Explicitly emphasize a facet of m_pullup() that some people seem to

frequently forget. i.e. that you can not keep using pointers to
within the old chain.

1 files changed, 4 insertions, 0 deletions

diff --git a/share/man/man9/mbuf.9 b/share/man/man9/mbuf.9
index e2d3865..dc98b02 100644
--- a/share/man/man9/mbuf.9
+++ b/share/man/man9/mbuf.9
@@ -643,6 +643,10 @@ are contiguous and lay in the data area of
 .Fa mbuf ,
 so they are accessible with
 .Fn mtod mbuf type .
+It is important to remember that this may involve
+reallocating some mbufs and moving data so all pointers
+referencing data within the old mbuf chain
+must be recalculated or made invalid.
 Return the new
 .Vt mbuf chain
 on success,