panic: Decrementing non-positive ref count goroutine 3633820 [running]: gvisor.googlesource.com/gvisor/pkg/refs.(*AtomicRefCount).DecRefWithDestructor(0xc42018be00, 0xc421711d58) pkg/refs/refcounter.go:271 +0x162 gvisor.googlesource.com/gvisor/pkg/sentry/kernel/shm.(*Shm).DecRef(0xc42018be00) pkg/sentry/kernel/shm/shm.go:359 +0x48 gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).removeVMAsLocked(0xc42071d900, 0xc691e0, 0xc421f743c0, 0x10000, 0x7fffffff0000, 0x66e59d, 0xc421711e48) pkg/sentry/mm/vma.go:338 +0x1a4 gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).unmapLocked(0xc42071d900, 0xc691e0, 0xc421f743c0, 0x10000, 0x7fffffff0000, 0x18, 0xc4218624c0) pkg/sentry/mm/vma.go:310 +0x7e gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).DecUsers(0xc42071d900, 0xc691e0, 0xc421f743c0) pkg/sentry/mm/lifecycle.go:220 +0x1dd gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*TaskContext).release(0xc421319930) pkg/sentry/kernel/task_context.go:64 +0xd6 gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*runExitMain).execute(0x0, 0xc421319200, 0xc5bc00, 0x0) pkg/sentry/kernel/task_exit.go:266 +0xc5 gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).run(0xc421319200, 0x38c0) pkg/sentry/kernel/task_run.go:95 +0x174 created by gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).Start pkg/sentry/kernel/task_start.go:258 +0x100