KVM: arm64: Wrap the host with a stage 2

When KVM runs in protected nVHE mode, make use of a stage 2 page-table
to give the hypervisor some control over the host memory accesses. The
host stage 2 is created lazily using large block mappings if possible,
and will default to page mappings in absence of a better solution.

>From this point on, memory accesses from the host to protected memory
regions (e.g. not 'owned' by the host) are fatal and lead to hyp_panic().

Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210319100146.1149909-36-qperret@google.com
This commit is contained in:
Quentin Perret 2021-03-19 10:01:43 +00:00 • committed by Marc Zyngier
commit 1025c8c0c6
11 changed files with 316 additions and 7 deletions