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**james147** · Feb 10, 2013, 08:39 AM

Safely remove is designed to unmount then power down the device to make it safer to unplug, it is a reasonable default. I do think it should have an unmount button as well. Best way to achieve this is to report a bug upstream to kde if there is not one already.

**oshunluvr** · Feb 10, 2013, 10:36 AM

I've found reports of this problem back into 2009. I think it maybe device specific so there's not been one big solution for it. I've even found a couple bug reports but at least one of them was "Won't Fix".

Another bit of found info was a conversation from 2010 where the KDE devs decided that having both "Eject" and "Safely Remove" was too confusing for the masses (must have been some Gnome devs come over to rain on our parade

).

I supposed the issue was the device not being detected as a fixed device with removable media rather than a simple USB thumb drive. I don't have a USB cdrom, but wouldn't that sort of device potentially have the same problem? I was hoping for a simple udev rule or something like that could fix it. Alternately, somehow forcing "Eject" back into the dialog for this device would work as well.

The really odd bit is that it happens the second time you access the device and eject it, not the first. This leads me to believe the solution might lie in the power settings in the /sys/bus/usb device area but so far I haven't found the magic bullet.

**oshunluvr** · Feb 10, 2013, 10:55 AM

CORRECTION: It appears I maligned KDE devs too quickly. The comment was made by Canonical devs, not KDE.

**oshunluvr** · Feb 10, 2013, 11:54 AM

Can I solve this if I somehow get my device listed as "non-removable?"

**oshunluvr** · Feb 10, 2013, 12:09 PM

I did discover in the /sys/block/ location that removable is set to true for this reader. Is there a way to set the device to not removable at boot time? I tried editing the "removable" file directly, but it returns "input/output error"

**Snowhog** · Feb 10, 2013, 12:20 PM

The problem is that pluggable devices aren't know to the OS until they are plugged in. Once detected/identified they are dynamically attached to the file system tree. Once unmounted, it's gone, as if it had never been part of the file system. How then, would you tell the OS to recognize/reattach that which it no longer knows about? mount -a won't work, as it has no permanent entry in fstab. When plugged in, an entry for the device is registered in mtab and also in /proc/partitions. When unmounted, the mtab entry is removed and it is no longer listed in /proc/partitions.

You would have to have a way to manually kick off the detection routine.

**oshunluvr** · Feb 10, 2013, 12:57 PM

Actually, it the reader is detected by the OS at boot time. It's listed in the devices as sdc, sdd, sde, and sdf. It's not a hot-pluggable device - it's an sd card reader plugged into the internal USB bus connector. The problem is the device does not properly identify itself as non-removable.

**james147** · Feb 10, 2013, 01:16 PM

Originally posted by Snowhog View Post

The problem is that pluggable devices aren't know to the OS until they are plugged in. Once detected/identified they are dynamically attached to the file system tree. Once unmounted, it's gone, as if it had never been part of the file system. How then, would you tell the OS to recognize/reattach that which it no longer knows about? mount -a won't work, as it has no permanent entry in fstab. When plugged in, an entry for the device is registered in mtab and also in /proc/partitions. When unmounted, the mtab entry is removed and it is no longer listed in /proc/partitions.

You would have to have a way to manually kick off the detection routine.

The problem is not with unmounting, you can manually unmount a device and still have it known to the kernel. The problem is the device is powered down, and so has to be reinserted to power it up again, there is no way for software to do this. Some devices like card readers should not be powered down as you can unplug the media and insert another card in... but doing so will not power up the device if it has been powered down and so the whole device needs to be unplugged and plugged back in again.

Here is an example:

Code:

$ [B]ls /dev/sdf*[/B] # The usb is not pluged inls: cannot access /dev/sdf*: No such file or directory
$ [B]ls /dev/sdf*[/B] # After the usb is plugged in
/dev/sdf  /dev/sdf1
$ [B]sudo udisks --mount /dev/sdf1[/B]
Mounted /org/freedesktop/UDisks/devices/sdf1 at /media/9E3D-62E9
$ [B]ls /dev/sdf*[/B]
/dev/sdf  /dev/sdf1
$[B] sudo udisks --unmount /dev/sdf1[/B]
$ [B]ls /dev/sdf*[/B] # the device is still present
/dev/sdf  /dev/sdf1
$ [B]ls /dev/sdf*[/B] # After mounting and unmounting the device in kde
/dev/sdf

Notice the sdf1 partition is no longer available, this is identical to what happens if you eject the device (aka safely power it down)

Code:

$[B] ls /dev/sdf*[/B] # After plugging in the device again
/dev/sdf  /dev/sdf1
$ [B]sudo eject /dev/sdf[/B]
$ [B]ls /dev/sdf*[/B]
/dev/sdf
$[B] sudo partprobe /dev/sdf[/B]
Error: Error opening /dev/sdf: No medium found

And there is no way to get the device to be rescanned as it is powered down.

There is a difference between a device being powered on and unmounted and a device being powered off.

**oshunluvr** · Feb 10, 2013, 01:30 PM

So the udev properties don't list it as being removable or not but the system does list it as being removable. I can't find if I can set it to ATTRS{removable}=="0" in a udev rule...

**james147** · Feb 10, 2013, 01:43 PM

oshunluvr, you could try creating a custom udev rule to set the parameter for the specific device. Cannot remember the steps off hand but there are allot of udev guides out there.

**oshunluvr** · Feb 16, 2013, 01:56 PM

Still no joy of the udev rule. Half the guides out there are out of date. My rules are not being read. I'm using

SUBSYSTEM=="usb", ATTR{idVendor}=="0bda", ATTR{idProduct}=="0151", ENV{ID_INSTANCE}=="0:3",

to identify the devices, but no changes are being set. I'm trying these:

ENV{ID_DRIVE_FLASH_MS}="1", ENV{ID_DRIVE_EJECTABLE}="1", NAME="ms"

but nothing is taken effect. I added the name change just to see if if would use it - it doesn't.

**james147** · Feb 16, 2013, 03:28 PM

oshunluvr, try rebooting, cannot remember how to reload the udev rules while running...

**oshunluvr** · Feb 16, 2013, 03:34 PM

I did, but for the record supposedly

sudo udevadm control --reload-rules
or
sudo udevadm trigger

**james147** · Feb 16, 2013, 10:11 PM

I suggest reading through this: https://wiki.archlinux.org/index.php/Udev
And also this: http://www.reactivated.net/writing_udev_rules.html

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USB card reader powered off after "Safely Remove..."

USB card reader powered off after "Safely Remove..."

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