panic: munmap(7fcf4f000000, 200000)) failed: function not implemented
DIAGNOSIS:
I1226 14:11:39.193815    3556 x:0] ***************************
I1226 14:11:39.193867    3556 x:0] Args: [/syzkaller/managers/ptrace-direct-overlay-host-race/current/image -root /syzkaller/managers/ptrace-direct-overlay-host-race/workdir/gvisor_root -watchdog-action=panic -network=none -debug -alsologtostderr -platform=ptrace -file-access=exclusive -overlay -network=host -TESTONLY-unsafe-nonroot debug -stacks --ps ci-gvisor-ptrace-direct-overlay-host-race-3]
I1226 14:11:39.193993    3556 x:0] Version release-20191213.0-48-ge013c48c78c9
I1226 14:11:39.194037    3556 x:0] PID: 3556
I1226 14:11:39.194078    3556 x:0] UID: 0, GID: 0
I1226 14:11:39.194115    3556 x:0] Configuration:
I1226 14:11:39.194142    3556 x:0] 		RootDir: /syzkaller/managers/ptrace-direct-overlay-host-race/workdir/gvisor_root
I1226 14:11:39.194179    3556 x:0] 		Platform: ptrace
I1226 14:11:39.194213    3556 x:0] 		FileAccess: exclusive, overlay: true
I1226 14:11:39.194260    3556 x:0] 		Network: host, logging: false
I1226 14:11:39.194301    3556 x:0] 		Strace: false, max size: 1024, syscalls: []
I1226 14:11:39.194342    3556 x:0] ***************************
W1226 14:11:39.194379    3556 x:0] Block the TERM signal. This is only safe in tests!
D1226 14:11:39.194515    3556 x:0] Load container "/syzkaller/managers/ptrace-direct-overlay-host-race/workdir/gvisor_root" "ci-gvisor-ptrace-direct-overlay-host-race-3"
D1226 14:11:39.203485    3556 x:0] Signal container "ci-gvisor-ptrace-direct-overlay-host-race-3": signal 0
D1226 14:11:39.203606    3556 x:0] Signal sandbox "ci-gvisor-ptrace-direct-overlay-host-race-3"
D1226 14:11:39.203682    3556 x:0] Connecting to sandbox "ci-gvisor-ptrace-direct-overlay-host-race-3"
D1226 14:11:39.204133    3556 x:0] urpc: successfully marshalled 123 bytes.
I1226 14:11:39.709323    3556 x:0] Found sandbox "ci-gvisor-ptrace-direct-overlay-host-race-3", PID: 27730
I1226 14:11:39.709580    3556 x:0] Retrieving sandbox stacks
D1226 14:11:39.709650    3556 x:0] Stacks sandbox "ci-gvisor-ptrace-direct-overlay-host-race-3"
D1226 14:11:39.709756    3556 x:0] Connecting to sandbox "ci-gvisor-ptrace-direct-overlay-host-race-3"
D1226 14:11:39.709935    3556 x:0] urpc: successfully marshalled 36 bytes.
W1226 14:11:39.797651    3556 x:0] FATAL ERROR: retrieving stacks: getting sandbox "ci-gvisor-ptrace-direct-overlay-host-race-3" stacks: urpc method "debug.Stacks" failed: connection reset by peer
retrieving stacks: getting sandbox "ci-gvisor-ptrace-direct-overlay-host-race-3" stacks: urpc method "debug.Stacks" failed: connection reset by peer
W1226 14:11:39.797902    3556 x:0] Failure to execute command, err: 1