On Monday, 31 of December 2007, Ingo Molnar wrote: > > * Rafael J. Wysocki <rjw@xxxxxxx> wrote: > > > > ok, just to make sure we are talking about the same thing. Do you > > > mean we can restore an image saved by v2.6.12 into v2.6.24? I.e. a > > > 2.6.24 kernel will be able to run a 2.6.12 kernel's hibernation > > > image, with all the kernel internal data from v2.6.12, etc? No way > > > can that work. > > > > Well, not exactly. The support for different boot and image kernels > > has only been merged recently, but we can use the current git to > > restore 2.6.24-rc6-mm1, for example. > > > > The trick is to pass a little additional information in the image > > header that can be used by the boot kernel to locate the entry point > > to the image kernel and the image kernel's page tables. > > ok - i thought you meant that there's a general capability to resume > across kernel versions. (which would be close to impossible without some > major surgery.) Well, there will be one. :-) For example, one should be able to use a 2.6.25+ boot kernel to load the image containing 2.6.24-rc6 and restore the memory state from it. > btw., in what way is this different from kexec? Not that much different indeed. The hibernation code is more focused on restoring the pre-hibernation state of the system rather than anything else, plus on ACPI systems we try to handle the platform in accordance with the specification (to some extent - you'd have to use a non-ACPI boot kernel to follow the specification literally, which is possible but not straightforward). Rafael _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
