USB: core: document purpose of interface parent reference

USB interfaces hold a reference to their parent USB device to make sure
they do not outlive the parent.

Add a comment explaining that this reference is specifically needed for
asynchronous device resets and the device type need_parent_lock feature
(to allow driver core to lock the parent when only holding a reference
to the interface).

See commits:

  524134d42231 ("USB: don't cancel queued resets when unbinding drivers")
  0f554506a3fc ("driver core: fix parent lock use-after-free on USB disconnect")

for further details.

Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Link: https://patch.msgid.link/20261015074831.1418677-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

0 files changed, 0 insertions, 0 deletions