Huang Ying 90b5c1d7c4 PCI/PM: Fix deadlock when unbinding device if parent in D3cold ... 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: d71374dafb, 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: Huang Ying <ying.huang@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> CC: stable@vger.kernel.org # v3.6+ CC: Zhang Yanmin <yanmin.zhang@intel.com>		2012-11-02 10:07:17 -06:00
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aer_inject.c	PCI: Introduce pci_pcie_type(dev) to replace pci_dev->pcie_type	2012-08-23 09:40:57 -06:00
aerdrv_acpi.c	PCI: Introduce pci_pcie_type(dev) to replace pci_dev->pcie_type	2012-08-23 09:40:57 -06:00
aerdrv_core.c	PCI/PM: Fix deadlock when unbinding device if parent in D3cold	2012-11-02 10:07:17 -06:00
aerdrv_errprint.c
aerdrv.c	Merge branch 'pci/stephen-const' into next	2012-09-12 13:54:10 -06:00
aerdrv.h
ecrc.c
Kconfig
Kconfig.debug
Makefile