportedBy: adwol@zonk.pl
> 
> 
> Latest working kernel version: NONE
> Earliest failing kernel version: UNKNOWN
> Distribution: Various, mostly Slackware and PLD
> Hardware Environment: ANY
> Software Environment: ANY
> Problem Description: `echo 0 > /proc/sys/net/ipv6/conf/all/autoconf' doesn't
> disable interfaces autoconfiguration
> 
> Steps to reproduce:
> Changing values of /proc/sys/net/ipv6/conf/all/autoconf,
> /proc/sys/net/ipv6/conf/all/accept_ra and probably other
> /proc/sys/net/ipv6/conf/all/* controls don't cause anything.
> After `echo 0 > /proc/sys/net/ipv6/conf/all/autoconf' system still accepts
> router advertisement packets from gateway on every interface and set
> autoconfigured addresses.
> 
> Situation is rather deeper because autoconf is only an example and problem
> afflicts /proc/sys/net/ipv6/conf/all/* controls generally.
> 

Re: [Bugme-new] [Bug 11655] New: /proc/sys/net/ipv6/conf/all/* controls don't work

[David Miller]

From: Andrew Morton <akpm@linux-foundation.org>
Date: Thu, 2 Oct 2008 23:18:26 -0700

> (switched to email.  Please respond via emailed reply-to-all, not via the
> bugzilla web interface).

Not a bug.

These "global" setting have to be set to the desired value before the
device is created.  And it is at creation time that these global
values are "inherited" by the device.

Afterwards changes to the global value will not propagate to those
devices again, because that might override a changed setting made
by the user.

It is only newly created devices which get these values.

Re: [Bugme-new] [Bug 11655] New: /proc/sys/net/ipv6/conf/all/* controls don't work

[Adam Osuchowski]

David Miller wrote:
> Not a bug.
> 
> These "global" setting have to be set to the desired value before the
> device is created.  And it is at creation time that these global
> values are "inherited" by the device.
> 
> Afterwards changes to the global value will not propagate to those
> devices again, because that might override a changed setting made
> by the user.
> 
> It is only newly created devices which get these values.

I understand you are talking about /proc/sys/net/ipv6/conf/default/*
controls. If so, it's ok, but I talked about /proc/sys/net/ipv6/conf/all/*
controls. Documentation/networking/ip-sysctl.txt says:

    conf/default/*:
	    Change the interface-specific default settings.


    conf/all/*:
	    Change all the interface-specific settings.

so what is the difference between default and all in the context of your
statement? In my opinion, it could be understood that default settings
are inherited and those from "all" directory change values for all
current devices.

Re: [Bugme-new] [Bug 11655] New: /proc/sys/net/ipv6/conf/all/* controls don't work

[David Miller]

From: Adam Osuchowski <adwol@zonk.pl>
Date: Mon, 13 Oct 2008 12:13:34 +0200

> David Miller wrote:
> > Not a bug.
> > 
> > These "global" setting have to be set to the desired value before the
> > device is created.  And it is at creation time that these global
> > values are "inherited" by the device.
> > 
> > Afterwards changes to the global value will not propagate to those
> > devices again, because that might override a changed setting made
> > by the user.
> > 
> > It is only newly created devices which get these values.
> 
> I understand you are talking about /proc/sys/net/ipv6/conf/default/*
> controls. If so, it's ok, but I talked about /proc/sys/net/ipv6/conf/all/*
> controls. Documentation/networking/ip-sysctl.txt says:
> 
>     conf/default/*:
> 	    Change the interface-specific default settings.
> 
> 
>     conf/all/*:
> 	    Change all the interface-specific settings.
> 
> so what is the difference between default and all in the context of your
> statement? In my opinion, it could be understood that default settings
> are inherited and those from "all" directory change values for all
> current devices.

Unfortunately not all "all" knobs are treated universally, only some
of them all.

If you grep for "devconf_all" under net/ipv6 you'll see which ones
get used and in what manner.

Of course, we'll need to tweak either the docs or the implementation
to match :-)