diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index 9c55077..3c36c93 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -748,6 +748,10 @@
    CPU. This needs to be enabled for revisions r0p0 and r1p0, it is fixed in
    r2p0.
 
+-  ``ERRATA_X2_1917258``: This applies errata 1917258 workaround to Cortex-X2
+   CPU. This needs to be enabled for revisions r0p0 and r1p0, it is fixed in
+   r2p0.
+
 -  ``ERRATA_X2_2002765``: This applies errata 2002765 workaround to Cortex-X2
    CPU. This needs to be enabled for revisions r0p0, r1p0, and r2p0 of the CPU,
    it is still open.