linux/arch/arm64/kvm/hyp/include
Quentin Perret 66c57edd3b KVM: arm64: Restrict EL2 stage-1 changes in protected mode
The host kernel is currently able to change EL2 stage-1 mappings without
restrictions thanks to the __pkvm_create_mappings() hypercall. But in a
world where the host is no longer part of the TCB, this clearly poses a
problem.

To fix this, introduce a new hypercall to allow the host to share a
physical memory page with the hypervisor, and remove the
__pkvm_create_mappings() variant. The new hypercall implements
ownership and permission checks before allowing the sharing operation,
and it annotates the shared page in the hypervisor stage-1 and host
stage-2 page-tables.

Signed-off-by: Quentin Perret <qperret@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210809152448.1810400-21-qperret@google.com
2021-08-11 11:39:52 +01:00
..
hyp KVM: arm64: Save/restore MTE registers 2021-06-22 14:08:05 +01:00
nvhe KVM: arm64: Restrict EL2 stage-1 changes in protected mode 2021-08-11 11:39:52 +01:00