diff options
| author | Will Deacon <will@kernel.org> | 2022-11-10 22:02:55 +0300 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2022-11-11 20:19:35 +0300 |
| commit | 73f38ef2ae531b180685173e0923225551434fcb (patch) | |
| tree | c67b03ec07350daca0afc1f04806115d3f5da43f /arch/arm64/kvm/hyp/nvhe/pkvm.c | |
| parent | fe41a7f8c0ee3ee2f682f8c28c7e1c5ff2be8a79 (diff) | |
| download | linux-73f38ef2ae531b180685173e0923225551434fcb.tar.xz | |
KVM: arm64: Maintain a copy of 'kvm_arm_vmid_bits' at EL2
Sharing 'kvm_arm_vmid_bits' between EL1 and EL2 allows the host to
modify the variable arbitrarily, potentially leading to all sorts of
shenanians as this is used to configure the VTTBR register for the
guest stage-2.
In preparation for unmapping host sections entirely from EL2, maintain
a copy of 'kvm_arm_vmid_bits' in the pKVM hypervisor and initialise it
from the host value while it is still trusted.
Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-23-will@kernel.org
Diffstat (limited to 'arch/arm64/kvm/hyp/nvhe/pkvm.c')
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/pkvm.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/arm64/kvm/hyp/nvhe/pkvm.c b/arch/arm64/kvm/hyp/nvhe/pkvm.c index 81835c2f4c5a..ed6ceac1e854 100644 --- a/arch/arm64/kvm/hyp/nvhe/pkvm.c +++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c @@ -15,6 +15,9 @@ /* Used by icache_is_vpipt(). */ unsigned long __icache_flags; +/* Used by kvm_get_vttbr(). */ +unsigned int kvm_arm_vmid_bits; + /* * Set trap register values based on features in ID_AA64PFR0. */ |