diff options
| author | Oliver Upton <oliver.upton@linux.dev> | 2025-03-05 15:08:24 -0800 |
|---|---|---|
| committer | Oliver Upton <oliver.upton@linux.dev> | 2025-03-05 16:56:57 -0800 |
| commit | 03e1b89d051fadf37c617c2fe84304c1e800da91 (patch) | |
| tree | dbba11de0bcbd01a13ed04684914dcd84a7f3a96 | |
| parent | 9d91227364330fd1735d6fc3f7226f854f9f7b8c (diff) | |
KVM: arm64: Copy MIDR_EL1 into hyp VM when it is writable
KVM recently added a capability that allows userspace to override the
'implementation ID' registers presented to the VM. MIDR_EL1 is a special
example, where the hypervisor can directly set the value when read from
EL1 using VPIDR_EL2.
Copy the VM-wide value for MIDR_EL1 into the hyp VM for non-protected
guests when the capability is enabled so VPIDR_EL2 gets set up
correctly.
Reported-by: Mark Brown <broonie@kernel.org>
Closes: https://lore.kernel.org/kvmarm/ac594b9c-4bbb-46c8-9391-e7a68ce4de5b@sirena.org.uk/
Fixes: 3adaee783061 ("KVM: arm64: Allow userspace to change the implementation ID registers")
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250305230825.484091-3-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/pkvm.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/arm64/kvm/hyp/nvhe/pkvm.c b/arch/arm64/kvm/hyp/nvhe/pkvm.c index 96348abeb5c2..64a4a4c95bc3 100644 --- a/arch/arm64/kvm/hyp/nvhe/pkvm.c +++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c @@ -329,6 +329,10 @@ static void pkvm_init_features_from_host(struct pkvm_hyp_vm *hyp_vm, const struc bitmap_copy(kvm->arch.vcpu_features, host_kvm->arch.vcpu_features, KVM_VCPU_MAX_FEATURES); + + if (test_bit(KVM_ARCH_FLAG_WRITABLE_IMP_ID_REGS, &host_arch_flags)) + hyp_vm->kvm.arch.midr_el1 = host_kvm->arch.midr_el1; + return; } |