panic: ptrace status unexpected: got 9, wanted stopped

goroutine 448 [running]:
gvisor.googlesource.com/gvisor/pkg/sentry/platform/ptrace.(*thread).wait(0xc4207364b0, 0x1f)
	pkg/sentry/platform/ptrace/subprocess.go:304 +0x1e6
gvisor.googlesource.com/gvisor/pkg/sentry/platform/ptrace.(*subprocess).switchToApp(0xc42043efc0, 0xc4203b6cc0, 0xc7fa60, 0xc420594b40, 0x404800)
	pkg/sentry/platform/ptrace/subprocess.go:462 +0x384
gvisor.googlesource.com/gvisor/pkg/sentry/platform/ptrace.(*context).Switch(0xc4203b6cc0, 0xc79dc0, 0xc42043efc0, 0xc7fa60, 0xc420594b40, 0x7f93ffffffff, 0x0, 0x0, 0x0, 0x0)
	pkg/sentry/platform/ptrace/ptrace.go:102 +0x71
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*runApp).execute(0x0, 0xc420a3e000, 0xc6d860, 0x0)
	pkg/sentry/kernel/task_run.go:207 +0x17d
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).run(0xc420a3e000, 0x5e)
	pkg/sentry/kernel/task_run.go:95 +0x174
created by gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).Start
	pkg/sentry/kernel/task_start.go:251 +0x100