sentry: make epoll.pollEntry wait for the file operation in restore.

PiperOrigin-RevId: 207737935
Change-Id: I3a301ece1f1d30909715f36562474e3248b6a0d5

pkg/sentry/fs/file.go

@@ -91,7 +91,7 @@ type File struct {
 	mu amutex.AbortableMutex `state:"nosave"`
 
 	// FileOperations implements file system specific behavior for this File.
-	FileOperations FileOperations
+	FileOperations FileOperations `state:"wait"`
 
 	// offset is the File's offset. Updating offset is protected by mu but
 	// can be read atomically via File.Offset() outside of mu.

pkg/sentry/fs/host/inode.go

@@ -77,7 +77,7 @@ type inodeFileState struct {
 	descriptor *descriptor `state:"wait"`
 
 	// Event queue for blocking operations.
-	queue waiter.Queue `state:"nosave"`
+	queue waiter.Queue `state:"zerovalue"`
 
 	// sattr is used to restore the inodeOperations.
 	sattr fs.StableAttr `state:"wait"`

pkg/sentry/kernel/epoll/epoll.go

@@ -61,7 +61,7 @@ const (
 //
 // +stateify savable
 type FileIdentifier struct {
-	File *fs.File
+	File *fs.File `state:"wait"`
 	Fd   kdefs.FD
 }