I have an issue with mounting a cheap smart watch in #linux: Device is seen by the kernel, but never registered as a storage device /dev/sd*:

[dr_laemmerbein@mastodon.social]

@root42 Does it work with Windows or macOS without needing special drivers?

[root42@chaos.social]

@dr_laemmerbein Yes, it works fine in macOS as mass storage. No issue. However I just noticed that no other USB mass storage gets detected either. This is on the 2017 13" MacBook Pro. I have tried a USB thumb drive (That I installed Mint off of!) and a card reader with an SD card. No dice. Something is seriously wrong.

[sebastiaanfranken@mastodon.nl]

@root42 A USB storage device isn't mapped to /dev/sd*, since those are SATA devices. A USB flash drive reports itself as a SATA disk type so it gets mounted there, but this is probably under `/dev/mmcblk`

[root42@chaos.social]

Ok, the plot thickens. When booting from the Linux Mint USB stick, the USB ports work. But when booting the installed version, USB ports are broken. Why??

[zeri@chaos.social]

@root42 lack of USB modules for the kernel that boots?

[mbpaz@mas.to]

@root42 some udev rule in the installed version?

[root42@chaos.social]

@zeri could be! Which modules are required? Which package do they come in?

[root42@chaos.social]

@mbpaz maybe…? Would that influence lsusb not showing the attached devices?

[zeri@chaos.social]

@root42 don't know. But that's something it is probably safe to ask a chatbot ... worst case you load a module you don't need. Might also be that there are no modules because a kernel update failed.

[drscriptt@oldbytes.space]

@root42 @zeri compare the output of `lsmod` from both kernels.

Capture `dmesg` too.

One or both (sets) should get you on the correct path.

[root42@chaos.social]

@drscriptt @zeri yes, that’s my plan. Hope to find it’s just a module that’s missing.

[cheesefox@infosec.exchange]

@root42 @mbpaz potentially if usb_modeswitch is involved

[root42@chaos.social]

@cheesefox I have to look that up. My active desktop Linux times have been 15 years ago. Quite a bit has changed since then.

[root42@chaos.social]

@drscriptt So the output of lsmod is very similar on both. I installed an extra Intel sound driver, but that shouldn't interfere with USB, I think.

[root42@chaos.social]

So my current working hypothesis is: Live Linux Mint uses kernel 6.14, my installation uses kernel 6.17. This is probably what causes the regression?
So I might want to downgrade the kernel...
#linux #linuxmint

[root42@chaos.social]

Nope, that was not it. I downgraded to Linux 6.14.0-37, but USB still doesn't work. So it must be something with my installation! But what?

[cibersheep@mastodont.cat]

@root42 I still have some problemas mounting usb from friends in Ubuntu Focal. Can you believe that?
May it be a permissions issue?

[root42@chaos.social]

I am onto something: Attaching an OLD Apple keyboard with a USB-C to A adapter WORKS. But all my USB3.x devices do NOT work!
So how do I tell the USB controller to also work with USB3 devices...? Which works on the live thumbdrive!

[1024bytes@masto.ai]

@root42 it sounds like it does not load some usb drivers. But for default usb never seen that happen.

[root42@chaos.social]

Yes, so it seems the controller is stuck in EHCI mode, instead of switching to xHCI for USB3 devices. Bummer... how to switch it back...?