From PCManFM-Qt or Thunar (probably true with any file manager offering mount/unmount functionality through devel/gvfs and sysutils/bsdisks), unmounting an exFAT-formatted volume causes gvfs-udisks2-volume-monitor to hang at high CPU usage. This problem was mentioned on the FreeBSD forums and affects at least another person: https://forums.freebsd.org/threads/how-to-disable-bsdisks-automounter.78612/
I confirm it too. Also tried exFat flash dirves with Thunar or PCManFM. Manually umount using command and then camcontrol eject worked fine.
This should be a "sysutils/bsdisks:" bug, not "devel/gvfs". Adding bsdisks developer to CC. I might also try to replicate/fix this soon.
(In reply to Damjan Jovanovic from comment #2) Thanks! (And my apologies: it was probably me who suggested the wrong prefix.)
I wasn't able to reproduce the problem with KDE Dolphin as well. I installed PCManFM-Qt, but it doesn't show anything under "Devices" area. Maybe I have to build something with custom options?
Created attachment 230634 [details] Screenshot: Dolphin and PCManFM-Qt whilst using KDE Plasma (In reply to Gleb Popov from comment #4) Possible food for thought: preferences for PCManFM-Qt alongside (to the right of) preferences for KDE Plasma. I assume that (with Plasma running) Plasma preferences take precedence; for a disk that is connected after the launch of PCManFM-Qt: * a mount of its volume is _not_ automated – that said, the trio of checkboxes, in preferences for PCManFM-Qt, is a somewhat ambiguous combination.
I wonder if this report is related: https://foss.heptapod.net/bsdutils/bsdisks/-/issues/13 It says nothing about exFAT, though. Maybe the problem is not tied to the filesystem type?
No, I have removeable flash drives in exFat foramt and hard disks in NTFS file system. But only NTFS hard disks could be un-mounted/ejected without the problem mentioned in the bug report.
I tried again today. On my machine running 13.1-STABLE, exFAT is now properly handled: mounting and unmounting from PCManFM-Qt or Thunar works as expected and gvfs-udisks2-volume-monitor isn't causing any trouble anymore. Nice! On another machine running 13.1-RELEASE, the problem is now different: the file manager can mount an exFAT-formatted disk but can't unmount it ("operation not permitted"). Still not really convenient, but less annoying then having to kill a process eating the CPU. The main problem is gone and the fully functional stack will land in RELEASE sooner or later, so I consider this solved. Thank you!