Commit 7291edca authored Aug 02, 2019 by David Hildenbrand Committed by Linus Torvalds Aug 03, 2019

drivers/acpi/scan.c: document why we don't need the device_hotplug_lock

Let's document why the lock is not needed in acpi_scan_init(), right now
this is not really obvious.

[akpm@linux-foundation.org: fix tpyo]
Link: http://lkml.kernel.org/r/20190731135306.31524-1-david@redhat.com


Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 14c5ceba

drivers/acpi/scan.c

+6 −0

Original line number	Original line	Diff line number	Diff line
	@@ -2204,6 +2204,12 @@ int __init acpi_scan_init(void)
	acpi_gpe_apply_masked_gpes();		acpi_gpe_apply_masked_gpes();
	acpi_update_all_gpes();		acpi_update_all_gpes();

			/*
			* Although we call __add_memory() that is documented to require the
			* device_hotplug_lock, it is not necessary here because this is an
			* early code when userspace or any other code path cannot trigger
			* hotplug/hotunplug operations.
			*/
	mutex_lock(&acpi_scan_lock);		mutex_lock(&acpi_scan_lock);
	/*		/*
	* Enumerate devices in the ACPI namespace.		* Enumerate devices in the ACPI namespace.

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