Commit 21369c77 authored Feb 10, 2014 by Rafael J. Wysocki

ACPI / hotplug / PCI: Execute _EJ0 under the ACPI scan lock



Since acpi_device_hotplug() assumes that ACPI handles of device
objects passed to it will not become invalid while acpi_scan_lock
is being held, make acpiphp_disable_slot() acquire acpi_scan_lock,
because it generally causes _EJ0 to be executed for one of the
devices in the slot and that may cause its ACPI handle to become
invalid.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

parent b169ba5a

drivers/pci/hotplug/acpiphp_glue.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -1007,9 +1007,15 @@ int acpiphp_disable_slot(struct acpiphp_slot *slot)
		{
		int ret;

		/*
		* Acquire acpi_scan_lock to ensure that the execution of _EJ0 in
		* acpiphp_disable_and_eject_slot() will be synchronized properly.
		*/
		acpi_scan_lock_acquire();
		pci_lock_rescan_remove();
		ret = acpiphp_disable_and_eject_slot(slot);
		pci_unlock_rescan_remove();
		acpi_scan_lock_release();
		return ret;
		}

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