diff options
| author | Quentin Perret <qperret@google.com> | 2021-03-19 10:01:43 +0000 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2021-03-19 12:02:18 +0000 |
| commit | 1025c8c0c6accfcbdc8f52ca1940160f65cd87d6 (patch) | |
| tree | 847ceaf1da72de962a340ab78b963d8cb32e7eb0 /arch/arm64/kvm/arm.c | |
| parent | def1aaf9e0bc6987bb4b417aac37226e994a1a74 (diff) | |
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
Diffstat (limited to 'arch/arm64/kvm/arm.c')
| -rw-r--r-- | arch/arm64/kvm/arm.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index a6b5ba195ca9..d237c378e6fb 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1894,12 +1894,22 @@ out_err: return err; } +void _kvm_host_prot_finalize(void *discard) +{ + WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize)); +} + static int finalize_hyp_mode(void) { if (!is_protected_kvm_enabled()) return 0; + /* + * Flip the static key upfront as that may no longer be possible + * once the host stage 2 is installed. + */ static_branch_enable(&kvm_protected_mode_initialized); + on_each_cpu(_kvm_host_prot_finalize, NULL, 1); return 0; } |