From: Yaxiong Tian <tianyaxiong@xxxxxxxxxx>
when xHc restore state timeout,the xhci_reusme() return -ETIMEDOUT
instantly. After usb_hc_died() called ,they kick hub_wq to running
hub_event() but the wq is freezd. When suspend ends,hub_evnet realy
running and sticking.
Such as:
[ 968.794016][ 2] [ T37] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs"
disables this message.
[ 968.802969][ 2] [ T37] kworker/2:3 D 0 999 2 0x00000028
[ 968.809579][ 2] [ T37] Workqueue: usb_hub_wq hub_event
[ 968.814885][ 2] [ T37] Call trace:
[ 968.818455][ 2] [ T37] __switch_to+0xd4/0x138
[ 968.823067][ 2] [ T37] __schedule+0x2dc/0x6a0
[ 968.827680][ 2] [ T37] schedule+0x34/0xb0
[ 968.831947][ 2] [ T37] schedule_timeout+0x1e0/0x298
[ 968.837079][ 2] [ T37] __wait_for_common+0xf0/0x208
[ 968.842212][ 2] [ T37] wait_for_completion+0x1c/0x28
[ 968.847432][ 2] [ T37] xhci_configure_endpoint+0x104/0x640
[ 968.853173][ 2] [ T37] xhci_check_bandwidth+0x140/0x2e0
[ 968.858652][ 2] [ T37] usb_hcd_alloc_bandwidth+0x1c8/0x348
[ 968.864393][ 2] [ T37] usb_disable_device+0x198/0x260
[ 968.869698][ 2] [ T37] usb_disconnect+0xdc/0x3a0
[ 968.874571][ 2] [ T37] usb_disconnect+0xbc/0x3a0
[ 968.879441][ 2] [ T37] hub_quiesce+0xa0/0x108
[ 968.884053][ 2] [ T37] hub_event+0x4d4/0x1558
[ 968.888664][ 2] [ T37] kretprobe_trampoline+0x0/0xc4
[ 968.893884][ 2] [ T37] worker_thread+0x4c/0x488
[ 968.898668][ 2] [ T37] kthread+0xf8/0x128
[ 968.902933][ 2] [ T37] ret_from_fork+0x10/0x18
The result is that you cannot suspend again.because the wq can't
be freezed.Also hard to reboot,when some application visited this
piece.
The reason of stuck is that the xhci_resume() don't complete correctly.
In the error path before command |= CMD_RUN,the xhc should not be accessed.
To fix it, move set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags) and others
after "done:" .Also add HCD_HW_ACCESSIBLE() checks in
queue_command().
Suggested-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Signed-off-by: Yaxiong Tian <tianyaxiong@xxxxxxxxxx>
Signed-off-by: Hongyu Xie <xiehongyu1@xxxxxxxxxx>
---
drivers/usb/host/xhci-ring.c | 7 +++++--
drivers/usb/host/xhci.c | 10 +++++-----
2 files changed, 10 insertions(+), 7 deletions(-)
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 2c1d614b3b0f..ee6e06590974 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -4263,10 +4263,13 @@ static int queue_command(struct xhci_hcd *xhci, struct xhci_command *cmd,
{
int reserved_trbs = xhci->cmd_ring_reserved_trbs;
int ret;
+ struct usb_hcd *hcd = xhci_to_hcd(xhci);
if ((xhci->xhc_state & XHCI_STATE_DYING) ||
- (xhci->xhc_state & XHCI_STATE_HALTED)) {
- xhci_dbg(xhci, "xHCI dying or halted, can't queue_command\n");
+ (xhci->xhc_state & XHCI_STATE_HALTED) ||
+ !HCD_HW_ACCESSIBLE(hcd)) {
+ xhci_dbg(xhci,
+ "xHCI dying or halted,or hcd hw can't accessible,can't queue_command\n");
return -ESHUTDOWN;
}
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 08fbabff23a0..7f2c2b76a51c 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1006,10 +1006,6 @@ int xhci_resume(struct xhci_hcd *xhci, pm_message_t msg)
time_before(jiffies, xhci->usb3_rhub.bus_state.next_statechange))
msleep(100);
- set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
- if (xhci->shared_hcd)
- set_bit(HCD_FLAG_HW_ACCESSIBLE, &xhci->shared_hcd->flags);
-
spin_lock_irq(&xhci->lock);
if (hibernated || xhci->quirks & XHCI_RESET_ON_RESUME || xhci->broken_suspend)
@@ -1133,9 +1129,13 @@ int xhci_resume(struct xhci_hcd *xhci, pm_message_t msg)
spin_unlock_irq(&xhci->lock);
+ done:
+ set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+ if (xhci->shared_hcd)
+ set_bit(HCD_FLAG_HW_ACCESSIBLE, &xhci->shared_hcd->flags);
+
xhci_dbc_resume(xhci);
- done:
if (retval == 0) {
/*
* Resume roothubs only if there are pending events.
--
2.25.1
