panic: munmap(600000, 200000)) failed: function not implemented

goroutine 6369791 [running]:
gvisor.googlesource.com/gvisor/pkg/sentry/platform/ptrace.(*subprocess).Unmap(0xc0007d2f00, 0x600000, 0x200000)
	pkg/sentry/platform/ptrace/subprocess.go:608 +0x372
gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).unmapASLocked(0xc0026b4000, 0x600000, 0x800000)
	pkg/sentry/mm/address_space.go:215 +0x7a
gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).getPMAsInternalLocked(0xc0026b4000, 0xe0bb80, 0xc002ad6000, 0xc0026b4080, 0x1, 0x6fa000, 0x6fb000, 0x101, 0x0, 0xc001e5bd80, ...)
	pkg/sentry/mm/pma.go:357 +0x12da
gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).getPMAsLocked(0xc0026b4000, 0xe0bb80, 0xc002ad6000, 0xc0026b4080, 0x1, 0x6fa000, 0x6fb000, 0x101, 0xc0026b4080, 0x2, ...)
	pkg/sentry/mm/pma.go:119 +0xec
gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).HandleUserFault(0xc0026b4000, 0xe0bb80, 0xc002ad6000, 0x6fa110, 0x101, 0x7f3e5b7f5a60, 0xc00244fc00, 0x100)
	pkg/sentry/mm/syscalls.go:57 +0x1ae
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*runApp).execute(0x0, 0xc002ad6000, 0xdf31e0, 0x0)
	pkg/sentry/kernel/task_run.go:256 +0x7d6
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).run(0xc002ad6000, 0xfddc)
	pkg/sentry/kernel/task_run.go:92 +0x194
created by gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).Start
	pkg/sentry/kernel/task_start.go:286 +0xfe