unslop some comments

overlay/tio/blockon_linux.go

@@ -12,15 +12,10 @@ import (
 // blockOn parks the calling goroutine until fd is ready (events is POLLIN for
 // reads, POLLOUT for writes) or shutdownFd signals teardown. It builds the
 // pollfd array on the stack every call, so concurrent callers on the same
-// Queue never share Revents storage: the previous shared-array implementation
-// was a genuine Go data race when two writers parked in poll(2) at once (the
-// kernel writing Revents while another goroutine zeroed it). Level-triggered
-// events kept it from deadlocking, but it was still a race.
+// Queue never share Revents storage.
 //
-// Poll(2) is looped over EINTR. err is checked before the Revents bits are
-// trusted, since a failed poll may leave them bogus. Returns os.ErrClosed when
-// shutdown was signaled (POLLIN on shutdownFd) or either fd reported a problem
-// condition (POLLHUP|POLLNVAL|POLLERR).
+// Returns os.ErrClosed when shutdown was signaled (POLLIN on shutdownFd)
+// or either fd reported a problem condition (POLLHUP|POLLNVAL|POLLERR).
 func blockOn(fd, shutdownFd int32, events int16) error {
 	const problemFlags = unix.POLLHUP | unix.POLLNVAL | unix.POLLERR
 	pfds := [2]unix.PollFd{