DATA RACE in refs.(*WeakRef).init

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
gvisor	DATA RACE in refs.(*WeakRef).init (2)				1	1621d	1614d	0/26	fixed on 2020/02/07 00:17
WARNING: DATA RACE
Write at 0x00c42025e6e0 by goroutine 312:
  gvisor.googlesource.com/gvisor/pkg/refs.(*WeakRef).init()
      pkg/refs/refcounter.go:157 +0x45
  gvisor.googlesource.com/gvisor/pkg/refs.NewWeakRef()
      pkg/refs/refcounter.go:90 +0x8a
  gvisor.googlesource.com/gvisor/pkg/sentry/fs.(*Dirent).hashChildParentSet()
      pkg/sentry/fs/dirent.go:301 +0x115
  gvisor.googlesource.com/gvisor/pkg/sentry/fs.(*Dirent).hashChild()
      pkg/sentry/fs/dirent.go:286 +0xda
  gvisor.googlesource.com/gvisor/pkg/sentry/fs.(*Dirent).walk()
      pkg/sentry/fs/dirent.go:592 +0x537
  gvisor.googlesource.com/gvisor/pkg/sentry/fs.(*Dirent).Walk()
      pkg/sentry/fs/dirent.go:617 +0xd5
  gvisor.googlesource.com/gvisor/pkg/sentry/fs.(*MountNamespace).FindLink()
      pkg/sentry/fs/mounts.go:401 +0x202
  gvisor.googlesource.com/gvisor/pkg/sentry/fs.(*MountNamespace).FindInode()
      pkg/sentry/fs/mounts.go:439 +0x93
  gvisor.googlesource.com/gvisor/pkg/sentry/syscalls/linux.fileOpOn()
      pkg/sentry/syscalls/linux/sys_file.go:96 +0x173
  gvisor.googlesource.com/gvisor/pkg/sentry/syscalls/linux.Umount2()
      pkg/sentry/syscalls/linux/sys_mount.go:137 +0x1fc
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).executeSyscall()
      pkg/sentry/kernel/task_syscall.go:162 +0x14e
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke()
      pkg/sentry/kernel/task_syscall.go:280 +0x7d
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter()
      pkg/sentry/kernel/task_syscall.go:241 +0xc3
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscall()
      pkg/sentry/kernel/task_syscall.go:216 +0x19e
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*runApp).execute()
      pkg/sentry/kernel/task_run.go:219 +0x1501
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).run()
      pkg/sentry/kernel/task_run.go:95 +0x264

Previous read at 0x00c42025e6e0 by goroutine 450:
  sync/atomic.LoadInt64()
      bazel-out/k8-fastbuild/bin/external/io_bazel_rules_go/linux_amd64_static_race_stripped/stdlib%/src/runtime/race_amd64.s:211 +0xb
  sync/atomic.(*Value).Load()
      GOROOT/src/sync/atomic/value.go:30 +0x46
  gvisor.googlesource.com/gvisor/pkg/refs.(*WeakRef).get()
      pkg/refs/refcounter.go:99 +0x42
  gvisor.googlesource.com/gvisor/pkg/refs.(*WeakRef).Drop()
      pkg/refs/refcounter.go:124 +0x3c
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel/epoll.(*EventPoll).RemoveEntry()
      pkg/sentry/kernel/epoll/epoll.go:458 +0x249
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel/epoll.(*pollEntry).WeakRefGone()
      pkg/sentry/kernel/epoll/epoll.go:94 +0x83
  gvisor.googlesource.com/gvisor/pkg/refs.(*AtomicRefCount).DecRefWithDestructor()
      pkg/refs/refcounter.go:289 +0x158
  gvisor.googlesource.com/gvisor/pkg/sentry/fs.(*File).DecRef()
      pkg/sentry/fs/file.go:119 +0x79
  gvisor.googlesource.com/gvisor/pkg/sentry/syscalls/linux.Read()
      pkg/sentry/syscalls/linux/sys_read.go:69 +0x39c
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).executeSyscall()
      pkg/sentry/kernel/task_syscall.go:162 +0x14e
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke()
      pkg/sentry/kernel/task_syscall.go:280 +0x7d
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter()
      pkg/sentry/kernel/task_syscall.go:241 +0xc3
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscall()
      pkg/sentry/kernel/task_syscall.go:216 +0x19e
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*runApp).execute()
      pkg/sentry/kernel/task_run.go:219 +0x1501
  gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).run()
      pkg/sentry/kernel/task_run.go:95 +0x264