When detaching device trees parent devices must be detached prior to
detaching its children. This is because parent devices can have
pointers to the child devices in their softcs which are not
invalidated by device_delete_child(). This can cause use after free
issues and panic().
Device drivers implementing trees, must ensure its detach function
detaches or deletes all its children before returning.
While at it remove now redundant device_detach() calls before
device_delete_child() and device_delete_children(), mostly in
the USB controller drivers.
Tested by: Jan Henrik Sylvester <me@janh.de>
Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D8070
MFC after: 2 weeks
(4 in operation), 4GB ram (3.5 usable) ARM machine.
Support covers device drivers for:
- Serial Peripheral Interface (SPI)
- Chrome Embedded Controller (EC) - SPI-based version
- XHCI and USB 3.0 dual-role device PHY
Also:
- Add support for Exynos5420 in Pad module
- Move power-related functions to separate driver --
Power Management Unit (PMU)
- Enable XHCI for Chromebook1
Special thanks to grehan@ for hardware, and to
hselasky@ for r269139.
