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

goroutine 1212337 [running]:
DIAGNOSIS:
I1017 10:14:23.693120   20997 x:0] ***************************
I1017 10:14:23.693316   20997 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 ci-gvisor-ptrace-direct-overlay-host-race-0]
I1017 10:14:23.693458   20997 x:0] Version release-20190806.1-283-g2a82d5ad68de
I1017 10:14:23.693493   20997 x:0] PID: 20997
I1017 10:14:23.693541   20997 x:0] UID: 0, GID: 0
I1017 10:14:23.693583   20997 x:0] Configuration:
I1017 10:14:23.693607   20997 x:0] 		RootDir: /syzkaller/managers/ptrace-direct-overlay-host-race/workdir/gvisor_root
I1017 10:14:23.693652   20997 x:0] 		Platform: ptrace
I1017 10:14:23.693690   20997 x:0] 		FileAccess: exclusive, overlay: true
I1017 10:14:23.693746   20997 x:0] 		Network: host, logging: false
I1017 10:14:23.693797   20997 x:0] 		Strace: false, max size: 1024, syscalls: []
I1017 10:14:23.693859   20997 x:0] ***************************
W1017 10:14:23.693901   20997 x:0] Block the TERM signal. This is only safe in tests!
D1017 10:14:23.694047   20997 x:0] Load container "/syzkaller/managers/ptrace-direct-overlay-host-race/workdir/gvisor_root" "ci-gvisor-ptrace-direct-overlay-host-race-0"
D1017 10:14:23.701600   20997 x:0] Signal container "ci-gvisor-ptrace-direct-overlay-host-race-0": signal 0
D1017 10:14:23.701739   20997 x:0] Signal sandbox "ci-gvisor-ptrace-direct-overlay-host-race-0"
D1017 10:14:23.701806   20997 x:0] Connecting to sandbox "ci-gvisor-ptrace-direct-overlay-host-race-0"
D1017 10:14:23.702297   20997 x:0] urpc: successfully marshalled 123 bytes.
I1017 10:14:24.034656   20997 x:0] Found sandbox "ci-gvisor-ptrace-direct-overlay-host-race-0", PID: 60554
I1017 10:14:24.034803   20997 x:0] Retrieving sandbox stacks
D1017 10:14:24.034852   20997 x:0] Stacks sandbox "ci-gvisor-ptrace-direct-overlay-host-race-0"
D1017 10:14:24.034936   20997 x:0] Connecting to sandbox "ci-gvisor-ptrace-direct-overlay-host-race-0"
D1017 10:14:24.035145   20997 x:0] urpc: successfully marshalled 36 bytes.
W1017 10:14:24.082665   20997 x:0] FATAL ERROR: retrieving stacks: getting sandbox "ci-gvisor-ptrace-direct-overlay-host-race-0" stacks: urpc method "debug.Stacks" failed: connection reset by peer
retrieving stacks: getting sandbox "ci-gvisor-ptrace-direct-overlay-host-race-0" stacks: urpc method "debug.Stacks" failed: connection reset by peer
W1017 10:14:24.082962   20997 x:0] Failure to execute command, err: 1