From: Vitaly Kuznetsov <[email protected]>
HF2_GIF_MASK is set in env->hflags2 unconditionally on CPU reset
(see x86_cpu_reset()) but when calling KVM_SET_NESTED_STATE,
KVM_STATE_NESTED_GIF_SET is only valid for nSVM as e.g. nVMX code
looks like
if (kvm_state->hdr.vmx.vmxon_pa == -1ull) {
if (kvm_state->flags & ~KVM_STATE_NESTED_EVMCS)
return -EINVAL;
}
Also, when adjusting the environment after KVM_GET_NESTED_STATE we
need not reset HF2_GIF_MASK on VMX as e.g. x86_cpu_pending_interrupt()
expects it to be set.
Alternatively, we could've made env->hflags2 SVM-only.
Reported-by: Jan Kiszka <[email protected]>
Fixes: b16c0e20c742 ("KVM: add support for AMD nested live migration")
Signed-off-by: Vitaly Kuznetsov <[email protected]>
Message-Id: <[email protected]>
Tested-by: Jan Kiszka <[email protected]>
Signed-off-by: Eduardo Habkost <[email protected]>
---
target/i386/kvm.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)
diff --git a/target/i386/kvm.c b/target/i386/kvm.c
index b8455c89ed..6f18d940a5 100644
--- a/target/i386/kvm.c
+++ b/target/i386/kvm.c
@@ -3877,7 +3877,9 @@ static int kvm_put_nested_state(X86CPU *cpu)
} else {
env->nested_state->flags &= ~KVM_STATE_NESTED_GUEST_MODE;
}
- if (env->hflags2 & HF2_GIF_MASK) {
+
+ /* Don't set KVM_STATE_NESTED_GIF_SET on VMX as it is illegal */
+ if (cpu_has_svm(env) && (env->hflags2 & HF2_GIF_MASK)) {
env->nested_state->flags |= KVM_STATE_NESTED_GIF_SET;
} else {
env->nested_state->flags &= ~KVM_STATE_NESTED_GIF_SET;
@@ -3919,10 +3921,14 @@ static int kvm_get_nested_state(X86CPU *cpu)
} else {
env->hflags &= ~HF_GUEST_MASK;
}
- if (env->nested_state->flags & KVM_STATE_NESTED_GIF_SET) {
- env->hflags2 |= HF2_GIF_MASK;
- } else {
- env->hflags2 &= ~HF2_GIF_MASK;
+
+ /* Keep HF2_GIF_MASK set on !SVM as x86_cpu_pending_interrupt() needs it */
+ if (cpu_has_svm(env)) {
+ if (env->nested_state->flags & KVM_STATE_NESTED_GIF_SET) {
+ env->hflags2 |= HF2_GIF_MASK;
+ } else {
+ env->hflags2 &= ~HF2_GIF_MASK;
+ }
}
return ret;
--
2.26.2
