diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index c66101ea32b8d..7b9a7a90e9e25 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -2124,6 +2124,186 @@ static int test_skcipher_vec(const char *driver, int enc,
 	return 0;
 }
 
+#ifdef CONFIG_CRYPTO_MANAGER_EXTRA_TESTS
+/*
+ * Generate a symmetric cipher test vector from the given implementation.
+ * Assumes the buffers in 'vec' were already allocated.
+ */
+static void generate_random_cipher_testvec(struct skcipher_request *req,
+					   struct cipher_testvec *vec,
+					   unsigned int maxdatasize,
+					   char *name, size_t max_namelen)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	const unsigned int maxkeysize = tfm->keysize;
+	const unsigned int ivsize = crypto_skcipher_ivsize(tfm);
+	struct scatterlist src, dst;
+	u8 iv[MAX_IVLEN];
+	DECLARE_CRYPTO_WAIT(wait);
+
+	/* Key: length in [0, maxkeysize], but usually choose maxkeysize */
+	vec->klen = maxkeysize;
+	if (prandom_u32() % 4 == 0)
+		vec->klen = prandom_u32() % (maxkeysize + 1);
+	generate_random_bytes((u8 *)vec->key, vec->klen);
+	vec->setkey_error = crypto_skcipher_setkey(tfm, vec->key, vec->klen);
+
+	/* IV */
+	generate_random_bytes((u8 *)vec->iv, ivsize);
+
+	/* Plaintext */
+	vec->len = generate_random_length(maxdatasize);
+	generate_random_bytes((u8 *)vec->ptext, vec->len);
+
+	/* If the key couldn't be set, no need to continue to encrypt. */
+	if (vec->setkey_error)
+		goto done;
+
+	/* Ciphertext */
+	sg_init_one(&src, vec->ptext, vec->len);
+	sg_init_one(&dst, vec->ctext, vec->len);
+	memcpy(iv, vec->iv, ivsize);
+	skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
+	skcipher_request_set_crypt(req, &src, &dst, vec->len, iv);
+	vec->crypt_error = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
+done:
+	snprintf(name, max_namelen, "\"random: len=%u klen=%u\"",
+		 vec->len, vec->klen);
+}
+
+/*
+ * Test the skcipher algorithm represented by @req against the corresponding
+ * generic implementation, if one is available.
+ */
+static int test_skcipher_vs_generic_impl(const char *driver,
+					 const char *generic_driver,
+					 struct skcipher_request *req,
+					 struct cipher_test_sglists *tsgls)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	const unsigned int ivsize = crypto_skcipher_ivsize(tfm);
+	const unsigned int blocksize = crypto_skcipher_blocksize(tfm);
+	const unsigned int maxdatasize = (2 * PAGE_SIZE) - TESTMGR_POISON_LEN;
+	const char *algname = crypto_skcipher_alg(tfm)->base.cra_name;
+	char _generic_driver[CRYPTO_MAX_ALG_NAME];
+	struct crypto_skcipher *generic_tfm = NULL;
+	struct skcipher_request *generic_req = NULL;
+	unsigned int i;
+	struct cipher_testvec vec = { 0 };
+	char vec_name[64];
+	struct testvec_config cfg;
+	char cfgname[TESTVEC_CONFIG_NAMELEN];
+	int err;
+
+	if (noextratests)
+		return 0;
+
+	/* Keywrap isn't supported here yet as it handles its IV differently. */
+	if (strncmp(algname, "kw(", 3) == 0)
+		return 0;
+
+	if (!generic_driver) { /* Use default naming convention? */
+		err = build_generic_driver_name(algname, _generic_driver);
+		if (err)
+			return err;
+		generic_driver = _generic_driver;
+	}
+
+	if (strcmp(generic_driver, driver) == 0) /* Already the generic impl? */
+		return 0;
+
+	generic_tfm = crypto_alloc_skcipher(generic_driver, 0, 0);
+	if (IS_ERR(generic_tfm)) {
+		err = PTR_ERR(generic_tfm);
+		if (err == -ENOENT) {
+			pr_warn("alg: skcipher: skipping comparison tests for %s because %s is unavailable\n",
+				driver, generic_driver);
+			return 0;
+		}
+		pr_err("alg: skcipher: error allocating %s (generic impl of %s): %d\n",
+		       generic_driver, algname, err);
+		return err;
+	}
+
+	generic_req = skcipher_request_alloc(generic_tfm, GFP_KERNEL);
+	if (!generic_req) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	/* Check the algorithm properties for consistency. */
+
+	if (tfm->keysize != generic_tfm->keysize) {
+		pr_err("alg: skcipher: max keysize for %s (%u) doesn't match generic impl (%u)\n",
+		       driver, tfm->keysize, generic_tfm->keysize);
+		err = -EINVAL;
+		goto out;
+	}
+
+	if (ivsize != crypto_skcipher_ivsize(generic_tfm)) {
+		pr_err("alg: skcipher: ivsize for %s (%u) doesn't match generic impl (%u)\n",
+		       driver, ivsize, crypto_skcipher_ivsize(generic_tfm));
+		err = -EINVAL;
+		goto out;
+	}
+
+	if (blocksize != crypto_skcipher_blocksize(generic_tfm)) {
+		pr_err("alg: skcipher: blocksize for %s (%u) doesn't match generic impl (%u)\n",
+		       driver, blocksize,
+		       crypto_skcipher_blocksize(generic_tfm));
+		err = -EINVAL;
+		goto out;
+	}
+
+	/*
+	 * Now generate test vectors using the generic implementation, and test
+	 * the other implementation against them.
+	 */
+
+	vec.key = kmalloc(tfm->keysize, GFP_KERNEL);
+	vec.iv = kmalloc(ivsize, GFP_KERNEL);
+	vec.ptext = kmalloc(maxdatasize, GFP_KERNEL);
+	vec.ctext = kmalloc(maxdatasize, GFP_KERNEL);
+	if (!vec.key || !vec.iv || !vec.ptext || !vec.ctext) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	for (i = 0; i < fuzz_iterations * 8; i++) {
+		generate_random_cipher_testvec(generic_req, &vec, maxdatasize,
+					       vec_name, sizeof(vec_name));
+		generate_random_testvec_config(&cfg, cfgname, sizeof(cfgname));
+
+		err = test_skcipher_vec_cfg(driver, ENCRYPT, &vec, vec_name,
+					    &cfg, req, tsgls);
+		if (err)
+			goto out;
+		err = test_skcipher_vec_cfg(driver, DECRYPT, &vec, vec_name,
+					    &cfg, req, tsgls);
+		if (err)
+			goto out;
+		cond_resched();
+	}
+	err = 0;
+out:
+	kfree(vec.key);
+	kfree(vec.iv);
+	kfree(vec.ptext);
+	kfree(vec.ctext);
+	crypto_free_skcipher(generic_tfm);
+	skcipher_request_free(generic_req);
+	return err;
+}
+#else /* !CONFIG_CRYPTO_MANAGER_EXTRA_TESTS */
+static int test_skcipher_vs_generic_impl(const char *driver,
+					 const char *generic_driver,
+					 struct skcipher_request *req,
+					 struct cipher_test_sglists *tsgls)
+{
+	return 0;
+}
+#endif /* !CONFIG_CRYPTO_MANAGER_EXTRA_TESTS */
+
 static int test_skcipher(const char *driver, int enc,
 			 const struct cipher_test_suite *suite,
 			 struct skcipher_request *req,
@@ -2183,6 +2363,11 @@ static int alg_test_skcipher(const struct alg_test_desc *desc,
 		goto out;
 
 	err = test_skcipher(driver, DECRYPT, suite, req, tsgls);
+	if (err)
+		goto out;
+
+	err = test_skcipher_vs_generic_impl(driver, desc->generic_driver, req,
+					    tsgls);
 out:
 	free_cipher_test_sglists(tsgls);
 	skcipher_request_free(req);
@@ -3138,12 +3323,14 @@ static int alg_test_null(const struct alg_test_desc *desc,
 static const struct alg_test_desc alg_test_descs[] = {
 	{
 		.alg = "adiantum(xchacha12,aes)",
+		.generic_driver = "adiantum(xchacha12-generic,aes-generic,nhpoly1305-generic)",
 		.test = alg_test_skcipher,
 		.suite = {
 			.cipher = __VECS(adiantum_xchacha12_aes_tv_template)
 		},
 	}, {
 		.alg = "adiantum(xchacha20,aes)",
+		.generic_driver = "adiantum(xchacha20-generic,aes-generic,nhpoly1305-generic)",
 		.test = alg_test_skcipher,
 		.suite = {
 			.cipher = __VECS(adiantum_xchacha20_aes_tv_template)
@@ -3916,30 +4103,35 @@ static const struct alg_test_desc alg_test_descs[] = {
 		}
 	}, {
 		.alg = "lrw(aes)",
+		.generic_driver = "lrw(ecb(aes-generic))",
 		.test = alg_test_skcipher,
 		.suite = {
 			.cipher = __VECS(aes_lrw_tv_template)
 		}
 	}, {
 		.alg = "lrw(camellia)",
+		.generic_driver = "lrw(ecb(camellia-generic))",
 		.test = alg_test_skcipher,
 		.suite = {
 			.cipher = __VECS(camellia_lrw_tv_template)
 		}
 	}, {
 		.alg = "lrw(cast6)",
+		.generic_driver = "lrw(ecb(cast6-generic))",
 		.test = alg_test_skcipher,
 		.suite = {
 			.cipher = __VECS(cast6_lrw_tv_template)
 		}
 	}, {
 		.alg = "lrw(serpent)",
+		.generic_driver = "lrw(ecb(serpent-generic))",
 		.test = alg_test_skcipher,
 		.suite = {
 			.cipher = __VECS(serpent_lrw_tv_template)
 		}
 	}, {
 		.alg = "lrw(twofish)",
+		.generic_driver = "lrw(ecb(twofish-generic))",
 		.test = alg_test_skcipher,
 		.suite = {
 			.cipher = __VECS(tf_lrw_tv_template)
@@ -4274,6 +4466,7 @@ static const struct alg_test_desc alg_test_descs[] = {
 		},
 	}, {
 		.alg = "xts(aes)",
+		.generic_driver = "xts(ecb(aes-generic))",
 		.test = alg_test_skcipher,
 		.fips_allowed = 1,
 		.suite = {
@@ -4281,12 +4474,14 @@ static const struct alg_test_desc alg_test_descs[] = {
 		}
 	}, {
 		.alg = "xts(camellia)",
+		.generic_driver = "xts(ecb(camellia-generic))",
 		.test = alg_test_skcipher,
 		.suite = {
 			.cipher = __VECS(camellia_xts_tv_template)
 		}
 	}, {
 		.alg = "xts(cast6)",
+		.generic_driver = "xts(ecb(cast6-generic))",
 		.test = alg_test_skcipher,
 		.suite = {
 			.cipher = __VECS(cast6_xts_tv_template)
@@ -4300,12 +4495,14 @@ static const struct alg_test_desc alg_test_descs[] = {
 		.fips_allowed = 1,
 	}, {
 		.alg = "xts(serpent)",
+		.generic_driver = "xts(ecb(serpent-generic))",
 		.test = alg_test_skcipher,
 		.suite = {
 			.cipher = __VECS(serpent_xts_tv_template)
 		}
 	}, {
 		.alg = "xts(twofish)",
+		.generic_driver = "xts(ecb(twofish-generic))",
 		.test = alg_test_skcipher,
 		.suite = {
 			.cipher = __VECS(tf_xts_tv_template)
diff --git a/crypto/testmgr.h b/crypto/testmgr.h
index beb9bd79fe1fa..e03f4f72723b1 100644
--- a/crypto/testmgr.h
+++ b/crypto/testmgr.h
@@ -71,7 +71,7 @@ struct cipher_testvec {
 	const char *ptext;
 	const char *ctext;
 	unsigned char wk; /* weak key flag */
-	unsigned char klen;
+	unsigned short klen;
 	unsigned short len;
 	bool fips_skip;
 	bool generates_iv;
