"Rafael J. Wysocki" <rjw at sisk.pl> writes: > On Saturday, 22 of March 2008, Alan Stern wrote: > The spec doesn't say much about that, so we'll need to carry out some > experiments. > Still, as far as I can figure out what the spec authors _might_ mean, I think > that it would be inappropriate to restore the ACPI NVS area if S5 was entered > on "power off". The idea seems to be that the restoration of the ACPI NVS area > should complement whatever has been preserved by the platform over the > hibernation/resume cycle. > IMO, if S5 was entered on "powe off", there are two possible ways to go. > Either ACPI is initialized by the boot kernel, in which case the image kernel > should not touch things like _WAK and similar, just throw away whatever > ACPI-related state it got from the image and try to rebuild the ACPI-related > data from scratch. Or the boot kernel doesn't touch ACPI and the image kernel > initializes it in the same way as during a fresh boot (that might be difficult, > though). Just an added data partial point. In the kexec case I have had not heard anyone screaming to me that ACPI doesn't work after we switch kernels. So I expect shutting down ACPI and restarting it should work reliably and that is easy to test as that is already implemented with kexec. Eric
