kvm: Cap halt polling at kvm->max_halt_poll_ns

When growing halt-polling, there is no check that the poll time exceeds the per-VM limit. It's possible for vcpu->halt_poll_ns to grow past kvm->max_halt_poll_ns and stay there until a halt which takes longer than kvm->halt_poll_ns. Signed-off-by: David Matlack <[email protected]> Signed-off-by: Venkatesh Srinivas <[email protected]> Message-Id: <[email protected]> Cc: [email protected] Signed-off-by: Paolo Bonzini <[email protected]>
kawasaki · May 7, 2021 · 258785e · 258785e
1 parent b269909
commit 258785e
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
@@ -2893,8 +2893,8 @@ static void grow_halt_poll_ns(struct kvm_vcpu *vcpu)
 	if (val < grow_start)
 		val = grow_start;
 
-	if (val > halt_poll_ns)
-		val = halt_poll_ns;
+	if (val > vcpu->kvm->max_halt_poll_ns)
+		val = vcpu->kvm->max_halt_poll_ns;
 
 	vcpu->halt_poll_ns = val;
 out: