diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml
index d2279a9b9a..8be6a1aadd 100644
--- a/man/systemd.exec.xml
+++ b/man/systemd.exec.xml
@@ -863,12 +863,17 @@ CapabilityBoundingSet=~CAP_B CAP_C
Controls the file mode creation mask. Takes an access mode in octal notation. See
umask2 for
- details. Defaults to 0022 for system units. For units of the user service manager the default value
- is inherited from the user instance (whose default is inherited from the system service manager, and
- thus also is 0022). Hence changing the default value of a user instance, either via
- UMask= or via a PAM module, will affect the user instance itself and all user
- units started by the user instance unless a user unit has specified its own
- UMask=.
+ details. Defaults to 0022 for system units. For user units the default value is inherited from the
+ per-user service manager (whose default is in turn inherited from the system service manager, and
+ thus typically also is 0022 — unless overriden by a PAM module). In order to change the per-user mask
+ for all user services, consider setting the UMask= setting of the user's
+ user@.service system service instance. The per-user umask may also be set via
+ the umask field of a user's JSON User
+ Record (for users managed by
+ systemd-homed.service8
+ this field may be controlled via homectl --umask=). It may also be set via a PAM
+ module, such as pam_umask8.