diff options
| -rw-r--r-- | arch/x86/kvm/x86.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index dd7b8b465675..dc7eb5fddfd3 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3292,9 +3292,6 @@ static void record_steal_time(struct kvm_vcpu *vcpu) } st = (struct kvm_steal_time __user *)ghc->hva; - if (!user_access_begin(st, sizeof(*st))) - return; - /* * Doing a TLB flush here, on the guest's behalf, can avoid * expensive IPIs. @@ -3303,6 +3300,9 @@ static void record_steal_time(struct kvm_vcpu *vcpu) u8 st_preempted = 0; int err = -EFAULT; + if (!user_access_begin(st, sizeof(*st))) + return; + asm volatile("1: xchgb %0, %2\n" "xor %1, %1\n" "2:\n" @@ -3325,6 +3325,9 @@ static void record_steal_time(struct kvm_vcpu *vcpu) if (!user_access_begin(st, sizeof(*st))) goto dirty; } else { + if (!user_access_begin(st, sizeof(*st))) + return; + unsafe_put_user(0, &st->preempted, out); vcpu->arch.st.preempted = 0; } |