USB: serial: fix potential runtime pm imbalance at device remove
authorJohan Hovold <jhovold@gmail.com>
Mon, 26 May 2014 17:23:33 +0000 (19:23 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 27 May 2014 22:04:08 +0000 (15:04 -0700)
commitc14829fad88dbeda57253590695b85ba51270621
tree911ee5af3c0c0df403ae5346bf6e442a2c32406c
parentb0a9aa6da8088b722326a858ab572a13b5b6f9cb
USB: serial: fix potential runtime pm imbalance at device remove

Only call usb_autopm_put_interface() if the corresponding
usb_autopm_get_interface() was successful.

This prevents a potential runtime PM counter imbalance should
usb_autopm_get_interface() fail. Note that the USB PM usage counter is
reset when the interface is unbound, but that the runtime PM counter may
be left unbalanced.

Also add comment on why we don't need to worry about racing
resume/suspend on autopm_get failures.

Fixes: d5fd650cfc7f ("usb: serial: prevent suspend/resume from racing
against probe/remove")

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/serial/bus.c