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Message-ID: <e361e3c0-069c-4e91-8f3a-d7ab2de8bdd4@quicinc.com>
Date:   Mon, 9 Oct 2023 23:57:44 +0530
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Subject: Re: [PATCH 2/2] usb: gadget: ncm: Add support to update
 wMaxSegmentSize via configfs
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC:     =?UTF-8?Q?Maciej_=C5=BBenczykowski?= <maze@google.com>,
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References: <20231009142005.21338-1-quic_kriskura@quicinc.com>
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 <2023100910-used-unruly-f750@gregkh>
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From:   Krishna Kurapati PSSNV <quic_kriskura@quicinc.com>
In-Reply-To: <2023100910-used-unruly-f750@gregkh>
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On 10/9/2023 11:24 PM, Greg Kroah-Hartman wrote:
> On Mon, Oct 09, 2023 at 09:02:32PM +0530, Krishna Kurapati PSSNV wrote:
>>
>>
>> On 10/9/2023 8:38 PM, Greg Kroah-Hartman wrote:
>>> On Mon, Oct 09, 2023 at 07:50:05PM +0530, Krishna Kurapati wrote:
>>>> Currently the NCM driver restricts wMaxSegmentSize that indicates
>>>> the datagram size coming from network layer to 1514.
>>>
>>> I don't see that restriction in the existing driver, where does that
>>> happen?
>>
>> Hi Greg,
>>
>>   In the ecm_desc, the following line restricts the value:
>>
>> .wMaxSegmentSize =      cpu_to_le16(ETH_FRAME_LEN),
> 
> Ok, so is that 1514?  I don't know as I don't know what ETH_FRAM_LEN is.
> 
Hi Greg,

Yes, that is 1514.

> So how about saying something to the affect of "the max segment size is
> currently limited to the ethernet frame length of the kernel which
> happens to be 1514 at this point in time."
> 

Sure. I will rephrase this in v2 with the suggestion provided.

Regards,
Krishna,