WARNING: DATA RACE
Read at 0x00c0003e4f48 by goroutine 395:
  gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).Brk()
      pkg/sentry/mm/syscalls.go:711 +0x167
  gvisor.googlesource.com/gvisor/pkg/sentry/syscalls/linux.Brk()
      pkg/sentry/syscalls/linux/sys_mmap.go:32 +0x77
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).executeSyscall()
      pkg/sentry/kernel/task_syscall.go:165 +0x407
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke()
      pkg/sentry/kernel/task_syscall.go:283 +0xb4
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter()
      pkg/sentry/kernel/task_syscall.go:244 +0x109
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscall()
      pkg/sentry/kernel/task_syscall.go:219 +0x1b6
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*runApp).execute()
      pkg/sentry/kernel/task_run.go:220 +0x18b9
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).run()
      pkg/sentry/kernel/task_run.go:92 +0x2e5

Previous write at 0x00c0003e4f48 by goroutine 479:
  gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).Brk()
      pkg/sentry/mm/syscalls.go:753 +0x3e1
  gvisor.googlesource.com/gvisor/pkg/sentry/syscalls/linux.Brk()
      pkg/sentry/syscalls/linux/sys_mmap.go:32 +0x77
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).executeSyscall()
      pkg/sentry/kernel/task_syscall.go:165 +0x407
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke()
      pkg/sentry/kernel/task_syscall.go:283 +0xb4
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter()
      pkg/sentry/kernel/task_syscall.go:244 +0x109
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscall()
      pkg/sentry/kernel/task_syscall.go:219 +0x1b6
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*runApp).execute()
      pkg/sentry/kernel/task_run.go:220 +0x18b9
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).run()
      pkg/sentry/kernel/task_run.go:92 +0x2e5