Hello!

Recently I installed a new Debian 9.5 (kernel 4.9.0-8-amd64) with XFCE desktop on a Samsung 970 Evo M2-SSD

Now, after unmounting an USB device (HDD or pendrive) my system is freezing spontaneously. No input devices are responding. The only possible way to continue is a hard reset.
Logs only show series of null bytes (syslog, messages):
-- The crashes only occur with my file manager (Thunar 1.6.11), not from console.
-- Thunar works fine unmounting SATA devices.
-- No problems ever occured with my old (quite similar) Debian 9.5 system, installed on a SATA SSD (Samsung 860 Pro).

My hardware (unchanged except SSD):
ASRock Z170 Extreme4 (latest firmware)
Intel i5 6600T (using integrated graphics)
8 GB RAM

I would be grateful if someone could help!
Best wishes
Ernst

Hello again!

As it turned out, it's not unmounting the USB drive what's causing the trouble, but the following power-off command.
It makes no difference if it's done by thunar or from console.

1 members found this post helpful.

Thank you for this analysis! I don't know how you came to that conclusion, but this seems to be the exact issue that I have, too, though not on Thunar with Debian, but with Nautilus on Ubuntu 16.04 LTS, Kernel 4.4.0-139-generic. I don't know when it started exactly, a few days or maybe weeks ago. My workaround so far was just unmounting by hand from the console instead of using the GUI for it. Running udiskctl from console like that afterwards makes it freeze up the system completely like it does when using the GUI.

I registered on here just to thank you about this, and to subscribe to this thread to get to possibly get any updates. The closest and most recent similar thread that I could find before was https://forum.manjaro.org/t/hard-fre...sb-drive/29245

Hello!

I have discussed the problem in a German language Debian forum. Two days ago I've posted a Debian bugreport for the udidks2 package, but read (but could not verify) that this is a known and already fixed kernel bug (probably fixed in newer kernel versions only).

All file managers use this command if you "eject" the device. Thunar offers an "unmount" feature in the context menu to unmount without powering off the device, and I suppose, you will find such a feature in Nautilus as well.

For the moment it will do for me to avoid "eject" and use "unmount" instead. But I will update this thread when I have further information.

I have done further testing, posted a Debian bug report for udisks2 and found out:
It's primary a kernel bug in kernel 4.9.0-8-amd64 (and probably other versions of older kernels)
The command, used by various file managers for "safely remove devices", causes a complete system freeze.

It is NOT hardware related. My new system, cloned on a Samsung 860 Evo, freezes as well. My old system, cloned on the same SSD, doesn't. I couldn't find out what makes the difference, but I tested with the exact same hardware.

According to a Debian maintainer, it's a kernel bug and it is fixed in newer kernels. It's also not present in the previous Debian stable kernel (4.9.0-7-amd64, tested).

Funny enough, this one was fixed long ago but now with kernel 5.6.8-300.fc32.x86_64 and XFCE 4.14.0 I get that again.