[master] 1d2175b5a doc: Mention noexec and workdir

[Nils Goroll]

commit 1d2175b5af7e3fe5f4436f0ee143dbe5451f7058
Author: Nils Goroll <nils.goroll at uplex.de>
Date:   Mon Feb 3 15:54:12 2025 +0100

    doc: Mention noexec and workdir
    
    Ref #3943

diff --git a/doc/sphinx/installation/platformnotes.rst b/doc/sphinx/installation/platformnotes.rst
index d9a77ad08..eee80f795 100644
--- a/doc/sphinx/installation/platformnotes.rst
+++ b/doc/sphinx/installation/platformnotes.rst
@@ -35,6 +35,12 @@ Otherwise, consider creating a ``tmpfs`` mountpoint at *workdir*, or configure
 Note: Very valid reasons exist for *not* following this recommendation, if you
 know what you are doing.
 
+workdir can not be mounted ``noexec``
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Varnish compiles VCL to a shared object and needs to load it at runtime. So the
+workdie can not reside on a file system mounted with ``noexec``.
+
 Lift locked memory limits
 ~~~~~~~~~~~~~~~~~~~~~~~~~