Re: [PATCH 1/1] TX throttling bug-fixing patch of AX88179_178A

Eric Dumazet
2013-07-25T05:11:02Z

On Thu, 2013-07-25 at 10:28 +0800, Ming Lei wrote:

>
> It depends if size of sg buffer(except for last one) in the sg list can be
> divided by usb endpoint's max packet size(512 or 1024), at least there
> is the constraint:
>
> http://git.kernel.org/cgit/linux/kernel/git/gregkh/usb.git/commit/?h=usb-next&id=10e232c597ac757e7f8600649f7e872e86de190f
>
> I am wondering if network stack can meet that. If not, it might be a
> bit difficult
> because lots of USB host controller don't support that, and driver may have
> to support SG and non-SG at the same time for working well on all HCs.

I do not see the problem.

If one skb has 2 fragments of 32KB, couldn't they be split into 64 1K
segments by the device driver ?