Created attachment 654832 [details]
I'm not sure if I should report it here or directly to linux kernel community. But maybe it has to do with the gentoo configuration.
Harware: z97 chipset.
Please notice both Gentoo installations run on the same hardware machine.
1. Insert the usb pendrive into the slot.
2. Wait until it is detected (observation with the help of dmesg -w).
3. Take out the usb pendrive from the slot.
4. Repeat steps 1-3 x times. I have tried with multiple pendrives.
5. Usb pendrive cannot be detected any more. Amperage is 0 (measured with a logilink measuring device). Dmesg shows the following issue:
systemd-udevd: sfX: Worker  processing SEQNUM=3192 is taking a long time
systemd-udevd: sfX: Worker  processing SEQNUM=3192 killed
Putting it in and taking it out again doesn't help. At least a couple of slots stop working at once. Probably all from a particular controller.
I can reproduce it pretty quickly. It takes about 1-5 minutes to reproduce. I can't link the problem to a specific pendrive. I think any might cause it.
The problem described in Gentoo 1 cannot be reproduced. I have tried over half an hour and I wasn't able to hang usb. Dmesg kept showing me the connection and disconnection and the pendrive was powered all the time.
I also described the problem here https://forums.gentoo.org/viewtopic-t-1117598.html Besides, I was only testing with usb 3.0.
Thanks for help.