diff --git a/Documentation/devices.txt b/Documentation/devices.txt
index 8de132a02ba952..6c46730c631a69 100644
--- a/Documentation/devices.txt
+++ b/Documentation/devices.txt
@@ -94,6 +94,8 @@ Your cooperation is appreciated.
 		  9 = /dev/urandom	Faster, less secure random number gen.
 		 10 = /dev/aio		Asynchronous I/O notification interface
 		 11 = /dev/kmsg		Writes to this come out as printk's
+		 12 = /dev/oldmem	Used by crashdump kernels to access
+					the memory of the kernel that crashed.
 
   1 block	RAM disk
 		  0 = /dev/ram0		First RAM disk