WARNING: DATA RACE
Read at 0x00c0003401c8 by goroutine 333:
  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
DIAGNOSIS:
I0501 09:01:05.491216   28088 x:0] ***************************
I0501 09:01:05.491349   28088 x:0] Args: [/syzkaller/managers/ptrace-proxy-sandbox-race/current/image -root /syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root -watchdog-action=panic -network=none -debug -platform=ptrace -file-access=shared -network=sandbox debug -stacks ci-gvisor-ptrace-proxy-sandbox-race-0]
I0501 09:01:05.491410   28088 x:0] Version release-20190304.1-163-g8bfb83d0acde
I0501 09:01:05.491431   28088 x:0] PID: 28088
I0501 09:01:05.491463   28088 x:0] UID: 0, GID: 0
I0501 09:01:05.491486   28088 x:0] Configuration:
I0501 09:01:05.491497   28088 x:0] 		RootDir: /syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root
I0501 09:01:05.491528   28088 x:0] 		Platform: ptrace
I0501 09:01:05.491574   28088 x:0] 		FileAccess: shared, overlay: false
I0501 09:01:05.491598   28088 x:0] 		Network: sandbox, logging: false
I0501 09:01:05.491624   28088 x:0] 		Strace: false, max size: 1024, syscalls: []
I0501 09:01:05.491646   28088 x:0] ***************************
D0501 09:01:05.491706   28088 x:0] Load container "/syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root" "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0501 09:01:05.497408   28088 x:0] Signal container "ci-gvisor-ptrace-proxy-sandbox-race-0": signal 0
D0501 09:01:05.497474   28088 x:0] Signal sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0501 09:01:05.497522   28088 x:0] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0501 09:01:05.497869   28088 x:0] urpc: successfully marshalled 117 bytes.
D0501 09:01:05.499055   28088 x:0] urpc: unmarshal success.
I0501 09:01:05.499191   28088 x:0] Found sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0", PID: 27355
I0501 09:01:05.499259   28088 x:0] Retrieving sandbox stacks
D0501 09:01:05.499289   28088 x:0] Stacks sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0501 09:01:05.499344   28088 x:0] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0501 09:01:05.499489   28088 x:0] urpc: successfully marshalled 36 bytes.
D0501 09:01:05.621690   28088 x:0] urpc: unmarshal success.
I0501 09:01:05.621849   28088 x:0]      *** Stack dump ***
goroutine 1241 [running]:
gvisor.googlesource.com/gvisor/pkg/log.Stacks(0x45c801, 0xc000318ae0, 0xc000668180, 0xc0004db880)
	pkg/log/log.go:259 +0xb6
gvisor.googlesource.com/gvisor/runsc/boot.(*debug).Stacks(0x2427e60, 0x2427e60, 0xc00079c010, 0x0, 0x0)
	runsc/boot/debug.go:26 +0x38
reflect.Value.call(0xc000318ae0, 0xc0003361c0, 0x13, 0x115a58b, 0x4, 0xc00079feb8, 0x3, 0x3, 0x4a864e, 0x10074e0, ...)
	GOROOT/src/reflect/value.go:447 +0x649
reflect.Value.Call(0xc000318ae0, 0xc0003361c0, 0x13, 0xc00079feb8, 0x3, 0x3, 0x0, 0x2427e60, 0x16)
	GOROOT/src/reflect/value.go:308 +0xc1
gvisor.googlesource.com/gvisor/pkg/urpc.(*Server).handleOne(0xc0002c6150, 0xc0001b0360, 0x0, 0x0)
	pkg/urpc/urpc.go:325 +0x63f
gvisor.googlesource.com/gvisor/pkg/urpc.(*Server).handleRegistered(0xc0002c6150, 0xc0001b0360, 0xc0002c6150, 0xc0001b0360)
	pkg/urpc/urpc.go:420 +0x43
gvisor.googlesource.com/gvisor/pkg/urpc.(*Server).StartHandling.func1(0xc0002c6150, 0xc0001b0360)
	pkg/urpc/urpc.go:440 +0x77
created by gvisor.googlesource.com/gvisor/pkg/urpc.(*Server).StartHandling
	pkg/urpc/urpc.go:438 +0x6f

goroutine 1 [semacquire]:
sync.runtime_Semacquire(0xc0002d8084)
	GOROOT/src/runtime/sema.go:56 +0x39
sync.(*WaitGroup).Wait(0xc0002d8084)
	GOROOT/src/sync/waitgroup.go:130 +0xb2
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Kernel).WaitExited(...)
	pkg/sentry/kernel/kernel.go:896
gvisor.googlesource.com/gvisor/runsc/boot.(*Loader).WaitExit(0xc000234280, 0x0, 0x0)
	runsc/boot/loader.go:785 +0x74
gvisor.googlesource.com/gvisor/runsc/cmd.(*Boot).Execute(0xc000250090, 0x12f0300, 0xc0000ce008, 0xc00024a540, 0xc00026a160, 0x2, 0x2, 0x0)
	runsc/cmd/boot.go:252 +0x12e4
github.com/google/subcommands.(*Commander).Execute(0xc000132000, 0x12f0300, 0xc0000ce008, 0xc00026a160, 0x2, 0x2, 0xc000268580)
	external/com_github_google_subcommands/subcommands.go:141 +0x522
github.com/google/subcommands.Execute(...)
	external/com_github_google_subcommands/subcommands.go:371
main.main()
	runsc/main.go:245 +0x254e