arm64: KVM: VHE: Early interrupt handling
With VHE enabled, it is possible to let the kernel handle an interrupt
without saving the full guest context, and without restoring the full
host context either. This reduces the latency of handling an interrupt.
When an interrupt fires we can:
- save the guest's general purpose registers, shared system registers
and timer state
- switch to a host context (setting vectors, deactivating traps and
stage-2 translation)
- restore the host's shared sysregs
At that stage, we're able to jump to the interrupt handler.
On return from the handler, we can finish the switch (save/restore
whatever is missing from the above).
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
4 files changed
