[PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Narendra_K]

Hello,

This patch allows users to specify if they want the onboard network
interfaces to be renamed to lomN by implementing a command line param
'udevlom'.

From: Narendra K <narendra_k@dell.com>
Subject: [PATCH] UDEV - Add 'udevlom' command line param to start_udev

This patch implements 'udevlom' command line parameter, which
when passed, results in onboard network interfaces getting
renamed to lomN.

Signed-off-by: Narendra K <narendra_k@dell.com>
---
 start_udev |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/start_udev b/start_udev
index 49fc286..57d60c9 100755
--- a/start_udev
+++ b/start_udev
@@ -32,6 +32,7 @@ export TZ=/etc/localtime
 . /etc/init.d/functions
 
 prog=udev
+cmdline=`cat /proc/cmdline`
 
 touch_recursive() {
 	( cd $1;
@@ -60,6 +61,10 @@ fi
 
 ret=$[$ret + $?]
 
+if strstr "$cmdline" udevlom; then
+	/sbin/udevadm control --env=UDEVLOM="y"
+fi
+
 /sbin/udevadm trigger --type=subsystems --action=add
 /sbin/udevadm trigger --type=devices --action=add
 /sbin/udevadm settle
-- 
1.7.3.1

With regards,
Narendra K

Re: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Greg KH]

On Wed, Nov 03, 2010 at 10:25:25PM +0530, Narendra_K@Dell.com wrote:
> Hello,
> 
> This patch allows users to specify if they want the onboard network
> interfaces to be renamed to lomN by implementing a command line param
> 'udevlom'.

Ick ick ick.

Why not do this in some other configuration file?  Don't rely on udev
being started with a different option, that is only ripe for abuse by
everyone else who wants their pet-project to get into the udev
environment.

Please, surely there's a different way to do this.

thanks,

greg k-h

Re: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Marco d'Itri]

[-- Attachment #1: Type: text/plain, Size: 505 bytes --]

On Nov 03, Greg KH <greg@kroah.com> wrote:

> Why not do this in some other configuration file?  Don't rely on udev
> being started with a different option, that is only ripe for abuse by
> everyone else who wants their pet-project to get into the udev
> environment.
Agreed. What about instructing users/installers to add something like
this in /etc/udev/rules.d/00-something.rules?

KERNEL=="eth*", ENV{UDEVLOM}="1"

(Maybe with a more descriptive name than "UDEVLOM".)

-- 
ciao,
Marco

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 198 bytes --]

Re: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Sujit K M]

> (Maybe with a more descriptive name than "UDEVLOM".)

What is different from the already used Name?

>
> --
> ciao,
> Marco
>
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v1.4.10 (GNU/Linux)
>
> iEYEARECAAYFAkzRqs8ACgkQFGfw2OHuP7EYEACZAeDc/phuXkT89y+bGtsYROYN
> Pw0An1Lti6pAyXjt/pjIj8L9h7V5hXTC
> =Keaz
> -----END PGP SIGNATURE-----
>
>



-- 
-- Sujit K M

blog(http://kmsujit.blogspot.com/)

Re: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Matt Domsch]

On Wed, Nov 03, 2010 at 11:05:00AM -0700, Greg KH wrote:
> On Wed, Nov 03, 2010 at 10:25:25PM +0530, Narendra_K@Dell.com wrote:
> > Hello,
> > 
> > This patch allows users to specify if they want the onboard network
> > interfaces to be renamed to lomN by implementing a command line param
> > 'udevlom'.
> 
> Ick ick ick.
> 
> Why not do this in some other configuration file?  Don't rely on udev
> being started with a different option, that is only ripe for abuse by
> everyone else who wants their pet-project to get into the udev
> environment.
> 
> Please, surely there's a different way to do this.

At Linux Plumbers Conference today, this problem space was discussed
once again, and I believe concensus on approach was reached.  Here
goes:

* If a 70-persistent-net.rules file sets a name, honor that.  This
  preserves existing installs.

* If BIOS provides indexes for onboard devices, honor that.
** Rename onboard NICs "lom[1-N]" as BIOS reports (# matches chassis labels)
** No rename for all others "ethX" (no change for NICs in PCI slots/USB/others)

* If neither are true, do not rename at all.

* Implementation will be:
** Udev rules to be included in upstream udev will read the index
   value from sysfs (provided by SMBIOS 2.6 info on kernels >= 2.6.36,
   PCI DSM info at some future point) if present, and rename LOMs
   based on that index value.  Distros will use these rules by default
   (Ubuntu and Fedora maintainers on board with the concept; I have
   not spoken with other distros yet.)
** Legacy distros with older udev rules will invoke biosdevname on
   kernels < 2.6.36 to get the same information, if present, and will
   rename LOMs based on index value.

** Installers will use the above udev rules by default.  If there is
   outcry during the distros beta testing periods, a way to disable
   these renames may be implemented.

* NetworkManager to display BIOS-provided labels as informational text


As such, biosdevname will be packaged and included in Debian and
Ubuntu (thanks to Colin Watson) to facilitate use in the udev rules.
Colin also suggested that any string used in Fedora kickstart files to
enable/disable this feature will also be used to enable/disable this
feature in the Debian & Ubuntu installers.  Given today's discussion
that the feature be enabled by default, this flag, if needed at all,
will be to disable the feature.

Does this seem sane to everyone?  Next step is to integrate
biosdevname into udev rules in a sane manner.

Thanks,
Matt

-- 
Matt Domsch
Technology Strategist, Dell Office of the CTO

Re: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Sujit K M]

> At Linux Plumbers Conference today, this problem space was discussed
> once again, and I believe concensus on approach was reached.  Here
> goes:

Was the patch a starting point for the discussion.

> * If a 70-persistent-net.rules file sets a name, honor that.  This
>  preserves existing installs.
>
> * If BIOS provides indexes for onboard devices, honor that.
> ** Rename onboard NICs "lom[1-N]" as BIOS reports (# matches chassis labels)
> ** No rename for all others "ethX" (no change for NICs in PCI slots/USB/others)
>
> * If neither are true, do not rename at all.

I would like to know what is the difference in the nomenclature for this.

>
> * Implementation will be:
> ** Udev rules to be included in upstream udev will read the index
>   value from sysfs (provided by SMBIOS 2.6 info on kernels >= 2.6.36,
>   PCI DSM info at some future point) if present, and rename LOMs
>   based on that index value.  Distros will use these rules by default
>   (Ubuntu and Fedora maintainers on board with the concept; I have
>   not spoken with other distros yet.)
> ** Legacy distros with older udev rules will invoke biosdevname on
>   kernels < 2.6.36 to get the same information, if present, and will
>   rename LOMs based on index value.

How will you manage these scenarios.
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Re: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Matt Domsch]

On Mon, Nov 08, 2010 at 02:12:56PM +0530, Sujit K M wrote:
> > At Linux Plumbers Conference today, this problem space was discussed
> > once again, and I believe concensus on approach was reached. ?Here
> > goes:
> 
> Was the patch a starting point for the discussion.

The discussion has been ongoing for 3 years.  This patch was posted
just prior to the conversation at LPC, where aspects of this patch
(reading values from sysfs and using them, if present) were discussed
at length.  The patch itself will have to undergo some changes based
on the outcome of that discussion.

 
> > * If a 70-persistent-net.rules file sets a name, honor that. ?This
> > ?preserves existing installs.
> >
> > * If BIOS provides indexes for onboard devices, honor that.
> > ** Rename onboard NICs "lom[1-N]" as BIOS reports (# matches chassis labels)
> > ** No rename for all others "ethX" (no change for NICs in PCI slots/USB/others)
> >
> > * If neither are true, do not rename at all.
> 
> I would like to know what is the difference in the nomenclature for this.

LOM == "LAN on Motherboard", aka "Embedded NIC".  I'm not wedded to
using "lomX", but it can't be ethX, and it must be short, and that's
as good as anything.

 
> > * Implementation will be:
> > ** Udev rules to be included in upstream udev will read the index
> > ? value from sysfs (provided by SMBIOS 2.6 info on kernels >= 2.6.36,
> > ? PCI DSM info at some future point) if present, and rename LOMs
> > ? based on that index value. ?Distros will use these rules by default
> > ? (Ubuntu and Fedora maintainers on board with the concept; I have
> > ? not spoken with other distros yet.)
> > ** Legacy distros with older udev rules will invoke biosdevname on
> > ? kernels < 2.6.36 to get the same information, if present, and will
> > ? rename LOMs based on index value.
> 
> How will you manage these scenarios.

I've had conversations with the relevant maintainers of the subsystems
of each of the major distributions.  What else are you looking for please?

Thanks,
Matt

-- 
Matt Domsch
Technology Strategist
Dell | Office of the CTO

Re: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Harald Hoyer]

On 11/03/2010 05:55 PM, Narendra_K@Dell.com wrote:
> Hello,
>
> This patch allows users to specify if they want the onboard network
> interfaces to be renamed to lomN by implementing a command line param
> 'udevlom'.
>
> From: Narendra K<narendra_k@dell.com>
> Subject: [PATCH] UDEV - Add 'udevlom' command line param to start_udev
>
> This patch implements 'udevlom' command line parameter, which
> when passed, results in onboard network interfaces getting
> renamed to lomN.
>
> Signed-off-by: Narendra K<narendra_k@dell.com>
> ---
>   start_udev |    5 +++++
>   1 files changed, 5 insertions(+), 0 deletions(-)
>
> diff --git a/start_udev b/start_udev
> index 49fc286..57d60c9 100755
> --- a/start_udev
> +++ b/start_udev
> @@ -32,6 +32,7 @@ export TZ=/etc/localtime
>   . /etc/init.d/functions
>
>   prog=udev
> +cmdline=`cat /proc/cmdline`
>
>   touch_recursive() {
>   	( cd $1;
> @@ -60,6 +61,10 @@ fi
>
>   ret=$[$ret + $?]
>
> +if strstr "$cmdline" udevlom; then
> +	/sbin/udevadm control --env=UDEVLOM="y"
> +fi
> +
>   /sbin/udevadm trigger --type=subsystems --action=add
>   /sbin/udevadm trigger --type=devices --action=add
>   /sbin/udevadm settle

start_udev is obsolete with the use of systemd service files anyway in Fedora>=15

Re: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Harald Hoyer]

On 11/10/2010 05:32 PM, Harald Hoyer wrote:
> On 11/03/2010 05:55 PM, Narendra_K@Dell.com wrote:
>> Hello,
>>
>> This patch allows users to specify if they want the onboard network
>> interfaces to be renamed to lomN by implementing a command line param
>> 'udevlom'.
>>
>> From: Narendra K<narendra_k@dell.com>
>> Subject: [PATCH] UDEV - Add 'udevlom' command line param to start_udev
>>
>> This patch implements 'udevlom' command line parameter, which
>> when passed, results in onboard network interfaces getting
>> renamed to lomN.
>>
>> Signed-off-by: Narendra K<narendra_k@dell.com>
>> ---
>> start_udev | 5 +++++
>> 1 files changed, 5 insertions(+), 0 deletions(-)
>>
>> diff --git a/start_udev b/start_udev
>> index 49fc286..57d60c9 100755
>> --- a/start_udev
>> +++ b/start_udev
>> @@ -32,6 +32,7 @@ export TZ=/etc/localtime
>> . /etc/init.d/functions
>>
>> prog=udev
>> +cmdline=`cat /proc/cmdline`
>>
>> touch_recursive() {
>> ( cd $1;
>> @@ -60,6 +61,10 @@ fi
>>
>> ret=$[$ret + $?]
>>
>> +if strstr "$cmdline" udevlom; then
>> + /sbin/udevadm control --env=UDEVLOM="y"
>> +fi
>> +
>> /sbin/udevadm trigger --type=subsystems --action=add
>> /sbin/udevadm trigger --type=devices --action=add
>> /sbin/udevadm settle
>
> start_udev is obsolete with the use of systemd service files anyway in Fedora>=15

not saying that we really should use "udevlom" on the kernel command line, but 
you could use:

IMPORT{cmdline}="udevlom"
KERNEL="eth*", ENV{udevlom}==1, ....

Re: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Matt Domsch]

On Thu, Nov 04, 2010 at 09:58:48PM -0500, Matt Domsch wrote:
> On Wed, Nov 03, 2010 at 11:05:00AM -0700, Greg KH wrote:
> > On Wed, Nov 03, 2010 at 10:25:25PM +0530, Narendra_K@Dell.com wrote:
> > > Hello,
> > > 
> > > This patch allows users to specify if they want the onboard network
> > > interfaces to be renamed to lomN by implementing a command line param
> > > 'udevlom'.
> > 
> > Ick ick ick.
> > 
> > Why not do this in some other configuration file?  Don't rely on udev
> > being started with a different option, that is only ripe for abuse by
> > everyone else who wants their pet-project to get into the udev
> > environment.
> > 
> > Please, surely there's a different way to do this.
> 
> At Linux Plumbers Conference today, this problem space was discussed
> once again, and I believe concensus on approach was reached.  Here
> goes:
> 
> * If a 70-persistent-net.rules file sets a name, honor that.  This
>   preserves existing installs.
> 
> * If BIOS provides indexes for onboard devices, honor that.
> ** Rename onboard NICs "lom[1-N]" as BIOS reports (# matches chassis labels)
> ** No rename for all others "ethX" (no change for NICs in PCI slots/USB/others)

I'm getting a lot of pushback from Dell customers on our
linux-poweredge mailing list (thread starts [1]) that the choice of
name "lomX" is poor, due to HP's extensive use of LOM meaning Lights
Out Management, rather than my intended meaning of "LAN on
Motherboard".  Gotta hate TLA collisions.

So, I'm open to new ideas for naming these.  At LPC, Ted noted that
2- and 3-letter names are expected.  "nic[1234]" or "en[1234]" ?

And yes, they'd prefer that we keep "eth[0123]" for the onboard
devices, but I simply don't see how to do that without kernel changes,
due to the races in both naming them in the kernel vs udev renaming,
and simple races between two udev processes.

Thanks,
Matt

[1] http://lists.us.dell.com/pipermail/linux-poweredge/2010-November/043576.html

-- 
Matt Domsch
Technology Strategist
Dell | Office of the CTO

Re: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Ben Hutchings]

On Mon, 2010-11-15 at 10:47 -0600, Matt Domsch wrote:
> On Thu, Nov 04, 2010 at 09:58:48PM -0500, Matt Domsch wrote:
> > On Wed, Nov 03, 2010 at 11:05:00AM -0700, Greg KH wrote:
> > > On Wed, Nov 03, 2010 at 10:25:25PM +0530, Narendra_K@Dell.com wrote:
> > > > Hello,
> > > > 
> > > > This patch allows users to specify if they want the onboard network
> > > > interfaces to be renamed to lomN by implementing a command line param
> > > > 'udevlom'.
> > > 
> > > Ick ick ick.
> > > 
> > > Why not do this in some other configuration file?  Don't rely on udev
> > > being started with a different option, that is only ripe for abuse by
> > > everyone else who wants their pet-project to get into the udev
> > > environment.
> > > 
> > > Please, surely there's a different way to do this.
> > 
> > At Linux Plumbers Conference today, this problem space was discussed
> > once again, and I believe concensus on approach was reached.  Here
> > goes:
> > 
> > * If a 70-persistent-net.rules file sets a name, honor that.  This
> >   preserves existing installs.
> > 
> > * If BIOS provides indexes for onboard devices, honor that.
> > ** Rename onboard NICs "lom[1-N]" as BIOS reports (# matches chassis labels)
> > ** No rename for all others "ethX" (no change for NICs in PCI slots/USB/others)
> 
> I'm getting a lot of pushback from Dell customers on our
> linux-poweredge mailing list (thread starts [1]) that the choice of
> name "lomX" is poor, due to HP's extensive use of LOM meaning Lights
> Out Management, rather than my intended meaning of "LAN on
> Motherboard".  Gotta hate TLA collisions.
> 
> So, I'm open to new ideas for naming these.  At LPC, Ted noted that
> 2- and 3-letter names are expected.  "nic[1234]" or "en[1234]" ?
[...]

I would suggest avoiding "nic" since some people use "NIC" to mean
specifically an add-in card rather than LOM.  In addition there is some
ambiguity with multi-port cards/controllers of whether NIC means a
controller or a port.

Other options for the prefix:
- "lan".  Maybe too generic.
- "mbe" = MotherBoard Ethernet. Looks a bit like "GbE" as some OEMs put
on the port labels.
- "eom" = Ethernet On Motherboard

Ben.

-- 
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.

Re: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Rick Jones]

>>I'm getting a lot of pushback from Dell customers on our
>>linux-poweredge mailing list (thread starts [1]) that the choice of
>>name "lomX" is poor, due to HP's extensive use of LOM meaning Lights
>>Out Management, rather than my intended meaning of "LAN on
>>Motherboard".  Gotta hate TLA collisions.

I think Sun (sorry, Oracle) push LOM for Lights-Out Management quite a lot - 
calling their service processor an iLOM IIRC.

>>So, I'm open to new ideas for naming these.  At LPC, Ted noted that
>>2- and 3-letter names are expected.  "nic[1234]" or "en[1234]" ?
> 
> [...]
> 
> I would suggest avoiding "nic" since some people use "NIC" to mean
> specifically an add-in card rather than LOM.  In addition there is some
> ambiguity with multi-port cards/controllers of whether NIC means a
> controller or a port.
> 
> Other options for the prefix:
> - "lan".  Maybe too generic.

yes and no - that is the prefix for "ethernet" network interface names in HP-UX, 
going back decades.  so, there is precedent for that, and given the way HP-UX 
device name persistence works, 99 times out of ten, the "built-in" or "core" LAN 
interfaces ended-up being enumerated starting from zero - lan0, lan1, etc. 
(There are exceptions relating to certain modles of systems and a full 
re-install of the OS with add-on cards present but that is a story for another 
thread).

> - "mbe" = MotherBoard Ethernet. Looks a bit like "GbE" as some OEMs put
> on the port labels.

Collides with Multi-Bit Error.

> - "eom" = Ethernet On Motherboard

Collides with End of Message.

If there is indeed *no* way to get then named eth[1-N], and "lan" doesn't 
resonate well-enough, then my contribution to the bikeshed would be "cor" simply 
because I don't know the TLA with which that collides :)

Are folks sufficently confident that using anything other than "eth" won't cause 
some unpleasant "our app always ass-u-me-d interfaces started with 'eth'" 
situations?

rick jones

RE: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Loke, Chetan]

> 
> > - "mbe" = MotherBoard Ethernet. Looks a bit like "GbE" as some OEMs
put
> > on the port labels.
> 
> Collides with Multi-Bit Error.
> 
> > - "eom" = Ethernet On Motherboard
> 
> Collides with End of Message.
> 

On board ethernet(obe)?
On board nic(obn)?

RE: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Loke, Chetan]

> 
> Are folks sufficently confident that using anything other than "eth"
> won't cause some unpleasant "our app always ass-u-me-d interfaces
started with
> 'eth'" situations?
> 

Good point. I'm sure folks use 'eth' in their regex filters. Please
ignore my obe/obn email.



> rick jones

Chetan Loke

Re: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Bill Fink]

On Wed, 24 Nov 2010, Loke, Chetan wrote:

> > Are folks sufficently confident that using anything other than "eth"
> > won't cause some unpleasant "our app always ass-u-me-d interfaces
> started with
> > 'eth'" situations?
> 
> Good point. I'm sure folks use 'eth' in their regex filters. Please
> ignore my obe/obn email.

If the 2 or 3 character name isn't a hard requirement, then
ethm for eth(ernet on )m(otherboard) would seem a natural
possibility.

					-Bill

Re: [PATCH 1/1] UDEV - Add 'udevlom' command line param to start_udev

[Matt Domsch]

On Wed, Nov 24, 2010 at 09:56:08PM -0500, Bill Fink wrote:
> On Wed, 24 Nov 2010, Loke, Chetan wrote:
> 
> > > Are folks sufficently confident that using anything other than "eth"
> > > won't cause some unpleasant "our app always ass-u-me-d interfaces
> > started with
> > > 'eth'" situations?
> > 
> > Good point. I'm sure folks use 'eth' in their regex filters. Please
> > ignore my obe/obn email.
> 
> If the 2 or 3 character name isn't a hard requirement, then
> ethm for eth(ernet on )m(otherboard) would seem a natural
> possibility.

I went with 'em' (embedded or ethernet-on-motherboard) in
biosdevname.  Git tree at:

http://linux.dell.com/cgi-bin/gitweb/gitweb.cgi?p=biosdevname.git;a=summary

Now I'm just trying to figure out why it seems pciutils libpci is
unhappy when the device tree is constantly changing underneath it,
such as when loading ixgbe max_vfs=63 - each new SR-IOV device created
launches a new udev instance as expected, but the device tree as seen
from any one of them may not be quite right as it's changing...

Thanks,
Matt

-- 
Matt Domsch
Technology Strategist
Dell | Office of the CTO