On Wed 2007-08-22 10:19:03, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rjw@xxxxxxx> > > Make it possible to restore a hibernation image on x86_64 with the help of a > kernel different from the one in the image. > > The idea is to split the core restoration code into two separate parts and to > place each of them in a different page. The first part belongs to the boot > kernel and is executed as the last step of the image kernel's memory restoration > procedure. It restores all of the image kernel's memory that has not been > restored yet except for the one page containing the very code that is being > executed at that time. The final operation performed by it is a jump to the > second part of the core restoration code that belongs to the image kernel and > has just been restored. This code restores the last remaining page of the image > kernel's memory containing the first, already executed, part of the core > restoration code (temporary page tables created by the boot kernel are used at > this stage). It also makes the CPU switch to the image kernel's page tables and > restores the state of general purpose registers (including the stack pointer) > from before the hibernation. > > The main issue with this idea is that in order to jump to the second part of the > restoration code the boot kernel needs to know its address. However, this > address may be passed to it in the image header. Namely, the part of the image > header previously used for checking if the version of the image kernel is > correct can be replaced with some architecture specific data that will allow > the boot kernel to jump to the right address within the image kernel. These > data should also be used for checking if the image kernel is compatible with > the boot kernel (as far as the memory restroration procedure is concerned). > It can be done, for example, with the help of a "magic" value that has to be > equal in both kernels, so that they can be regarded as compatible. > > Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx> ACK. -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
