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diff --git a/Documentation/arm64/sve.txt b/Documentation/arm64/sve.txt
index 7169a0ec41d8..9940e924a47e 100644
--- a/Documentation/arm64/sve.txt
+++ b/Documentation/arm64/sve.txt
@@ -34,6 +34,23 @@ model features for SVE is included in Appendix A.
following sections: software that needs to verify that those interfaces are
present must check for HWCAP_SVE instead.
+* On hardware that supports the SVE2 extensions, HWCAP2_SVE2 will also
+ be reported in the AT_HWCAP2 aux vector entry. In addition to this,
+ optional extensions to SVE2 may be reported by the presence of:
+
+ HWCAP2_SVE2
+ HWCAP2_SVEAES
+ HWCAP2_SVEPMULL
+ HWCAP2_SVEBITPERM
+ HWCAP2_SVESHA3
+ HWCAP2_SVESM4
+
+ This list may be extended over time as the SVE architecture evolves.
+
+ These extensions are also reported via the CPU ID register ID_AA64ZFR0_EL1,
+ which userspace can read using an MRS instruction. See elf_hwcaps.txt and
+ cpu-feature-registers.txt for details.
+
* Debuggers should restrict themselves to interacting with the target via the
NT_ARM_SVE regset. The recommended way of detecting support for this regset
is to connect to a target process first and then attempt a