netdev - RE: changing usbnet's API to better deal with cdc-ncm

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <2AC7D4AD8BA1C640B4C60C61C8E520154A6AA574A0@EXDCVYMBSTM006.EQ1STM.local>
Date:	Fri, 7 Sep 2012 15:10:40 +0200
From:	Alexey ORISHKO <alexey.orishko@...ricsson.com>
To:	Ming Lei <tom.leiming@...il.com>
Cc:	Oliver Neukum <oneukum@...e.de>, "bjorn@...k.no" <bjorn@...k.no>,
	"netdev@...r.kernel.org" <netdev@...r.kernel.org>,
	"linux-usb@...r.kernel.org" <linux-usb@...r.kernel.org>,
	Alexey Orishko <alexey.orishko@...il.com>
Subject: RE: changing usbnet's API to better deal with cdc-ncm

> -----Original Message-----
> From: Ming Lei [mailto:tom.leiming@...il.com]
> Sent: Friday, September 07, 2012 2:58 PM

> > Several issues need to be improved:
> > Tx path:
> > 1. IP packets must be accumulated in one NTB. Currently it's done via
> data copy.
> > Preferred way would be a possibility to have a list of skb-s in
> resulting frame sent down.
> 
> Looks the copy is inevitable because the buffer length of each skb in
> the list is not possible to be max endpoint packet aligned, so one
> short packet may terminate the current tx urb transfer.

Zero or short packet shall not be added if resulting NTB is max negotiated size.
It's yet another problem with usbnet, where we had to add some workarounds
to avoid redundant short/zero packets.

Regards,
Alexey
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html