diff --git a/releases/4.0/release-notes.md b/releases/4.0/release-notes.md
index fedfde6c..d51a4baf 100644
--- a/releases/4.0/release-notes.md
+++ b/releases/4.0/release-notes.md
@@ -31,6 +31,10 @@ New features since 3.2
 
 You can get detailed description in [completed github issues][github-release-notes]
 
+Note
+----
+* PV VMs restored from R3.2 to R4.x will be automatically migrated to PVH from R4.rc4 to address [QSB 37 (Meltdown & Spectre)][qsb-37]. However PV VMs restored from R4.x are not migrated.
+
 Known issues
 ------------
 
@@ -40,6 +44,8 @@ Known issues
 
 * For other known issues take a look at [our tickets](https://github.com/QubesOS/qubes-issues/issues?q=is%3Aopen+is%3Aissue+milestone%3A%22Release+4.0%22+label%3Abug)
 
+* Until R4.rc3 included, PV VMs restored from R3.x backup will not automatically be migrated to PVH mode and may be exposed to [QSB 37][qsb-37].
+
 It is advised to install updates just after system installation to apply bug fixes for (some of) the above problems.
 
 Downloads
@@ -76,6 +82,7 @@ We also provide [detailed instruction][upgrade-to-r4.0] for this procedure.
 [vm-interface]: /doc/vm-interface/
 [admin-api]: /news/2017/06/27/qubes-admin-api/
 [qsb-24]: https://github.com/QubesOS/qubes-secpack/blob/master/QSBs/qsb-024-2016.txt
+[qsb-37]: https://www.qubes-os.org/news/2018/01/24/qsb-37-update/
 [backup-format]: /doc/backup-emergency-restore-v4/
 [api-doc]: https://dev.qubes-os.org/projects/qubes-core-admin/en/latest/
 [upgrade-to-r4.0]: /doc/upgrade-to-r4.0/