• Rafael J. Wysocki's avatar
    Hibernation: Check if ACPI is enabled during restore in the right place · c7e0831d
    Rafael J. Wysocki authored
    The following scenario leads to total confusion of the platform firmware on
    some boxes (eg. HPC nx6325):
    * Hibernate with ACPI enabled
    * Resume passing "acpi=off" to the boot kernel
    
    To prevent this from happening it's necessary to check if ACPI is enabled (and
    enable it if that's not the case) _right_ _after_ control has been transfered
    from the boot kernel to the image kernel, before device_power_up() is called
    (ie.  with interrupts disabled).   Enabling ACPI after calling
    device_power_up() turns out to be insufficient.
    
    For this reason, introduce new hibernation callback ->leave() that will be
    executed before device_power_up() by the restored image kernel.   To make it
    work, it also is necessary to move swsusp_suspend() from swsusp.c to disk.c
    (it's name is changed to "create_image", which is more up to the point).
    Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
    Acked-by: default avatarPavel Machek <pavel@ucw.cz>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    c7e0831d
suspend.h 9.36 KB