This is a note to let you know that I've just added the patch titled
xhci: stop polling roothubs after shutdown
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
xhci-stop-polling-roothubs-after-shutdown.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From dc92944a014cd6a6f6c94299aaa36164dd2c238a Mon Sep 17 00:00:00 2001
From: Henry Lin <henryl@xxxxxxxxxx>
Date: Fri, 8 Apr 2022 16:48:22 +0300
Subject: xhci: stop polling roothubs after shutdown
From: Henry Lin <henryl@xxxxxxxxxx>
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@xxxxxxxxxxxxxxx
Signed-off-by: Henry Lin <henryl@xxxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220408134823.2527272-3-mathias.nyman@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/host/xhci.c | 11 +++++++++++
1 file changed, 11 insertions(+)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -746,6 +746,17 @@ void xhci_shutdown(struct usb_hcd *hcd)
if (xhci->quirks & XHCI_SPURIOUS_REBOOT)
usb_disable_xhci_ports(to_pci_dev(hcd->self.controller));
+ /* 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 */
Patches currently in stable-queue which might be from henryl@xxxxxxxxxx are
queue-4.9/xhci-stop-polling-roothubs-after-shutdown.patch
