panic: nested locking: kernfs.filesystemRWMutex: goroutine 811818 [running]: gvisor.dev/gvisor/pkg/log.Stacks(0x40?) pkg/log/log.go:318 +0x8d gvisor.dev/gvisor/pkg/sync/locking.AddGLock(0xc0001bf400, 0x0) pkg/sync/locking/lockdep.go:105 +0x4dd gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*filesystemRWMutex).Lock(0xc0001c4230) bazel-out/k8-fastbuild-ST-3dcbe13c9b87/bin/pkg/sentry/fsimpl/kernfs/filesystem_mutex.go:18 +0x3f gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*Dentry).DecRef(0xc003723a70, {0x1bd2c70, 0xc00694d500}) pkg/sentry/fsimpl/kernfs/kernfs.go:282 +0x79 gvisor.dev/gvisor/pkg/sentry/vfs.(*Dentry).DecRef(...) pkg/sentry/vfs/dentry.go:161 gvisor.dev/gvisor/pkg/sentry/vfs.VirtualDentry.DecRef({0xc0001ba3c0?, 0xc003723a70?}, {0x1bd2c70, 0xc00694d500}) pkg/sentry/vfs/vfs.go:914 +0x75 gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescription).DecRef.func1() pkg/sentry/vfs/file_description.go:196 +0x394 gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescriptionRefs).DecRef(0xc0006ebbc0, 0xc000dce938) bazel-out/k8-fastbuild-ST-3dcbe13c9b87/bin/pkg/sentry/vfs/file_description_refs.go:131 +0x5f gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescription).DecRef(0xc0006ebbc0, {0x1bd2c70, 0xc00694d500}) pkg/sentry/vfs/file_description.go:161 +0x6f gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*Filesystem).SafeDecRefFD(0xc0001c45a0, {0x1bd2c70, 0xc00694d500}, 0xc0006ebbc0) pkg/sentry/fsimpl/kernfs/kernfs.go:153 +0xb3 gvisor.dev/gvisor/pkg/sentry/fsimpl/proc.taskFDExists({0x1bd2c70, 0xc00694d500}, 0xc0001c45a0, 0x416d0001?, 0x0?) pkg/sentry/fsimpl/proc/task_fds.go:50 +0x69 gvisor.dev/gvisor/pkg/sentry/fsimpl/proc.(*fdSymlink).Valid(0xc0059f7bc0, {0x1bd2c70, 0xc00694d500}) pkg/sentry/fsimpl/proc/task_fds.go:244 +0x94 gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*Filesystem).revalidateChildLocked(0x16de680?, {0x1bd2c70, 0xc00694d500}, 0x1?, 0xc0008b3e60, {0xc00271d00e, 0x1}, 0xc0008b3ef0) pkg/sentry/fsimpl/kernfs/filesystem.go:121 +0xa7 gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*Filesystem).stepExistingLocked(0xc000dcec18?, {0x1bd2c70, 0xc00694d500}, 0xc000643680, 0xc0008b3e60, 0x1) pkg/sentry/fsimpl/kernfs/filesystem.go:76 +0x2ae gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*Filesystem).walkExistingLocked(0xc0001c45f0?, {0x1bd2c70, 0xc00694d500}, 0xc000643680) pkg/sentry/fsimpl/kernfs/filesystem.go:166 +0xd9 gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*Filesystem).OpenAt(0xc0001c45a0, {0x1bd2c70, 0xc00694d500}, 0xc000643680, {0x2, 0x0, 0x0}) pkg/sentry/fsimpl/kernfs/filesystem.go:490 +0x1cd gvisor.dev/gvisor/pkg/sentry/vfs.(*VirtualFilesystem).OpenAt(0xc005f91360?, {0x1bd2c70, 0xc00694d500}, 0xc000381b00?, 0xc000dcf3e8, 0xc000dcf2e0) pkg/sentry/vfs/vfs.go:428 +0x4ef gvisor.dev/gvisor/pkg/sentry/syscalls/linux/vfs2.openat(0xc00694d500, 0x0?, 0x470ec5?, 0x2, 0x0) pkg/sentry/syscalls/linux/vfs2/filesystem.go:179 +0x2aa gvisor.dev/gvisor/pkg/sentry/syscalls/linux/vfs2.Openat(0xc00694d500?, {{0xffffff9c}, {0x7fae6d3680d0}, {0x2}, {0x0}, {0x0}, {0x7fae6d367f50}}) pkg/sentry/syscalls/linux/vfs2/filesystem.go:158 +0x45 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc00694d500, 0x101, {{0xffffff9c}, {0x7fae6d3680d0}, {0x2}, {0x0}, {0x0}, {0x7fae6d367f50}}) pkg/sentry/kernel/task_syscall.go:142 +0xa78 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc00694d500, 0x0?, {{0xffffff9c}, {0x7fae6d3680d0}, {0x2}, {0x0}, {0x0}, {0x7fae6d367f50}}) pkg/sentry/kernel/task_syscall.go:322 +0x7d gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc0038c1930?, 0xc0034b7590?, {{0xffffff9c}, {0x7fae6d3680d0}, {0x2}, {0x0}, {0x0}, {0x7fae6d367f50}}) pkg/sentry/kernel/task_syscall.go:282 +0x8f gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc00694d500) pkg/sentry/kernel/task_syscall.go:257 +0x496 gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0xc00694d500?, 0xc00694d500) pkg/sentry/kernel/task_run.go:253 +0x18f9 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc00694d500, 0x91c9) pkg/sentry/kernel/task_run.go:94 +0x354 created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start pkg/sentry/kernel/task_start.go:370 +0x1a8