docs: add info on why eip and esp are zeroed out

diff --git a/man/ps.1 b/man/ps.1
index 9ca5a6c0c4a47568c00f27242da7a3a67e4ac425..dabfcfdc6ec07ac16330b5d2b05387fb98ae4c10 100644 (file)
--- a/man/ps.1
+++ b/man/ps.1
@@ -1258,11 +1258,13 @@ otherwise.  (alias
 T}
 
 eip    EIP     T{
-instruction pointer.
+instruction pointer. As of kernel 4.9.xx will be zeroed out unless task is 
+exiting or being core dumped.
 T}
 
 esp    ESP     T{
-stack pointer.
+stack pointer. As of kernel 4.9.xx will be zeroed out unless task is 
+exiting or being core dumped.
 T}
 
 etime  ELAPSED T{