xhci: stop polling roothubs after shutdown

commit dc92944a014cd6a6f6c94299aaa36164dd2c238a upstream.

While rebooting, XHCI controller and its bus device will be shut down
in order by .shutdown callback. Stopping roothubs polling in
xhci_shutdown() can prevent XHCI driver from accessing port status
after its bus device shutdown.

Take PCIe XHCI controller as example, if XHCI driver doesn't stop roothubs
polling, XHCI driver may access PCIe BAR register for port status after
parent PCIe root port driver is shutdown and cause PCIe bus error.

[check shared hcd exist before stopping its roothub polling -Mathias]

Cc: stable@vger.kernel.org
Signed-off-by: Henry Lin <henryl@nvidia.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220408134823.2527272-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 7d1ad8d654cbbe20c6ef96b8424f31af5718b4eb..2b78ed323343396504b6dd000af4f79420c2d921 100644 (file)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -778,6 +778,17 @@ void xhci_shutdown(struct usb_hcd *hcd)
        if (xhci->quirks & XHCI_SPURIOUS_REBOOT)
                usb_disable_xhci_ports(to_pci_dev(hcd->self.sysdev));
 
+       /* Don't poll the roothubs after shutdown. */
+       xhci_dbg(xhci, "%s: stopping usb%d port polling.\n",
+                       __func__, hcd->self.busnum);
+       clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
+       del_timer_sync(&hcd->rh_timer);
+
+       if (xhci->shared_hcd) {
+               clear_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags);
+               del_timer_sync(&xhci->shared_hcd->rh_timer);
+       }
+
        spin_lock_irq(&xhci->lock);
        xhci_halt(xhci);
        /* Workaround for spurious wakeups at shutdown with HSW */