diff --git a/pkg/sentry/kernel/fasync/fasync.go b/pkg/sentry/kernel/fasync/fasync.go
index ff2095eda..0e6f4dc38 100644
--- a/pkg/sentry/kernel/fasync/fasync.go
+++ b/pkg/sentry/kernel/fasync/fasync.go
@@ -85,12 +85,17 @@ type FileAsync struct {
 	recipientT  *kernel.Task
 }
 
-func (a *FileAsync) recipient() *kernel.Task {
+// NotifyEvent implements waiter.EventListener.NotifyEvent.
+func (a *FileAsync) NotifyEvent(mask waiter.EventMask) {
 	a.mu.Lock()
-	defer a.mu.Unlock()
+	locked := true
+	defer func() {
+		if locked {
+			a.mu.Unlock()
+		}
+	}()
 	if !a.registered {
-		// No recipient has been registered.
-		return nil
+		return
 	}
 	t := a.recipientT
 	tg := a.recipientTG
@@ -100,34 +105,17 @@ func (a *FileAsync) recipient() *kernel.Task {
 	if tg != nil {
 		t = tg.Leader()
 	}
-	return t
-}
-
-// getPermAndSignal checks the credentials and returns the result of the
-// credentials check and signal.
-//
-//go:nosplit
-func (a *FileAsync) getPermAndSignal(c *auth.Credentials) (int32, bool) {
-	a.mu.Lock()
-	defer a.mu.Unlock()
-	sig := int32(a.signal)
+	if t == nil {
+		// No recipient has been registered.
+		return
+	}
+	c := t.Credentials()
 	// Logic from sigio_perm in fs/fcntl.c.
 	permCheck := (a.requester.EffectiveKUID == 0 ||
 		a.requester.EffectiveKUID == c.SavedKUID ||
 		a.requester.EffectiveKUID == c.RealKUID ||
 		a.requester.RealKUID == c.SavedKUID ||
 		a.requester.RealKUID == c.RealKUID)
-	return sig, permCheck
-}
-
-// NotifyEvent implements waiter.EventListener.NotifyEvent.
-func (a *FileAsync) NotifyEvent(mask waiter.EventMask) {
-	t := a.recipient()
-	if t == nil {
-		return
-	}
-	c := t.Credentials()
-	sig, permCheck := a.getPermAndSignal(c)
 	if !permCheck {
 		return
 	}
@@ -135,8 +123,8 @@ func (a *FileAsync) NotifyEvent(mask waiter.EventMask) {
 		Signo: int32(linux.SIGIO),
 		Code:  linux.SI_KERNEL,
 	}
-	if sig != 0 {
-		signalInfo.Signo = sig
+	if a.signal != 0 {
+		signalInfo.Signo = int32(a.signal)
 		signalInfo.SetFD(uint32(a.fd))
 		var band int64
 		for m, bandCode := range bandTable {
@@ -146,6 +134,8 @@ func (a *FileAsync) NotifyEvent(mask waiter.EventMask) {
 		}
 		signalInfo.SetBand(band)
 	}
+	a.mu.Unlock()
+	locked = false
 	t.SendSignal(signalInfo)
 }