fast boot cause usb storage can not work after resume

[Jing Wang]

mount a usb disk and then hibernate, after resume the mounted disk can not work.
analysis:
when resume the usb bus will be reporbed and reset the device address and the device node, that will case that the usb device can not work. For example mount a storage disk the device node is /dev/sdb when resume back, at list the usb bus system will find that the sdb has been allocated, so it will assign a new device(/dev/sdc) node to the same sotrage disk. So the old mounted point can not work.

solution:
suggest to umount the disk and then hiberante

[rob rhoads (rob-rhoads)]

Ramesh / Martin: Please update the status of this bug.

[martin (martin-xu)]

It is not a bug but a known linux USB system limitation/gap. I open this bug only want to track the gap.

Now, I do not know whether we need or have resource to meet the gap.

I suggestion set the bug as medium.

[rob rhoads (rob-rhoads)]

Martin is correct, this is a known limitation with Linux. Accordingly, I've set the importance to medium.

What should be fixed for our next release: Fast boot should unmount USB storage before suspending to disk.

[alek du (alek-du)]

Fixed it by back porting USB Persist feature to 2.6.22