At 11/15/2012 07:34 AM, Rafael J. Wysocki Wrote: > On Tuesday, November 13, 2012 10:04:53 AM Wen Congyang wrote: >> At 11/13/2012 05:00 AM, Toshi Kani Wrote: >>> On Thu, 2012-11-08 at 19:04 +0800, Wen Congyang wrote: >>>> The memory device can be removed by 2 ways: >>>> 1. send eject request by SCI >>>> 2. echo 1 >/sys/bus/pci/devices/PNP0C80:XX/eject >>>> >>>> This 2 events may happen at the same time, so we may touch >>>> acpi_memory_device.res_list at the same time. This patch >>>> introduce a lock to protect this list. >>> >>> Hi Wen, >>> >>> This race condition is not unique in memory hot-remove as the sysfs >>> eject interface is created for all objects with _EJ0. For CPU >>> hot-remove, I addressed this race condition by making the notify handler >>> to run the hot-remove operation on kacpi_hotplug_wq by calling >>> acpi_os_hotplug_execute(). This serializes the hot-remove operations >>> among the two events since the sysfs eject also runs on >>> kacpi_hotplug_wq. This way is much simpler and is easy to maintain, >>> although it does not allow both operations to run simultaneously (which >>> I do not think we need). Can it be used for memory hot-remove as well? >> >> Good idea. I will update it. > > Still waiting. :-) > > But if you want that in v3.8, please repost ASAP. I think I will send it today. It is in test now. Thanks Wen Congyang > > Thanks, > Rafael > > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>