clarify an edge case of IORING_SETUP_SQ_AFF
A container may offen be migrated to different cpu set which causes the
bounded cpu set of sqthread being changed as well. This may not be as
users expected, clarify this situation in man page.
@@ -139,7 +139,10 @@ field of the
.IR "struct io_uring_params" .
This flag is only meaningful when
.B IORING_SETUP_SQPOLL
-is specified.
+is specified. When cgroup setting
+.I cpuset.cpus
+changes (typically in container environment), the bounded cpu set may be
+changed as well.
.TP
.B IORING_SETUP_CQSIZE
Create the completion queue with
