#4322 NORM Never A: Kernel crash while suspending

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#4322: Kernel crash while suspending
---------------------+------------------------------------------------------
  Reporter:  wad     |       Owner:  dilinger      
      Type:  defect  |      Status:  new           
  Priority:  normal  |   Milestone:  Never Assigned
 Component:  kernel  |     Version:                
Resolution:          |    Keywords:                
  Verified:  0       |  
---------------------+------------------------------------------------------

Comment(by dilinger):

 {{{
 Oct 24 06:42:22 localhost kernel: [  228.831292] usb8xxx 1-1:1.0: suspend
 }}}
 Disable libertas driver on bus1

 {{{
 Oct 24 06:42:22 localhost kernel: [  228.831310] usb 1-1: suspend
 Oct 24 06:42:22 localhost kernel: [  230.077602] hub 2-0:1.0: suspend
 Oct 24 06:42:22 localhost kernel: [  230.077621] usb usb2: suspend, may
 wakeup
 }}}
 Disable bus2

 {{{
 Oct 24 06:42:22 localhost kernel: [  230.077655] hub 1-0:1.0: suspend
 Oct 24 06:42:22 localhost kernel: [  230.077671] usb usb1: suspend, may
 wakeup
 Oct 24 06:42:22 localhost kernel: [  230.077822] ehci_halt: 0 ->
 intr_enable
 Oct 24 06:42:22 localhost kernel: [  230.078068] ehci_bus_suspend:
 INTR_MASK ->
 intr_enable
 }}}
 Disable bus1, which uses the ehci driver.  Note that ehci_bus_suspend:
  - calls ehci_quiesce, which ensures the async schedule is deactivated
  - sets ehci->reclaim_ready = 1
  - calls ehci_work to clean up any leftover QHs
  - calls ehci_halt, which disables interrupts and waits for STS_HALT
  - reenables interrupts (?!)

 {{{
 Oct 24 06:42:22 localhost kernel: [  230.078087] ov7670 0-0042: suspend
 Oct 24 06:42:22 localhost kernel: [  230.078107] serial8250 serial8250:
 suspend
 Oct 24 06:42:22 localhost kernel: [  230.078208] platform vesafb.0:
 suspend
 Oct 24 06:42:22 localhost kernel: [  230.078227] platform pcspkr: suspend
 Oct 24 06:42:22 localhost kernel: [  230.078242] serial8250 serial8250.0:
 suspen
 d
 Oct 24 06:42:22 localhost kernel: [  230.078307] ehci_hcd 0000:00:0f.5:
 suspend
 Oct 24 06:42:22 localhost kernel: [  230.078322] usb_hcd_pci_suspend:
 enter
 Oct 24 06:42:22 localhost kernel: [  230.078337] ehci_pci_suspend: enter
 (event:
  2)
 Oct 24 06:42:22 localhost kernel: [  230.095153] ehci_pci_suspend: 0 ->
 intr_ena
 ble
 }}}
 Here's where we'd finally disable EHCI interrupts.  Problem is, in the
 original backtrace, we get an interrupt before we've had the chance to
 disable it.  I'm not sure yet whether the IRQ is spurious, or whether
 ehci_work (which can possibly set CMD_IAAD, drains the QH list, and
 doesn't wait for an IAA IRQ) is the cause.

-- 
Ticket URL: <https://dev.laptop.org/ticket/4322#comment:10>
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