Hello! TL;DR: I'm having troubles with Dell WD15 dock connected to USB-C of Dell Precision 5520 laptop. I'm seeing very frequent kernel freezes, sometimes panics, particularly on logging into the desktop session. I first created a ticket on Ubuntu Launchpad, but I have been directed to here. https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1701499 I've tried sending email to the linux-usb list from my private address, pkolaczk@xxxxxxxxx, but somehow I didn't get any answer - maybe my email didn't get through or just some incompatibility between gmail and majordomo (or I don't know how to use it properly). If you received a similar email previously, I'm sorry for duplicate. Please at least confirm this email got to the list, because Gmail does not display it in the inbox... Thanks. As for the problems. Hardware: - Dell Precision 5520 Laptop - WD15 USB-C Dock - External Dell U3011 display connected to the dock - Ethernet cable connected to the dock - wireless Logitech USB mouse, connected to the laptop directly (nano-receiver) - Logitech K290 keyboard connected to USB port of the dock Software: - Linux 4.12.13 / Linux 4.13.2 taken from Ubuntu ppa/mainline - either version has this problem(s). - Bios version: 1.5.0 - WD15 firmware: updated yesterday Problems: - If booted with the dock connected, system almost always totally freezes right after logging into desktop session, always after displaying the desktop and activating the external display, but before establishing the ethernet connection. Freeze is total, can't move mouse pointer, can't switch to TTY with Ctrl-Alt-F1. - Hotplugging the dock after getting to the grahical login screen works fine, but attempt to log in ends with freeze just as in the previous point. - Sometimes the system doesn't freeze, but ethernet connection doesn't come up. - Sometimes ethernet connection disconnects and can't be reestablished without reboot. - System sometimes fails to resume in the following scenarios: -- suspend, disconnect dock, resume -- suspend, connect the dock, resume What works fine: - Suspend/resume without connecting/disconnecting the dock seems to be working almost always fine. - Hotplugging the dock after starting the desktop session works fine (and is the only reliable workaround for the issue). - System never freezes before showing LightDM login screen, and at this point, external display, keyboard and ethernet connection work fine. - Laptop alone with no dock connected is perfectly stable. I didn't spot anything suspicious repeating in the syslog. There have been some General Protection Faults logged sometimes, but not every freeze causes logging any error information. I can send you some recent syslogs, if you wish. Tell me what else I can do to help you debug the issue and fix it. I can build kernel from source and test patches if you wish. Thanks, Piotr Kołaczkowski -- 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
