On 02/06/2025 23:44, Sean Christopherson wrote:
When creating an SEV-ES vCPU for intra-host migration, set its vmsa_pa to
INVALID_PAGE to harden against doing VMRUN with a bogus VMSA (KVM checks
for a valid VMSA page in pre_sev_run()).
Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Reviewed-by: Liam Merwick <liam.merwick@xxxxxxxxxx>
Tested-by: Liam Merwick <liam.merwick@xxxxxxxxxx>
---
arch/x86/kvm/svm/sev.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 93d899454535..5ebb265f2075 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -4471,8 +4471,12 @@ static void sev_es_init_vmcb(struct vcpu_svm *svm)
* the VMSA will be NULL if this vCPU is the destination for intrahost
* migration, and will be copied later.
*/
- if (svm->sev_es.vmsa && !svm->sev_es.snp_has_guest_vmsa)
- svm->vmcb->control.vmsa_pa = __pa(svm->sev_es.vmsa);
+ if (!svm->sev_es.snp_has_guest_vmsa) {
+ if (svm->sev_es.vmsa)
+ svm->vmcb->control.vmsa_pa = __pa(svm->sev_es.vmsa);
+ else
+ svm->vmcb->control.vmsa_pa = INVALID_PAGE;
+ }
/* Can't intercept CR register access, HV can't modify CR registers */
svm_clr_intercept(svm, INTERCEPT_CR0_READ);
