On Tue, 6 Dec 2016, Steffen Dirkwinkel wrote: > Hi all, > > I've been trying to debug issues with my rootfs on usb 3 flash drives > and suspending to ram. > > Symptoms: > > If I suspend and wake while my laptop is plugged into a charger > everything works perfectly. It looks like my laptop keeps usb power on > if a charger is plugged in. > > Without a charger the laptop locks up after waking due to ext4-fs errors. > > I'm not sure wether this is an issue with usb-persist power management > or something else. > > There are other people running into similar issues: > https://forum.manjaro.org/t/wake-up-problem-usb-3-0-after-suspend/10709 > https://bugzilla.kernel.org/show_bug.cgi?id=30912# > > Things I have tried: > - increasing retry count in drivers/usb/core/hub.c check_port_resume_type How high did you make it? Did you go as high as 10000? > - http://askubuntu.com/questions/505779/suspending-with-root-on-usb The explanation on that askubuntu page doesn't make a lot of sense. USB devices are detected during resume before kernel threads get woken up. The error messages listed in the log suggest that the connection to the device simply did not get re-established during the resume. > Things I might try: > - debug log to another device (would usb to serial work?) Maybe, but it's unlikely. > - inject 5v usb power using a powered hub? > - anything you suggest You should enable dynamic debugging in usbcore: echo 'module usbcore =p' >/sys/kernel/debug/dynamic_debug/control You'll probably have to use a network console to collect the debugging messages. Another thing you could try is connecting that USB-3 flash drive to a normal PC running Linux (so not as the root fs), and see what happens when you suspend and resume the system. Alan Stern -- 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
