diff --git a/module/icp/algs/sha2/sha512_impl.c b/module/icp/algs/sha2/sha512_impl.c
index a85a71a83..4206f8f20 100644
--- a/module/icp/algs/sha2/sha512_impl.c
+++ b/module/icp/algs/sha2/sha512_impl.c
@@ -22,6 +22,7 @@
 
 /*
  * Copyright (c) 2022 Tino Reichardt <milky-zfs@mcmilk.de>
+ * Copyright (c) 2026, TrueNAS.
  */
 
 #include <sys/simd.h>
@@ -92,6 +93,20 @@ const sha512_ops_t sha512_avx2_impl = {
 };
 #endif
 
+#if defined(HAVE_SHA512EXT)
+static boolean_t sha2_have_sha512ext(void)
+{
+	return (kfpu_allowed() && zfs_sha512ext_available());
+}
+
+TF(zfs_sha512_transform_sha512ext, tf_sha512_sha512ext);
+const sha512_ops_t sha512_sha512ext_impl = {
+	.is_supported = sha2_have_sha512ext,
+	.transform = tf_sha512_sha512ext,
+	.name = "sha512ext"
+};
+#endif
+
 #elif defined(__aarch64__) || defined(__arm__)
 extern void zfs_sha512_block_armv7(uint64_t s[8], const void *, size_t);
 const sha512_ops_t sha512_armv7_impl = {
@@ -164,6 +179,9 @@ static const sha512_ops_t *const sha512_impls[] = {
 #if defined(__x86_64) && defined(HAVE_AVX2)
 	&sha512_avx2_impl,
 #endif
+#if defined(__x86_64) && defined(HAVE_SHA512EXT)
+	&sha512_sha512ext_impl,
+#endif
 #if defined(__aarch64__) || defined(__arm__)
 	&sha512_armv7_impl,
 #if defined(__aarch64__)
diff --git a/module/icp/asm-x86_64/sha2/sha512-x86_64.S b/module/icp/asm-x86_64/sha2/sha512-x86_64.S
index 9ed50ddc7..47e4edd51 100644
--- a/module/icp/asm-x86_64/sha2/sha512-x86_64.S
+++ b/module/icp/asm-x86_64/sha2/sha512-x86_64.S
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: Apache-2.0
 /*
- * Copyright 2004-2022 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 2004-2025 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -114,6 +114,50 @@ K512:
 .quad	0x0001020304050607,0x08090a0b0c0d0e0f
 .quad	0x0001020304050607,0x08090a0b0c0d0e0f
 
+.balign	64
+SET_OBJ(K512_single)
+K512_single:
+.quad	0x428a2f98d728ae22, 0x7137449123ef65cd
+.quad	0xb5c0fbcfec4d3b2f, 0xe9b5dba58189dbbc
+.quad	0x3956c25bf348b538, 0x59f111f1b605d019
+.quad	0x923f82a4af194f9b, 0xab1c5ed5da6d8118
+.quad	0xd807aa98a3030242, 0x12835b0145706fbe
+.quad	0x243185be4ee4b28c, 0x550c7dc3d5ffb4e2
+.quad	0x72be5d74f27b896f, 0x80deb1fe3b1696b1
+.quad	0x9bdc06a725c71235, 0xc19bf174cf692694
+.quad	0xe49b69c19ef14ad2, 0xefbe4786384f25e3
+.quad	0x0fc19dc68b8cd5b5, 0x240ca1cc77ac9c65
+.quad	0x2de92c6f592b0275, 0x4a7484aa6ea6e483
+.quad	0x5cb0a9dcbd41fbd4, 0x76f988da831153b5
+.quad	0x983e5152ee66dfab, 0xa831c66d2db43210
+.quad	0xb00327c898fb213f, 0xbf597fc7beef0ee4
+.quad	0xc6e00bf33da88fc2, 0xd5a79147930aa725
+.quad	0x06ca6351e003826f, 0x142929670a0e6e70
+.quad	0x27b70a8546d22ffc, 0x2e1b21385c26c926
+.quad	0x4d2c6dfc5ac42aed, 0x53380d139d95b3df
+.quad	0x650a73548baf63de, 0x766a0abb3c77b2a8
+.quad	0x81c2c92e47edaee6, 0x92722c851482353b
+.quad	0xa2bfe8a14cf10364, 0xa81a664bbc423001
+.quad	0xc24b8b70d0f89791, 0xc76c51a30654be30
+.quad	0xd192e819d6ef5218, 0xd69906245565a910
+.quad	0xf40e35855771202a, 0x106aa07032bbd1b8
+.quad	0x19a4c116b8d2d0c8, 0x1e376c085141ab53
+.quad	0x2748774cdf8eeb99, 0x34b0bcb5e19b48a8
+.quad	0x391c0cb3c5c95a63, 0x4ed8aa4ae3418acb
+.quad	0x5b9cca4f7763e373, 0x682e6ff3d6b2b8a3
+.quad	0x748f82ee5defb2fc, 0x78a5636f43172f60
+.quad	0x84c87814a1f0ab72, 0x8cc702081a6439ec
+.quad	0x90befffa23631e28, 0xa4506cebde82bde9
+.quad	0xbef9a3f7b2c67915, 0xc67178f2e372532b
+.quad	0xca273eceea26619c, 0xd186b8c721c0c207
+.quad	0xeada7dd6cde0eb1e, 0xf57d4f7fee6ed178
+.quad	0x06f067aa72176fba, 0x0a637dc5a2c898a6
+.quad	0x113f9804bef90dae, 0x1b710b35131c471b
+.quad	0x28db77f523047d84, 0x32caab7b40c72493
+.quad	0x3c9ebe0a15c9bebc, 0x431d67c49c100d4c
+.quad	0x4cc5d4becb3e42b6, 0x597f299cfc657e2a
+.quad	0x5fcb6fab3ad6faec, 0x6c44198c4a475817
+
 ENTRY_ALIGN(zfs_sha512_transform_x64, 16)
 .cfi_startproc
 	ENDBR
@@ -4010,6 +4054,278 @@ ENTRY_ALIGN(zfs_sha512_transform_avx2, 64)
 SET_SIZE(zfs_sha512_transform_avx2)
 STACK_FRAME_NON_STANDARD zfs_sha512_transform_avx2
 
+#ifdef HAVE_SHA512EXT
+ENTRY_ALIGN(zfs_sha512_transform_sha512ext, 64)
+.cfi_startproc	
+	ENDBR
+	orq	%rdx,%rdx
+	je	.Lsha512ext_done
+
+	vbroadcasti128	1280+K512(%rip),%ymm15
+
+
+
+
+
+
+
+
+
+
+	vmovdqu	0(%rdi),%ymm0
+	vmovdqu	32(%rdi),%ymm1
+
+	vperm2i128	$0x20,%ymm1,%ymm0,%ymm2
+	vperm2i128	$0x31,%ymm1,%ymm0,%ymm3
+
+	vpermq	$0x1b,%ymm2,%ymm13
+	vpermq	$0x1b,%ymm3,%ymm14
+
+
+	leaq	K512_single(%rip),%r9
+
+.balign	32
+.Lsha512ext_block_loop:
+
+	vmovdqa	%ymm13,%ymm11
+	vmovdqa	%ymm14,%ymm12
+
+
+	vmovdqu	0(%rsi),%ymm0
+	vpshufb	%ymm15,%ymm0,%ymm3
+	vpaddq	0(%r9),%ymm3,%ymm0
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+
+
+	vmovdqu	32(%rsi),%ymm0
+	vpshufb	%ymm15,%ymm0,%ymm4
+	vpaddq	32(%r9),%ymm4,%ymm0
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xdc
+
+
+	vmovdqu	64(%rsi),%ymm0
+	vpshufb	%ymm15,%ymm0,%ymm5
+	vpaddq	64(%r9),%ymm5,%ymm0
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xe5
+
+
+	vmovdqu	96(%rsi),%ymm0
+	vpshufb	%ymm15,%ymm0,%ymm6
+	vpaddq	96(%r9),%ymm6,%ymm0
+	vpermq	$0x1b,%ymm6,%ymm8
+	vpermq	$0x39,%ymm5,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm8
+	vpaddq	%ymm8,%ymm3,%ymm3
+.byte	0xc4,0xe2,0x7f,0xcd,0xde
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xee
+
+	vpaddq	128(%r9),%ymm3,%ymm0
+	vpermq	$0x1b,%ymm3,%ymm8
+	vpermq	$0x39,%ymm6,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm4,%ymm4
+.byte	0xc4,0xe2,0x7f,0xcd,0xe3
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xf3
+
+	vpaddq	160(%r9),%ymm4,%ymm0
+	vpermq	$0x1b,%ymm4,%ymm8
+	vpermq	$0x39,%ymm3,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm5,%ymm5
+.byte	0xc4,0xe2,0x7f,0xcd,0xec
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xdc
+
+	vpaddq	192(%r9),%ymm5,%ymm0
+	vpermq	$0x1b,%ymm5,%ymm8
+	vpermq	$0x39,%ymm4,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm6,%ymm6
+.byte	0xc4,0xe2,0x7f,0xcd,0xf5
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xe5
+
+	vpaddq	224(%r9),%ymm6,%ymm0
+	vpermq	$0x1b,%ymm6,%ymm8
+	vpermq	$0x39,%ymm5,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm3,%ymm3
+.byte	0xc4,0xe2,0x7f,0xcd,0xde
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xee
+
+	vpaddq	256(%r9),%ymm3,%ymm0
+	vpermq	$0x1b,%ymm3,%ymm8
+	vpermq	$0x39,%ymm6,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm4,%ymm4
+.byte	0xc4,0xe2,0x7f,0xcd,0xe3
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xf3
+
+	vpaddq	288(%r9),%ymm4,%ymm0
+	vpermq	$0x1b,%ymm4,%ymm8
+	vpermq	$0x39,%ymm3,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm5,%ymm5
+.byte	0xc4,0xe2,0x7f,0xcd,0xec
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xdc
+
+	vpaddq	320(%r9),%ymm5,%ymm0
+	vpermq	$0x1b,%ymm5,%ymm8
+	vpermq	$0x39,%ymm4,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm6,%ymm6
+.byte	0xc4,0xe2,0x7f,0xcd,0xf5
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xe5
+
+	vpaddq	352(%r9),%ymm6,%ymm0
+	vpermq	$0x1b,%ymm6,%ymm8
+	vpermq	$0x39,%ymm5,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm3,%ymm3
+.byte	0xc4,0xe2,0x7f,0xcd,0xde
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xee
+
+	vpaddq	384(%r9),%ymm3,%ymm0
+	vpermq	$0x1b,%ymm3,%ymm8
+	vpermq	$0x39,%ymm6,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm4,%ymm4
+.byte	0xc4,0xe2,0x7f,0xcd,0xe3
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xf3
+
+	vpaddq	416(%r9),%ymm4,%ymm0
+	vpermq	$0x1b,%ymm4,%ymm8
+	vpermq	$0x39,%ymm3,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm5,%ymm5
+.byte	0xc4,0xe2,0x7f,0xcd,0xec
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xdc
+
+	vpaddq	448(%r9),%ymm5,%ymm0
+	vpermq	$0x1b,%ymm5,%ymm8
+	vpermq	$0x39,%ymm4,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm6,%ymm6
+.byte	0xc4,0xe2,0x7f,0xcd,0xf5
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xe5
+
+	vpaddq	480(%r9),%ymm6,%ymm0
+	vpermq	$0x1b,%ymm6,%ymm8
+	vpermq	$0x39,%ymm5,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm3,%ymm3
+.byte	0xc4,0xe2,0x7f,0xcd,0xde
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xee
+
+	vpaddq	512(%r9),%ymm3,%ymm0
+	vpermq	$0x1b,%ymm3,%ymm8
+	vpermq	$0x39,%ymm6,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm4,%ymm4
+.byte	0xc4,0xe2,0x7f,0xcd,0xe3
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+.byte	0xc4,0xe2,0x7f,0xcc,0xf3
+
+
+	vpaddq	544(%r9),%ymm4,%ymm0
+	vpermq	$0x1b,%ymm4,%ymm8
+	vpermq	$0x39,%ymm3,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm5,%ymm5
+.byte	0xc4,0xe2,0x7f,0xcd,0xec
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+
+
+	vpaddq	576(%r9),%ymm5,%ymm0
+	vpermq	$0x1b,%ymm5,%ymm8
+	vpermq	$0x39,%ymm4,%ymm9
+	vpblendd	$0x3f,%ymm9,%ymm8,%ymm7
+	vpaddq	%ymm7,%ymm6,%ymm6
+.byte	0xc4,0xe2,0x7f,0xcd,0xf5
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+
+
+	vpaddq	608(%r9),%ymm6,%ymm0
+.byte	0xc4,0x62,0x27,0xcb,0xe0
+	vperm2i128	$0x1,%ymm0,%ymm0,%ymm0
+.byte	0xc4,0x62,0x1f,0xcb,0xd8
+
+
+	vpaddq	%ymm12,%ymm14,%ymm14
+	vpaddq	%ymm11,%ymm13,%ymm13
+	addq	$128,%rsi
+	decq	%rdx
+	jnz	.Lsha512ext_block_loop
+
+
+
+
+	vperm2i128	$0x31,%ymm14,%ymm13,%ymm1
+	vperm2i128	$0x20,%ymm14,%ymm13,%ymm2
+	vpermq	$0xb1,%ymm1,%ymm1
+	vpermq	$0xb1,%ymm2,%ymm2
+	vmovdqu	%ymm1,0(%rdi)
+	vmovdqu	%ymm2,32(%rdi)
+
+	vzeroupper
+.Lsha512ext_done:
+	RET
+.cfi_endproc
+SET_SIZE(zfs_sha512_transform_sha512ext)
+STACK_FRAME_NON_STANDARD zfs_sha512_transform_sha512ext
+#endif /* HAVE_SHA512EXT */
+
 /* Workaround for missing asm macro in RHEL 8. */
 #if defined(__linux__) && defined(HAVE_STACK_FRAME_NON_STANDARD) && \
     ! defined(HAVE_STACK_FRAME_NON_STANDARD_ASM)
@@ -4017,6 +4333,9 @@ STACK_FRAME_NON_STANDARD zfs_sha512_transform_avx2
 	.long zfs_sha512_transform_x64 - .
 	.long zfs_sha512_transform_avx - .
 	.long zfs_sha512_transform_avx2 - .
+#ifdef HAVE_SHA512EXT
+	.long zfs_sha512_transform_sha512ext - .
+#endif
 #endif
 
 #if defined(__ELF__)