diff --git a/sys/arm/include/elf.h b/sys/arm/include/elf.h
index 8b498b69caba..4dc0d456892b 100644
--- a/sys/arm/include/elf.h
+++ b/sys/arm/include/elf.h
@@ -85,8 +85,9 @@ __ElfType(Auxinfo);
 #define	AT_TIMEKEEP	22	/* Pointer to timehands. */
 #define	AT_STACKPROT	23	/* Initial stack protection. */
 #define	AT_EHDRFLAGS	24	/* e_flags field from elf hdr */
+#define	AT_HWCAP	25	/* CPU feature flags. */
 
-#define	AT_COUNT	25	/* Count of defined aux entry types. */
+#define	AT_COUNT	26	/* Count of defined aux entry types. */
 
 #define	R_ARM_COUNT	33	/* Count of defined relocation types. */
 
diff --git a/sys/arm64/include/elf.h b/sys/arm64/include/elf.h
index 32f2e64d9ae1..33041efcda52 100644
--- a/sys/arm64/include/elf.h
+++ b/sys/arm64/include/elf.h
@@ -90,8 +90,10 @@ __ElfType(Auxinfo);
 #define	AT_PAGESIZESLEN	21	/* Number of pagesizes. */
 #define	AT_TIMEKEEP	22	/* Pointer to timehands. */
 #define	AT_STACKPROT	23	/* Initial stack protection. */
+#define	AT_EHDRFLAGS	24	/* e_flags field from elf hdr */
+#define	AT_HWCAP	25	/* CPU feature flags. */
 
-#define	AT_COUNT	24	/* Count of defined aux entry types. */
+#define	AT_COUNT	26	/* Count of defined aux entry types. */
 
 /* Define "machine" characteristics */
 #define	ELF_TARG_CLASS	ELFCLASS64
diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c
index c3695da3b0e2..57ea9112ef4b 100644
--- a/sys/kern/imgact_elf.c
+++ b/sys/kern/imgact_elf.c
@@ -1110,9 +1110,7 @@ __elfN(freebsd_fixup)(register_t **stack_base, struct image_params *imgp)
 	AUXARGS_ENTRY(pos, AT_FLAGS, args->flags);
 	AUXARGS_ENTRY(pos, AT_ENTRY, args->entry);
 	AUXARGS_ENTRY(pos, AT_BASE, args->base);
-#ifdef AT_EHDRFLAGS
 	AUXARGS_ENTRY(pos, AT_EHDRFLAGS, args->hdr_eflags);
-#endif
 	if (imgp->execpathp != 0)
 		AUXARGS_ENTRY(pos, AT_EXECPATH, imgp->execpathp);
 	AUXARGS_ENTRY(pos, AT_OSRELDATE,
@@ -1133,6 +1131,8 @@ __elfN(freebsd_fixup)(register_t **stack_base, struct image_params *imgp)
 	AUXARGS_ENTRY(pos, AT_STACKPROT, imgp->sysent->sv_shared_page_obj
 	    != NULL && imgp->stack_prot != 0 ? imgp->stack_prot :
 	    imgp->sysent->sv_stackprot);
+	if (imgp->sysent->sv_hwcap != NULL)
+		AUXARGS_ENTRY(pos, AT_HWCAP, *imgp->sysent->sv_hwcap);
 	AUXARGS_ENTRY(pos, AT_NULL, 0);
 
 	free(imgp->auxargs, M_TEMP);
diff --git a/sys/mips/include/elf.h b/sys/mips/include/elf.h
index a33c09027e78..b6b699682abf 100644
--- a/sys/mips/include/elf.h
+++ b/sys/mips/include/elf.h
@@ -144,8 +144,10 @@ __ElfType(Auxinfo);
 #define	AT_PAGESIZESLEN	21	/* Number of pagesizes. */
 #define	AT_TIMEKEEP	22	/* Pointer to timehands. */
 #define	AT_STACKPROT	23	/* Initial stack protection. */
+#define	AT_EHDRFLAGS	24	/* e_flags field from elf hdr */
+#define	AT_HWCAP	25	/* CPU feature flags. */
 
-#define	AT_COUNT	24	/* Count of defined aux entry types. */
+#define	AT_COUNT	26	/* Count of defined aux entry types. */
 
 #define	ET_DYN_LOAD_ADDR 0x0120000
 
diff --git a/sys/powerpc/include/elf.h b/sys/powerpc/include/elf.h
index 0e81b4a7c9fd..28f8d7e5874f 100644
--- a/sys/powerpc/include/elf.h
+++ b/sys/powerpc/include/elf.h
@@ -107,8 +107,10 @@ __ElfType(Auxinfo);
 #define	AT_PAGESIZESLEN	19	/* Number of pagesizes. */
 #define	AT_STACKPROT	21	/* Initial stack protection. */
 #define	AT_TIMEKEEP	22	/* Pointer to timehands. */
+#define	AT_EHDRFLAGS	24	/* e_flags field from elf hdr */
+#define	AT_HWCAP	25	/* CPU feature flags. */
 
-#define	AT_COUNT	23	/* Count of defined aux entry types. */
+#define	AT_COUNT	26	/* Count of defined aux entry types. */
 
 /*
  * Relocation types.
diff --git a/sys/riscv/include/elf.h b/sys/riscv/include/elf.h
index 3a89577ebe31..1a0d067a2526 100644
--- a/sys/riscv/include/elf.h
+++ b/sys/riscv/include/elf.h
@@ -90,8 +90,10 @@ __ElfType(Auxinfo);
 #define	AT_PAGESIZESLEN	21	/* Number of pagesizes. */
 #define	AT_TIMEKEEP	22	/* Pointer to timehands. */
 #define	AT_STACKPROT	23	/* Initial stack protection. */
+#define	AT_EHDRFLAGS	24	/* e_flags field from elf hdr */
+#define	AT_HWCAP	25	/* CPU feature flags. */
 
-#define	AT_COUNT	24	/* Count of defined aux entry types. */
+#define	AT_COUNT	26	/* Count of defined aux entry types. */
 
 /* Define "machine" characteristics */
 #define	ELF_TARG_CLASS	ELFCLASS64
diff --git a/sys/sparc64/include/elf.h b/sys/sparc64/include/elf.h
index 448ca66793ec..22ee3cb46e75 100644
--- a/sys/sparc64/include/elf.h
+++ b/sys/sparc64/include/elf.h
@@ -92,8 +92,10 @@ __ElfType(Auxinfo);
 #define	AT_PAGESIZESLEN	21	/* Number of pagesizes. */
 #define	AT_TIMEKEEP	22	/* Pointer to timehands. */
 #define	AT_STACKPROT	23	/* Initial stack protection. */
+#define	AT_EHDRFLAGS	24	/* e_flags field from elf hdr */
+#define	AT_HWCAP	25	/* CPU feature flags. */
 
-#define	AT_COUNT	24	/* Count of defined aux entry types. */
+#define	AT_COUNT	26	/* Count of defined aux entry types. */
 
 /* Define "machine" characteristics */
 #if __ELF_WORD_SIZE == 32
diff --git a/sys/sys/sysent.h b/sys/sys/sysent.h
index a4049876454b..c03f9b4c9f7d 100644
--- a/sys/sys/sysent.h
+++ b/sys/sys/sysent.h
@@ -129,6 +129,7 @@ struct sysentvec {
 	void		(*sv_schedtail)(struct thread *);
 	void		(*sv_thread_detach)(struct thread *);
 	int		(*sv_trap)(struct thread *);
+	u_long		*sv_hwcap;	/* Value passed in AT_HWCAP. */
 };
 
 #define	SV_ILP32	0x000100	/* 32-bit executable. */
diff --git a/sys/x86/include/elf.h b/sys/x86/include/elf.h
index cde395b30bfe..e7df2b615076 100644
--- a/sys/x86/include/elf.h
+++ b/sys/x86/include/elf.h
@@ -100,8 +100,10 @@ __ElfType(Auxinfo);
 #define	AT_PAGESIZESLEN	21	/* Number of pagesizes. */
 #define	AT_TIMEKEEP	22	/* Pointer to timehands. */
 #define	AT_STACKPROT	23	/* Initial stack protection. */
+#define	AT_EHDRFLAGS	24	/* e_flags field from elf hdr */
+#define	AT_HWCAP	25	/* CPU feature flags. */
 
-#define	AT_COUNT	24	/* Count of defined aux entry types. */
+#define	AT_COUNT	26	/* Count of defined aux entry types. */
 
 /*
  * Relocation types.