vmm: add a safety comment for EpollContext
@@ -178,6 +178,7 @@ impl EpollContext {
pub fn new() -> result::Result<EpollContext, io::Error> {
let epoll_fd = epoll::create(true)?;
// Use 'File' to enforce closing on 'epoll_fd'
+ // SAFETY: the epoll_fd returned by epoll::create is valid and owned by us.
let epoll_file = unsafe { File::from_raw_fd(epoll_fd) };
Ok(EpollContext { epoll_file })
