xhci: make sure interrupts are restored to correct state
authorMathias Nyman <mathias.nyman@linux.intel.com>
Wed, 11 Dec 2019 14:20:07 +0000 (16:20 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 17 Dec 2019 19:07:05 +0000 (20:07 +0100)
commit89159f7e47f2f140c32b0957e19219b23b1f7e15
treec7842a94b7b8eb647d7d4ac3c2faa424114e8370
parente03582344d00d7be9d24fbfeef8e4e74dce7401c
xhci: make sure interrupts are restored to correct state

commit bd82873f23c9a6ad834348f8b83f3b6a5bca2c65 upstream.

spin_unlock_irqrestore() might be called with stale flags after
reading port status, possibly restoring interrupts to a incorrect
state.

If a usb2 port just finished resuming while the port status is read
the spin lock will be temporary released and re-acquired in a separate
function. The flags parameter is passed as value instead of a pointer,
not updating flags properly before the final spin_unlock_irqrestore()
is called.

Cc: <stable@vger.kernel.org> # v3.12+
Fixes: 8b3d45705e54 ("usb: Fix xHCI host issues on remote wakeup.")
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20191211142007.8847-7-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/xhci-hub.c