From bd82873f23c9a6ad834348f8b83f3b6a5bca2c65 Mon Sep 17 00:00:00 2001
From: Mathias Nyman <mathias.nyman@linux.intel.com>
Date: Wed, 11 Dec 2019 16:20:07 +0200
Subject: [PATCH] xhci: make sure interrupts are restored to correct state
Git-commit: bd82873f23c9a6ad834348f8b83f3b6a5bca2c65
No-fix: d12f592f95c956813e513a9f443f1375f5c73b28
Patch-mainline: v5.5-rc2
References: bsc#1051510
[ backport note: this is a backport from stable 4.14.y,
commit d12f592f95c956813e513a9f443f1375f5c73b28 ]
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>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/usb/host/xhci-hub.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -845,7 +845,7 @@ static u32 xhci_get_port_status(struct u
struct xhci_bus_state *bus_state,
__le32 __iomem **port_array,
u16 wIndex, u32 raw_port_status,
- unsigned long flags)
+ unsigned long *flags)
__releases(&xhci->lock)
__acquires(&xhci->lock)
{
@@ -935,12 +935,12 @@ static u32 xhci_get_port_status(struct u
xhci_set_link_state(xhci, port_array, wIndex,
XDEV_U0);
- spin_unlock_irqrestore(&xhci->lock, flags);
+ spin_unlock_irqrestore(&xhci->lock, *flags);
time_left = wait_for_completion_timeout(
&bus_state->rexit_done[wIndex],
msecs_to_jiffies(
XHCI_MAX_REXIT_TIMEOUT_MS));
- spin_lock_irqsave(&xhci->lock, flags);
+ spin_lock_irqsave(&xhci->lock, *flags);
if (time_left) {
slot_id = xhci_find_slot_id_by_port(hcd,
@@ -1088,7 +1088,7 @@ int xhci_hub_control(struct usb_hcd *hcd
break;
}
status = xhci_get_port_status(hcd, bus_state, port_array,
- wIndex, temp, flags);
+ wIndex, temp, &flags);
if (status == 0xffffffff)
goto error;