fatal error: unknown caller pc (2)

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
gvisor	fatal error: unknown caller pc				1	1875d	1868d	0/26	auto-closed as invalid on 2020/01/06 21:50
gvisor	fatal error: unknown caller pc (3)	C			126	837d	1451d	0/26	moderation: reported C repro on 2020/12/06 08:32

fatal error: unknown caller pc DIAGNOSIS: I0229 00:55:07.183700 53515 main.go:305] *************************** I0229 00:55:07.183751 53515 main.go:306] Args: [/syzkaller/managers/ptrace-direct-overlay-host/current/image -root /syzkaller/managers/ptrace-direct-overlay-host/workdir/gvisor_root -watchdog-action=panic -network=none -debug -alsologtostderr -platform=ptrace -file-access=shared -network=host debug -stacks --ps ci-gvisor-ptrace-direct-overlay-host-1] I0229 00:55:07.183799 53515 main.go:307] Version release-20200219.0-72-gce4d1e45bb88 I0229 00:55:07.183817 53515 main.go:308] PID: 53515 I0229 00:55:07.183836 53515 main.go:309] UID: 0, GID: 0 I0229 00:55:07.183855 53515 main.go:310] Configuration: I0229 00:55:07.183871 53515 main.go:311] RootDir: /syzkaller/managers/ptrace-direct-overlay-host/workdir/gvisor_root I0229 00:55:07.183924 53515 main.go:312] Platform: ptrace I0229 00:55:07.183956 53515 main.go:313] FileAccess: shared, overlay: false I0229 00:55:07.183981 53515 main.go:314] Network: host, logging: false I0229 00:55:07.184000 53515 main.go:315] Strace: false, max size: 1024, syscalls: [] I0229 00:55:07.184030 53515 main.go:316] *************************** D0229 00:55:07.184075 53515 container.go:159] Load container "/syzkaller/managers/ptrace-direct-overlay-host/workdir/gvisor_root" "ci-gvisor-ptrace-direct-overlay-host-1" D0229 00:55:07.185349 53515 container.go:592] Signal container "ci-gvisor-ptrace-direct-overlay-host-1": signal 0 D0229 00:55:07.185384 53515 sandbox.go:806] Signal sandbox "ci-gvisor-ptrace-direct-overlay-host-1" D0229 00:55:07.185399 53515 sandbox.go:318] Connecting to sandbox "ci-gvisor-ptrace-direct-overlay-host-1" D0229 00:55:07.185556 53515 urpc.go:534] urpc: successfully marshalled 118 bytes. I0229 00:55:07.443657 53515 debug.go:122] Found sandbox "ci-gvisor-ptrace-direct-overlay-host-1", PID: 45362 I0229 00:55:07.443749 53515 debug.go:131] Retrieving sandbox stacks D0229 00:55:07.443776 53515 sandbox.go:924] Stacks sandbox "ci-gvisor-ptrace-direct-overlay-host-1" D0229 00:55:07.443792 53515 sandbox.go:318] Connecting to sandbox "ci-gvisor-ptrace-direct-overlay-host-1" W0229 00:55:07.443840 53515 error.go:48] FATAL ERROR: retrieving stacks: connecting to control server at PID 45362: connection refused retrieving stacks: connecting to control server at PID 45362: connection refused W0229 00:55:07.444073 53515 main.go:338] Failure to execute command, err: 1