diff --git a/sys/conf/NOTES b/sys/conf/NOTES
index bd52cf0a6766..fbc2d0eecd50 100644
--- a/sys/conf/NOTES
+++ b/sys/conf/NOTES
@@ -2574,6 +2574,9 @@ options 	SPX_HACK
 # Enable Linux ABI emulation
 options 	COMPAT_LINUX
 
+# Enable the linux-like proc filesystem support (requires COMPAT_LINUX)
+options 	LINPROCFS
+
 # Linux debugging
 options 	DEBUG_LINUX
 
diff --git a/sys/i386/conf/NOTES b/sys/i386/conf/NOTES
index bd52cf0a6766..fbc2d0eecd50 100644
--- a/sys/i386/conf/NOTES
+++ b/sys/i386/conf/NOTES
@@ -2574,6 +2574,9 @@ options 	SPX_HACK
 # Enable Linux ABI emulation
 options 	COMPAT_LINUX
 
+# Enable the linux-like proc filesystem support (requires COMPAT_LINUX)
+options 	LINPROCFS
+
 # Linux debugging
 options 	DEBUG_LINUX