panic: WARNING: circular locking detected: kernel.fsContextMutex -> kernfs.filesystemRWMutex: goroutine 679 [running]: gvisor.dev/gvisor/pkg/sync/locking.(*ancestorsAtomicPtrMap).RangeRepeatable(0xc000306c80, 0xc000be7138) bazel-out/k8-fastbuild/bin/pkg/sync/locking/atomicptrmap_ancestors_unsafe.go:440 +0x314 gvisor.dev/gvisor/pkg/sync/locking.checkLock(0xc0001bccf0, 0xc000306c60, {0x0, 0x0, 0x0}) pkg/sync/locking/lockdep.go:112 +0x4eb gvisor.dev/gvisor/pkg/sync/locking.AddGLock(0xc0001bccf0, 0xffffffffffffffff) pkg/sync/locking/lockdep.go:144 +0x37b gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*filesystemRWMutex).Lock(0xc000e807d0) bazel-out/k8-fastbuild/bin/pkg/sentry/fsimpl/kernfs/filesystem_mutex.go:31 +0x4d gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*Dentry).DecRef(0xc000701c20, {0x21bc6b0, 0xc00108e588}) pkg/sentry/fsimpl/kernfs/kernfs.go:303 +0x116 gvisor.dev/gvisor/pkg/sentry/vfs.(*Dentry).DecRef(0xc000701c20, {0x21bc6b0, 0xc00108e588}) pkg/sentry/vfs/dentry.go:156 +0x68 gvisor.dev/gvisor/pkg/sentry/vfs.VirtualDentry.DecRef({0xc000223340?, 0xc000701c20?}, {0x21bc6b0, 0xc00108e588}) pkg/sentry/vfs/vfs.go:1114 +0x5b gvisor.dev/gvisor/pkg/sentry/kernel.(*FSContext).SetWorkingDirectory(0xc0009929c0, {0x21bc6b0, 0xc00108e588}, {0xc000223340, 0xc000c1f560}) pkg/sentry/kernel/fs_context.go:144 +0x23b gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Fchdir(0xc00108e588, 0xca?, {{0x3}, {0x0}, {0x0}, {0x0}, {0x0}, {0x0}}) pkg/sentry/syscalls/linux/sys_file.go:361 +0x3b8 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc00108e588, 0x51, {{0x3}, {0x0}, {0x0}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:143 +0xb90 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc00108e588, 0x51, {{0x3}, {0x0}, {0x0}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:323 +0x85 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc00108e588, 0x51, {{0x3}, {0x0}, {0x0}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:283 +0xc7 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc00108e588) pkg/sentry/kernel/task_syscall.go:258 +0x53e gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0xc00108e588?, 0xc00108e588) pkg/sentry/kernel/task_run.go:269 +0x220c gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc00108e588, 0x4e) pkg/sentry/kernel/task_run.go:97 +0x402 created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start in goroutine 666 pkg/sentry/kernel/task_start.go:416 +0x17e known lock chain: kernfs.filesystemRWMutex -> kernel.taskMutex -> kernel.fsContextMutex ====== kernfs.filesystemRWMutex -> kernel.taskMutex ===== goroutine 258 [running]: gvisor.dev/gvisor/pkg/sentry/kernel.(*taskMutex).Lock(0xc0005349a0) bazel-out/k8-fastbuild/bin/pkg/sentry/kernel/task_mutex.go:35 +0x4d gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).GetNetworkNamespace(0xc000534008) pkg/sentry/kernel/task_net.go:48 +0x4d gvisor.dev/gvisor/pkg/sentry/fsimpl/proc.(*filesystem).newTaskNetDir(0xc0009f6300, {0x21bc6b0, 0xc000534008}, 0xc000534008) pkg/sentry/fsimpl/proc/task_net.go:47 +0x132 gvisor.dev/gvisor/pkg/sentry/fsimpl/proc.(*filesystem).newTaskInode(0xc0009f6300, {0x21bc6b0, 0xc000534008}, 0xc000534008, 0xc00047eee0, 0x1, 0x0) pkg/sentry/fsimpl/proc/task.go:77 +0x12d3 gvisor.dev/gvisor/pkg/sentry/fsimpl/proc.(*tasksInode).Lookup(0xc00077f008, {0x21bc6b0, 0xc000534008}, {0x1fa44d4, 0x1}) pkg/sentry/fsimpl/proc/tasks.go:147 +0x3c6 gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*Filesystem).revalidateChildLocked(0xc0009f6300, {0x21bc6b0, 0xc000534008}, 0xc0000049e0, 0xc0006feea0, {0x1fa44d4, 0x1}) pkg/sentry/fsimpl/kernfs/filesystem.go:127 +0x3eb gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*Filesystem).stepExistingLocked(0xc0009f6300, {0x21bc6b0, 0xc000534008}, 0xc0002abb08, 0xc0006feea0) pkg/sentry/fsimpl/kernfs/filesystem.go:74 +0x459 gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*Filesystem).walkExistingLocked(0xc0009f6300, {0x21bc6b0, 0xc000534008}, 0xc0002abb08) pkg/sentry/fsimpl/kernfs/filesystem.go:197 +0x106 gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*Filesystem).ReadlinkAt(0xc0009f6300, {0x21bc6b0, 0xc000534008}, 0xc0002abb08) pkg/sentry/fsimpl/kernfs/filesystem.go:697 +0x14a gvisor.dev/gvisor/pkg/sentry/vfs.(*VirtualFilesystem).ReadlinkAt(0xc0000049e0, {0x21bc6b0, 0xc000534008}, 0xc0001684e0, 0xc000c19598) pkg/sentry/vfs/vfs.go:512 +0x109 gvisor.dev/gvisor/pkg/sentry/syscalls/linux.readlinkat(0xc000534008, 0xffffff9c, 0xc000184070, 0xc000196d00, 0x80) pkg/sentry/syscalls/linux/sys_file.go:1096 +0x305 gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Readlinkat(0xc000534008, 0xca?, {{0xffffffffffffff9c}, {0xc000184070}, {0xc000196d00}, {0x80}, {0x0}, {0x0}}) pkg/sentry/syscalls/linux/sys_file.go:1067 +0xc6 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc000534008, 0x10b, {{0xffffffffffffff9c}, {0xc000184070}, {0xc000196d00}, {0x80}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:143 +0xb90 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc000534008, 0x10b, {{0xffffffffffffff9c}, {0xc000184070}, {0xc000196d00}, {0x80}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:323 +0x85 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc000534008, 0x10b, {{0xffffffffffffff9c}, {0xc000184070}, {0xc000196d00}, {0x80}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:283 +0xc7 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc000534008) pkg/sentry/kernel/task_syscall.go:258 +0x53e gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0xc000534008?, 0xc000534008) pkg/sentry/kernel/task_run.go:269 +0x220c gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc000534008, 0x1) pkg/sentry/kernel/task_run.go:97 +0x402 created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start in goroutine 1 pkg/sentry/kernel/task_start.go:416 +0x17e ====== kernel.taskMutex -> kernel.fsContextMutex ===== goroutine 311 [running]: gvisor.dev/gvisor/pkg/sentry/kernel.(*fsContextMutex).Lock(0xc000c75748) bazel-out/k8-fastbuild/bin/pkg/sentry/kernel/fs_context_mutex.go:33 +0x4d gvisor.dev/gvisor/pkg/sentry/kernel.(*FSContext).Fork(0xc000c75740) pkg/sentry/kernel/fs_context.go:97 +0x65 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Unshare(0xc000d4c008, 0x20000) pkg/sentry/kernel/task_clone.go:706 +0x1207 gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Unshare(0xc000d4c008, 0x489e31?, {{0x20000}, {0x7}, {0x7ef98af2baf0}, {0x0}, {0x0}, {0x5557863256c0}}) pkg/sentry/syscalls/linux/sys_thread.go:453 +0xd5 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc000d4c008, 0x110, {{0x20000}, {0x7}, {0x7ef98af2baf0}, {0x0}, {0x0}, {0x5557863256c0}}) pkg/sentry/kernel/task_syscall.go:143 +0xb90 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc000d4c008, 0x110, {{0x20000}, {0x7}, {0x7ef98af2baf0}, {0x0}, {0x0}, {0x5557863256c0}}) pkg/sentry/kernel/task_syscall.go:323 +0x85 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc000d4c008, 0x110, {{0x20000}, {0x7}, {0x7ef98af2baf0}, {0x0}, {0x0}, {0x5557863256c0}}) pkg/sentry/kernel/task_syscall.go:283 +0xc7 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc000d4c008) pkg/sentry/kernel/task_syscall.go:258 +0x53e gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0xc000d4c008?, 0xc000d4c008) pkg/sentry/kernel/task_run.go:269 +0x220c gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc000d4c008, 0x19) pkg/sentry/kernel/task_run.go:97 +0x402 created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start in goroutine 287 pkg/sentry/kernel/task_start.go:416 +0x17e