On Thu, Feb 08, 2018 at 01:00:02PM -0800, The Real Bev wrote: > I think I have found a bug in the linux kernel 4.9.79. The problem > is in the performance of the driver for the Renesas Technology Corp. > uPD720201 > PCI-e USB host controller. > > My system has an Intel I7 960 cpu. The USB controller works when accessed > using the driver in the 4.8.10 kernel. Within the last few days > I compiled the 4.9.79 kernel using the same .config file as for > the 4.8.10 kernel except that I accepted the default for all kernel > options not already contained in the old config file. In other words, > starting with the .config file for the 4.8.10 kernel I did > make oldconfig > and defaulted on every question. > > Under the new kernel the system sees the host control via > lspci: > 09:00.0 USB controller: Renesas Technology Corp. uPD720201 USB 3.0 Host > Controller (rev 03) > > However nothing comes up in dmesg when I plug a device into the controller. Odds are you might have missed a build option for your system. Can you go back to your 4.8.y .config file and look at the new options to be sure that there was not one for the Renesas hardware you have? Also, 4.9 is really old, it's recommended you use something more modern, like 4.14 or even better yet, 4.15. 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
