panic: ptrace status unexpected: got 9, wanted stopped

goroutine 1571465 [running]:
gvisor.googlesource.com/gvisor/pkg/sentry/platform/ptrace.(*thread).wait(0xc00176ad20, 0x0, 0x4bdd)
	pkg/sentry/platform/ptrace/subprocess.go:323 +0x3fb
gvisor.googlesource.com/gvisor/pkg/sentry/platform/ptrace.(*subprocess).switchToApp(0xc0006625c0, 0xc000367200, 0xd12c20, 0xc0010f4360, 0xc000a5fe00)
	pkg/sentry/platform/ptrace/subprocess.go:510 +0x381
gvisor.googlesource.com/gvisor/pkg/sentry/platform/ptrace.(*context).Switch(0xc000367200, 0xd09240, 0xc0006625c0, 0xd12c20, 0xc0010f4360, 0x7f56ffffffff, 0x0, 0x0, 0x0, 0x0)
	pkg/sentry/platform/ptrace/ptrace.go:102 +0x74
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*runApp).execute(0x0, 0xc00195c000, 0xcfca00, 0x0)
	pkg/sentry/kernel/task_run.go:209 +0x348
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).run(0xc00195c000, 0x2ede)
	pkg/sentry/kernel/task_run.go:95 +0x163
created by gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).Start
	pkg/sentry/kernel/task_start.go:279 +0xfe