linux/drivers/base
Colin Cross 152e1d5920 PM: Prevent waiting forever on asynchronous resume after failing suspend
During suspend, the power.completion is expected to be set when a
device has not yet started suspending.  Set it on init to fix a
corner case where a device is resumed when its parent has never
suspended.

Consider three drivers, A, B, and C.  The parent of A is C, and C
has async_suspend set.  On boot, C->power.completion is initialized
to 0.

During the first suspend:
suspend_devices_and_enter(...)
 dpm_resume(...)
  device_suspend(A)
  device_suspend(B) returns error, aborts suspend
 dpm_resume_end(...)
   dpm_resume(...)
    device_resume(A)
     dpm_wait(A->parent == C)
      wait_for_completion(C->power.completion)

The wait_for_completion will never complete, because
complete_all(C->power.completion) will only be called from
device_suspend(C) or device_resume(C), neither of which is called
if suspend is aborted before C.

After a successful suspend->resume cycle, where B doesn't abort
suspend, C->power.completion is left in the completed state by the
call to device_resume(C), and the same call path will work if B
aborts suspend.

Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-09-09 00:49:43 +02:00
..
power PM: Prevent waiting forever on asynchronous resume after failing suspend 2010-09-09 00:49:43 +02:00
attribute_container.c [SCSI] attirbute_container: Initialize sysfs attributes with sysfs_attr_init 2010-03-27 15:15:24 -04:00
base.h Driver Core: devtmpfs - kernel-maintained tmpfs-based /dev 2009-09-15 09:50:49 -07:00
bus.c driver core: fix memory leak on one error path in bus_register() 2010-08-05 13:53:35 -07:00
class.c kobj: Add basic infrastructure for dealing with namespaces. 2010-05-21 09:37:31 -07:00
core.c driver core: device_rename's new_name can be const 2010-08-05 13:53:35 -07:00
cpu.c drivers/base/cpu.c: fix the output from /sys/devices/system/cpu/offline 2010-05-21 09:37:28 -07:00
dd.c Driver core: Add BUS_NOTIFY_BIND_DRIVER 2010-08-05 13:53:35 -07:00
devres.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
devtmpfs.c devtmpfs: support !CONFIG_TMPFS 2010-05-21 09:37:30 -07:00
dma-coherent.c Driver core: internal struct dma_coherent_mem, change type of a member. 2010-08-05 13:53:33 -07:00
dma-mapping.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
driver.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
firmware_class.c firmware_class: fix typo in error path 2010-08-23 18:12:46 -07:00
firmware.c firmware: change firmware_kset to firmware_kobj 2008-01-24 20:40:23 -08:00
hypervisor.c kobject: convert /sys/hypervisor to use kobject_create 2008-01-24 20:40:15 -08:00
init.c Driver Core: devtmpfs - kernel-maintained tmpfs-based /dev 2009-09-15 09:50:49 -07:00
iommu.c iommu-api: Remove iommu_{un}map_range functions 2010-03-07 18:01:13 +01:00
isa.c dma-mapping: replace all DMA_24BIT_MASK macro with DMA_BIT_MASK(24) 2009-04-07 08:31:12 -07:00
Kconfig devtmpfs: support !CONFIG_TMPFS 2010-05-21 09:37:30 -07:00
Makefile Driver Core: devtmpfs - kernel-maintained tmpfs-based /dev 2009-09-15 09:50:49 -07:00
map.c
memory.c Revert "memory-hotplug: add 0x prefix to HEX block_size_bytes" 2010-04-09 10:05:33 -07:00
module.c driver core: module.c: Use kasprintf 2010-05-21 09:37:29 -07:00
node.c drivers/base/node.c: reduce stack usage of node_read_meminfo() 2010-08-09 20:45:02 -07:00
platform.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6 2010-08-06 11:36:30 -07:00
sys.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
topology.c topology: convert cpu notifier to return encapsulate errno value 2010-05-27 09:12:48 -07:00
transport_class.c SCSI: convert struct class_device to struct device 2008-04-19 19:10:33 -07:00