1. 06 11月, 2012 1 次提交
  2. 03 11月, 2012 2 次提交
    • H
      PCI/PM: Resume device before shutdown · 3ff2de9b
      Huang Ying 提交于
      Some actions during shutdown need device to be in D0 state, such as
      MSI shutdown etc, so resume device before shutdown.
      
      Without this patch, a device may not be enumerated after a kexec
      because the corresponding bridge is not in D0, so that
      configuration space of the device is not accessible.
      Signed-off-by: NHuang Ying <ying.huang@intel.com>
      Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
      CC: stable@vger.kernel.org		# v3.6+
      3ff2de9b
    • H
      PCI/PM: Fix deadlock when unbinding device if parent in D3cold · 90b5c1d7
      Huang Ying 提交于
      If a PCI device and its parents are put into D3cold, unbinding the
      device will trigger deadlock as follow:
      
      - driver_unbind
        - device_release_driver
          - device_lock(dev)				<--- previous lock here
          - __device_release_driver
            - pm_runtime_get_sync
              ...
                - rpm_resume(dev)
                  - rpm_resume(dev->parent)
                    ...
                      - pci_pm_runtime_resume
                        ...
                        - pci_set_power_state
                          - __pci_start_power_transition
                            - pci_wakeup_bus(dev->parent->subordinate)
                              - pci_walk_bus
                                - device_lock(dev)	<--- deadlock here
      
      
      If we do not do device_lock in pci_walk_bus, we can avoid deadlock.
      Device_lock in pci_walk_bus is introduced in commit:
      d71374da, corresponding email thread
      is: https://lkml.org/lkml/2006/5/26/38.  The patch author Zhang Yanmin
      said device_lock is added to pci_walk_bus because:
      
        Some error handling functions call pci_walk_bus. For example, PCIe
        aer. Here we lock the device, so the driver wouldn't detach from the
        device, as the cb might call driver's callback function.
      
      So I fixed the deadlock as follows:
      
      - remove device_lock from pci_walk_bus
      - add device_lock into callback if callback will call driver's callback
      
      I checked pci_walk_bus users one by one, and found only PCIe aer needs
      device lock.
      Signed-off-by: NHuang Ying <ying.huang@intel.com>
      Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
      CC: stable@vger.kernel.org		# v3.6+
      CC: Zhang Yanmin <yanmin.zhang@intel.com>
      90b5c1d7
  3. 26 10月, 2012 37 次提交