From: Wanpeng Li <wanpen...@tencent.com>
If the target is self we do not need to yield, we can avoid malicious
guest to play this.
Signed-off-by: Wanpeng Li <wanpen...@tencent.com>
---
v1 -> v2:
* update comments
arch/x86/kvm/x86.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f08e9b4..ce9a1d2 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8231,6 +8231,10 @@ static void kvm_sched_yield(struct kvm_vcpu *vcpu,
unsigned long dest_id)
if (!target || !READ_ONCE(target->ready))
goto no_yield;
+ /* Ignore requests to yield to self */
+ if (vcpu == target)
+ goto no_yield;
+
if (kvm_vcpu_yield_to(target) <= 0)
goto no_yield;
--
2.7.4
