diff mbox series

[RFC,v2,07/10] KVM: arm64: Do not allow changes to private memory slots

Message ID 20240801090117.3841080-8-tabba@google.com (mailing list archive)
State New, archived
Headers show
Series KVM: Restricted mapping of guest_memfd at the host and pKVM/arm64 support | expand

Commit Message

Fuad Tabba Aug. 1, 2024, 9:01 a.m. UTC 
Handling changes to private memory slots can be difficult, since
it would probably require some cooperation from the hypervisor
and/or the guest. Do not allow such changes for now.

Signed-off-by: Fuad Tabba <tabba@google.com>
---
 arch/arm64/kvm/mmu.c | 4 ++++
 1 file changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index e632e10ea395..b1fc636fb670 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1970,6 +1970,10 @@  int kvm_arch_prepare_memory_region(struct kvm *kvm,
 			change != KVM_MR_FLAGS_ONLY)
 		return 0;
 
+	if ((change == KVM_MR_MOVE || change == KVM_MR_FLAGS_ONLY) &&
+	    ((kvm_slot_can_be_private(old)) || (kvm_slot_can_be_private(new))))
+		return -EPERM;
+
 	/*
 	 * Prevent userspace from creating a memory region outside of the IPA
 	 * space addressable by the KVM guest IPA space.