The Morello Pure Capability kernel uABI defines new a_type entries:
https://git.morello-project.org/morello/kernel/linux/-/wikis/Morello-pure-capability-kernel-user-Linux-ABI-specification#auxiliary-vector-auxv
#define AT_MINSIGSTKSZ 51 /* Stack needed for signal delivery */
+# define AT_CHERI_EXEC_RW_CAP 60
+# define AT_CHERI_EXEC_RX_CAP 61
+# define AT_CHERI_INTERP_RW_CAP 62
+# define AT_CHERI_INTERP_RX_CAP 63
+# define AT_CHERI_SEAL_CAP 64
+
/* Note section contents. Each entry in the note section begins with
a header of a fixed form. */