panic after removing usb flash disk

[Ian Smith]

On Thu, 16 Aug 2007, Oliver Fromme wrote:

 > Roman Bogorodskiy wrote:
 >  > Artem Kuchin wrote:
 >  > > [FreeBSD crashes when a mounted device disappears]
 >  > 
 >  > It's not a bug, it's a feature.
 > 
 > I certainly wouldn't call it a feature.  As others have
 > noted, it is a known shortcoming in FreeBSD, and fixing
 > it is non-trivial.
 > 
 > Always remember to umount devices before removing them.

And don't ever allow a laptop with mounted (uhci, at least) USB device
to suspend; daX won't be accessible when it resumes, and not unloading
then reloading usb in rc.{suspend,resume} fails too.  umount panics.

 > Using amd(8) with a short timeout can help somewhat.

Will try next time; it might help with the suspend/resume issue if
it's been auto-unmounted, especially for idle timeout suspension.

Thanks, Ian