Re: net/hsr: not working : High-availability Seamless Redundancy (HSRv0)

Re: net/hsr: not working : High-availability Seamless Redundancy (HSRv0)

[Arvid Brodin]

On 2014-06-10 14:42, Gokul C G wrote:
> Hi,
> 
> I am trying to incorporate the changes made for High-availability
> Seamless Redundancy (HSRv0) in linux 3.13  into one of the older
> version  Linux 3.0.48 . I had made changes as per patch in 3.0.48
> kernel and modified  use of  NETLINK_CB(skb_in).portid to
> NETLINK_CB(skb_in).pid and info->snd_portid to info->snd_pid since
> the variable are renamed recently for better readability , added new
> list related  macro(like list_for_each_entry_rcu) to old kernel .
> 
> I am doing this for a Big-endian system with powerpc architecture
> with real-time functionality enabled . The kernel occurred while
> probing hsr/prp driver and following  console information available.
> I had tried to compile HSRv0 driver with kernel and also as kernel
> module , in both cases following crash message found on console.
> 

This is of course impossible for anyone else but yourself to debug, 
since noone else has access to the exact code you are using.

If you are able to recreate the bug on a current, vanilla kernel, 
someone might be able to help.


-- 
Arvid Brodin | Consultant (Linux)
ALTEN | Knarrarnäsgatan 7 | SE-164 40 Kista | Sweden
arvid.brodin@alten.se | www.alten.se/en/

Re: net/hsr: not working : High-availability Seamless Redundancy (HSRv0)

[Arvid Brodin]

On 2014-06-16 12:08, Gokul C G wrote:
> Hi,
> 
> is snmp mapping of PRP/HSR service is available in current driver ?
> if not is there any plan to incorporate changes for SNMP mapping in HSR/PRP driver ?
> It would be better if we could implement PRP/HSR service-mapping to SNMP.

I have not done any work on SNMP for HSR, and I don't currently know of any plans to 
implement it.


-- 
Arvid Brodin | Consultant (Linux)
ALTEN | Knarrarnäsgatan 7 | SE-164 40 Kista | Sweden
arvid.brodin@alten.se | www.alten.se/en/

Re: net/hsr: not working : High-availability Seamless Redundancy (HSRv0)

[Arvid Brodin]

On 2014-06-16 14:33, Gokul C G wrote:
> Hi,
> 
> PRP is protected by a number of patents. Does we need to  obtain
> license for those to make use of the patented technology and offer a
> PRP driver to end customers , if we use linux in embedded platform
> ??

I am not a patent expert, nor a lawyer, so I cannot advise you in this matter.
My understanding as a layman is that if there is a valid patent that covers the
code, then yes, you need to obtain a license to be allowed to offer a product
making use of the technology to end customers.


> I could find something like following while googling about HSR/PRP , 
> "In order to be compliant with the Linux open source licensing model,
> the Linux implementation of the PRP driver is in user space, not
> kernel space."  I couldn't understand the same !!

From a patent perspective, I don't *think* it matters if the implementation is 
in kernel space or user space; you'd need a license either way. By implementing 
the driver in user space you don't have to make the source code available under 
GPL, though. Again, I am not a lawyer, so don't take my word for it.


> whether Kernel implementation of HSR is problematic from a legal
> point of view (patent violation, see above for PRP) ??

Possibly. The HSRv0 standard cautions about patents regarding PRP (the PRP 
duplicate discard algorithm, using a Redundancy Control Trailer) and interactions
between HSR and PRP nets. HSR does not use a Redundancy Control Trailer.

The HSRv1 standard also cautions about patent claims for interconnecting HSR nets
though QuadBoxes, and additional PRP patents. 

I have no idea if these claims are valid, and I don't know if these are the only 
parts of the standard which may be patent encumbered. 

From the standard: "ISO (www.iso.org/patents) and IEC (http://patents.iec.ch) 
maintain on-line data bases of patents relevant to their standards. Users are 
encouraged to consult the data bases for the most up to date information 
concerning patents."


-- 
Arvid Brodin | Consultant (Linux)
ALTEN | Knarrarnäsgatan 7 | SE-164 40 Kista | Sweden
arvid.brodin@alten.se | www.alten.se/en/