GVFS blocks multiple cameras of same brand, even when model differs

[Damon Lynch <damonlynch gmail com>]

Hello,

At some point, it appears GVFS began to enforce a rule that says only
one device with the same serial number is allowed, giving the message
akin to the following:

gvfs-gphoto2-vo[1746]: device /dev/bus/usb/005/011 has an identical
ID_SERIAL value to an existing device. Multiple devices are not
supported.

This is a problem because for some (all?) Canon DSLRs, the kernel
assigns the value Canon_Inc._Canon_Digital_Camera to ID_SERIAL. It
seems to occur regardless of model. I have access to only two Canon
DSLRs myself (very different models), but that's what I'm seeing.

Effectively that means when GIO/GVFS is running, the 2nd camera is
rejected. To the desktop user it appears as if nothing happened when
they insert it. Any program that uses libgphoto2 cannot see it either.

The primary libgphoto2 developer let me know that this ID_SERIAL
assignment is happening at the kernel level, not the libgphoto2
driver.

I've also confirmed that in an older version of GVFS (Ubuntu 16.04)
accepted multiple cameras of the same brand.

I imagine this behavior could be a real problem for people who run
things like camera traps in which one device controls multiple
cameras.

Assuming this is understood as a regression by GVFS developers, what
is the most effective way for me to file a bug report so that the right people
see it? (Or does this email suffice?) Is it a kernel USB or GVFS bug?

Best,
Damon

-- 
http://www.damonlynch.net