-
James Morse authored
Hibernation represents a system state save/restore through a system reboot; this implies that the logical cpus carrying out hibernation/thawing must be the same, so that the context saved in the snapshot image on hibernation is consistent with the state of the system on resume. If resume from hibernation is driven through kernel command line parameter, the cpu responsible for thawing the system will be whatever CPU firmware boots the system on upon cold-boot (ie logical cpu 0); this means that in order to keep system context consistent between the hibernate snapshot image and system state on kernel resume from hibernate, logical cpu 0 must be online on hibernation and must be the logical cpu that creates the snapshot image. This patch adds a PM notifier that enforces logical cpu 0 is online when the hibernation is started (and prevents hibernation if it is not), which is sufficient to guarantee it will be the one creating the snapshot image therefore providing the resume cpu a consistent snapshot of the system to resume to. Signed-off-by:
James Morse <james.morse@arm.com> Acked-by:
Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by:
Catalin Marinas <catalin.marinas@arm.com> Signed-off-by:
Will Deacon <will.deacon@arm.com>
1fe492ce