diff --git a/elf/dl-tunables.list b/elf/dl-tunables.list
index 0d398dd251..92b6f21b44 100644
--- a/elf/dl-tunables.list
+++ b/elf/dl-tunables.list
@@ -126,4 +126,13 @@ glibc {
       default: 3
     }
   }
+
+  memtag {
+    enable {
+      type: INT_32
+      minval: 0
+      maxval: 255
+      env_alias: _MTAG_ENABLE
+    }
+  }
 }
diff --git a/manual/tunables.texi b/manual/tunables.texi
index ec18b10834..428a0918e6 100644
--- a/manual/tunables.texi
+++ b/manual/tunables.texi
@@ -35,6 +35,8 @@ their own namespace.
 * POSIX Thread Tunables:: Tunables in the POSIX thread subsystem
 * Hardware Capability Tunables::  Tunables that modify the hardware
 				  capabilities seen by @theglibc{}
+* Memory Tagging Tunables::  Tunables that control the use of hardware
+			     memory tagging
 @end menu
 
 @node Tunable names
@@ -423,3 +425,32 @@ instead.
 
 This tunable is specific to i386 and x86-64.
 @end deftp
+
+@node Memory Tagging Tunables
+@section Memory Tagging Tunables
+@cindex memory tagging tunables
+
+@deftp {Tunable namespace} glibc.memtag
+If the hardware supports memory tagging, these tunables can be used to
+control the way @theglibc{} uses this feature.  Currently, only AArch64
+supports this feature.
+@end deftp
+
+@deftp Tunable glibc.memtag.enable
+This tunable takes a value between 0 and 255 and acts as a bitmask
+that enables various capabilities.
+
+Bit 0 (the least significant bit) causes the malloc subsystem to allocate
+tagged memory, with each allocation being assigned a random tag.
+
+Bit 1 enables precise faulting mode for tag violations on systems that
+support deferred tag violation reporting.  This may cause programs
+to run more slowly.
+
+Other bits are currently reserved.
+
+@Theglibc{} startup code will automatically enable memory tagging
+support in the kernel if this tunable has any non-zero value.
+
+The default value is @samp{0}, which disables all memory tagging.
+@end deftp