On Thu, Feb 08, 2018 at 02:16:08PM +0000, Tomasz Janowski, Ph.D. wrote: > Dear USB developers, > > Based on my google research, the problem I experience seems to happen > with some newer smartphones. My test case is Samsung Galaxy S8 (SM-950U1). I am > trying to use USB tethering and everything seems to work as expected (modules > are loaded, Ethernet devices are up and running, dhcp works fine). I can connect to > the external world using both LTE or wireless network on the phone. > > Now, the problem is that the download speeds are terrible, around 64 KB/s, > while uploads are fast, the order of 15 MB/s. These speeds do not depend > on the wireless service provider: the results are similar when I tether wi-fi. > The USB Ethernet interface on the Linux host reports a lot of receive errors (attached: > device_state.txt), while kernel reports bad rndis messages (attached: kernel.log.txt). > > Windows 10 works great with the same hardware (same PC and same phone), with > uploads and downloads in the order of 150 Mbit/s, which is probably as fast as my > wireless network can do. But some people reported issues with older Windows drivers too. > Is possible that some newer version of RNDIS protocol is around and Linux hasn't updated > its RNDIS module yet? Hey, I was _just_ talking to someone at Google about this same issue yesterday, you beat him sending this same type of report to the mailing list, nice job :) Yes, this is not good, and we should work to resolve this, but first, what kernel version are you using? I think some fixes for the rndis driver went in recently to 4.15, but it would be good to verify that this isn't already resolved. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
