[PATCH v2 31/43] arm64: rme: Prevent Device mappings for Realms

Steven Price
2024-04-12T08:44:31Z

Physical device assignment is not yet supported by the RMM, so it
doesn't make much sense to allow device mappings within the realm.
Prevent them when the guest is a realm.

Signed-off-by: Steven Price <steven.price@arm.com>
---
arch/arm64/kvm/mmu.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index d891fc3c1a10..48c957e21c83 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1101,6 +1101,10 @@ int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
if (is_protected_kvm_enabled())
return -EPERM;

+ /* We don't support mapping special pages into a Realm */
+ if (kvm_is_realm(kvm))
+ return -EINVAL;
+
size += offset_in_page(guest_ipa);
guest_ipa &= PAGE_MASK;

--
2.34.1