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Wi-Fi Combo Forum Discussions

BeOl_4470266
Level 3
25 replies posted 10 replies posted 10 sign-ins
Level 3

Hello,

When could we expect support for the LwIP Chained Buffers?

At the moment, Wiced does not properly support LwIP without this. The Chained Buffers are a core feature of LwIP which cannot be deactivated.

My previous post was closed as Solved but the issue itself is not: https://community.infineon.com/t5/Wi-Fi-Combo/low-level-output-asserting-with-quot-No-chained-buffer...

Thanks for your support,

Best regards

 

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9 Replies
Rakesh_BG
Moderator
Moderator 10 likes received 25 solutions authored 50 replies posted
Moderator

Hi @BeOl_4470266 ,

Can you share the example code which you are using when you faced the problem mentioned in previous post.

Thanks & Regards,

Rakesh B G

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BeOl_4470266
Level 3
25 replies posted 10 replies posted 10 sign-ins
Level 3

Hi,

Thanks for your answer.

I don't have a practical subset of code to provide, but that should not be necessary anyway: the problem was clearly identified in the previous post on this subject.

When could we expect support for the LwIP Chained Buffers?

Thanks in advance for your support on this product,

Best regards

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AxLi_1746341
Level 7
10 comments on KBA 5 comments on KBA First comment on KBA
Level 7

This is nothing to do with application code.
lwIP supports chained pbuf and you can not stop it to do that.
(A packet may span over multiple pbufs, chained as a singly linked list. This is called a "pbuf chain".)

So the driver *must* take care of chained pbuf.

RoHe_4370821
Level 4
25 replies posted 25 sign-ins 10 replies posted
Level 4

Hi,


I too have a problem with this issue. The support for chained buffers is clearly missing and needs implemented. I see frequent TCP errors that I assume are as a result of this issue. I have attached a screenshot of the assertion that is hit in the debugger.

Regards,
Rob


image-2021-04-05-07-58-36-312.png

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Rakesh_BG
Moderator
Moderator 10 likes received 25 solutions authored 50 replies posted
Moderator

Hi @BeOl_4470266 ,

There is no plan to support lwIP buffer chaining in wiced. 

Regards,

Rakesh B G

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RoHe_4370821
Level 4
25 replies posted 25 sign-ins 10 replies posted
Level 4

Dear Infineon Support,

This issue needs to be fixed, as it is causing your customers products to have networking issues. A solution  needs to be implemented.

Regards,
Rob

AxLi_1746341
Level 7
10 comments on KBA 5 comments on KBA First comment on KBA
Level 7

@Rakesh_BG wrote:

Hi @BeOl_4470266 ,

There is no plan to support lwIP buffer chaining in wiced. 


@Rakesh_BG 

This is not requesting any new feature, but a bug fix.
Please clarify if the support team will fix this BUG or not.
I don't think people can wait endless here.

AxLi_1746341
Level 7
10 comments on KBA 5 comments on KBA First comment on KBA
Level 7

@Rakesh_BG 

I think 3 possible ways to address this bug.
1. Make WWD driver support chained pbuf
2. Hack lwIP to prevent chain pbuf
3. Convert chained pbuf into a single large pbuf before pass to WWD

You know people already hit this issue, the bug is real. This issue needs urgent fix.

AxLi_1746341
Level 7
10 comments on KBA 5 comments on KBA First comment on KBA
Level 7

@RaktimR_11 @Rakesh_BG @AditiB_81 

The "No chained buffers" assertion is also reported here: (Jun 05, 2019)
https://community.infineon.com/t5/Wi-Fi-Combo/iperf-with-LWIP-FreeRTOS/m-p/169566
Why there is no fix for more than 2 *years*.