[PATCH 0/7] selftests: vDSO: Some cleanups and fixes

[PATCH 0/7] selftests: vDSO: Some cleanups and fixes

[Thomas Weißschuh]

Fixes and cleanups for various issues in the vDSO selftests.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
Thomas Weißschuh (7):
      selftests: vDSO: chacha: Correctly skip test if necessary
      selftests: vDSO: clock_getres: Drop unused include of err.h
      selftests: vDSO: vdso_test_correctness: Fix -Wold-style-definitions
      selftests: vDSO: vdso_test_getrandom: Drop unused include of linux/compiler.h
      selftests: vDSO: vdso_test_getrandom: Drop some dead code
      selftests: vDSO: vdso_test_getrandom: Always print TAP header
      selftests: vDSO: vdso_config: Avoid -Wunused-variables

 tools/testing/selftests/vDSO/vdso_config.h            |  2 ++
 tools/testing/selftests/vDSO/vdso_test_chacha.c       |  3 ++-
 tools/testing/selftests/vDSO/vdso_test_clock_getres.c |  1 -
 tools/testing/selftests/vDSO/vdso_test_correctness.c  |  2 +-
 tools/testing/selftests/vDSO/vdso_test_getrandom.c    | 18 +++++-------------
 5 files changed, 10 insertions(+), 16 deletions(-)
---
base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8
change-id: 20250423-selftests-vdso-fixes-d2ce74142359

Best regards,
-- 
Thomas Weißschuh <thomas.weissschuh@linutronix.de>

[PATCH 1/7] selftests: vDSO: chacha: Correctly skip test if necessary

[Thomas Weißschuh]

According to kselftest.h ksft_exit_skip() is not meant to be called when
a plan has already been printed.

Use the recommended function ksft_test_result_skip().

This fixes a bug, where the TAP output would be invalid when skipping:

	TAP version 13
	1..1
	ok 2 # SKIP Not implemented on architecture

The SKIP line should start with "ok 1" as the plan only contains one test.

Fixes: 3b5992eaf730 ("selftests: vDSO: unconditionally build chacha test")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>

---
I'm not sure if this is not a general bug in ksft_exit_skip().
First ksft_xskip is incremented then read back through ksft_test_num() and
then that result is incremented again.

In any case, using the correct function is better.
---
 tools/testing/selftests/vDSO/vdso_test_chacha.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/vDSO/vdso_test_chacha.c b/tools/testing/selftests/vDSO/vdso_test_chacha.c
index 8757f738b0b1a76a48c83c5e5df79925a30c1bc7..0aad682b12c8836efabb49a65a47cf87466891a3 100644
--- a/tools/testing/selftests/vDSO/vdso_test_chacha.c
+++ b/tools/testing/selftests/vDSO/vdso_test_chacha.c
@@ -76,7 +76,8 @@ static void reference_chacha20_blocks(uint8_t *dst_bytes, const uint32_t *key, u
 
 void __weak __arch_chacha20_blocks_nostack(uint8_t *dst_bytes, const uint32_t *key, uint32_t *counter, size_t nblocks)
 {
-	ksft_exit_skip("Not implemented on architecture\n");
+	ksft_test_result_skip("Not implemented on architecture\n");
+	ksft_finished();
 }
 
 int main(int argc, char *argv[])

-- 
2.49.0

Re: [PATCH 1/7] selftests: vDSO: chacha: Correctly skip test if necessary

[Muhammad Usama Anjum]

On 5/2/25 5:40 PM, Thomas Weißschuh wrote:
> According to kselftest.h ksft_exit_skip() is not meant to be called when
> a plan has already been printed.
Agreed

> 
> Use the recommended function ksft_test_result_skip().
> 
> This fixes a bug, where the TAP output would be invalid when skipping:
> 
> 	TAP version 13
> 	1..1
> 	ok 2 # SKIP Not implemented on architecture
> 
> The SKIP line should start with "ok 1" as the plan only contains one test.
> 
> Fixes: 3b5992eaf730 ("selftests: vDSO: unconditionally build chacha test")
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>

> 
> ---
> I'm not sure if this is not a general bug in ksft_exit_skip().
> First ksft_xskip is incremented then read back through ksft_test_num() and
> then that result is incremented again.
> 
> In any case, using the correct function is better.
> ---
>  tools/testing/selftests/vDSO/vdso_test_chacha.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/vDSO/vdso_test_chacha.c b/tools/testing/selftests/vDSO/vdso_test_chacha.c
> index 8757f738b0b1a76a48c83c5e5df79925a30c1bc7..0aad682b12c8836efabb49a65a47cf87466891a3 100644
> --- a/tools/testing/selftests/vDSO/vdso_test_chacha.c
> +++ b/tools/testing/selftests/vDSO/vdso_test_chacha.c
> @@ -76,7 +76,8 @@ static void reference_chacha20_blocks(uint8_t *dst_bytes, const uint32_t *key, u
>  
>  void __weak __arch_chacha20_blocks_nostack(uint8_t *dst_bytes, const uint32_t *key, uint32_t *counter, size_t nblocks)
>  {
> -	ksft_exit_skip("Not implemented on architecture\n");
> +	ksft_test_result_skip("Not implemented on architecture\n");
> +	ksft_finished();
>  }
>  
>  int main(int argc, char *argv[])
> 


-- 
Regards,
Usama

[PATCH 2/7] selftests: vDSO: clock_getres: Drop unused include of err.h

[Thomas Weißschuh]

Nothing from err.h is used.

Drop the include.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
 tools/testing/selftests/vDSO/vdso_test_clock_getres.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/tools/testing/selftests/vDSO/vdso_test_clock_getres.c b/tools/testing/selftests/vDSO/vdso_test_clock_getres.c
index 38d46a8bf7cba7a9b4a9b13b5eb17aa207972bd0..b5d5f59f725a703c357dfca91bfe170aaaeb42fa 100644
--- a/tools/testing/selftests/vDSO/vdso_test_clock_getres.c
+++ b/tools/testing/selftests/vDSO/vdso_test_clock_getres.c
@@ -13,7 +13,6 @@
 
 #define _GNU_SOURCE
 #include <elf.h>
-#include <err.h>
 #include <fcntl.h>
 #include <stdint.h>
 #include <stdio.h>

-- 
2.49.0

Re: [PATCH 2/7] selftests: vDSO: clock_getres: Drop unused include of err.h

[Muhammad Usama Anjum]

On 5/2/25 5:40 PM, Thomas Weißschuh wrote:
> Nothing from err.h is used.
> 
> Drop the include.
> 
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>

> ---
>  tools/testing/selftests/vDSO/vdso_test_clock_getres.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/vDSO/vdso_test_clock_getres.c b/tools/testing/selftests/vDSO/vdso_test_clock_getres.c
> index 38d46a8bf7cba7a9b4a9b13b5eb17aa207972bd0..b5d5f59f725a703c357dfca91bfe170aaaeb42fa 100644
> --- a/tools/testing/selftests/vDSO/vdso_test_clock_getres.c
> +++ b/tools/testing/selftests/vDSO/vdso_test_clock_getres.c
> @@ -13,7 +13,6 @@
>  
>  #define _GNU_SOURCE
>  #include <elf.h>
> -#include <err.h>
>  #include <fcntl.h>
>  #include <stdint.h>
>  #include <stdio.h>
> 


-- 
Regards,
Usama

[PATCH 3/7] selftests: vDSO: vdso_test_correctness: Fix -Wold-style-definitions

[Thomas Weißschuh]

Functions definitions without any argument list produce a warning with
-Wold-style-definition:

vdso_test_correctness.c:111:13: warning: old-style function definition [-Wold-style-definition]
  111 | static void fill_function_pointers()
      |             ^~~~~~~~~~~~~~~~~~~~~~

Explicitly use an empty argument list.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
 tools/testing/selftests/vDSO/vdso_test_correctness.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/vDSO/vdso_test_correctness.c b/tools/testing/selftests/vDSO/vdso_test_correctness.c
index 5fb97ad67eeaf17b6cfa4f82783c57894f03e5c5..da651cf53c6ca4242085de109c7fc57bd807297c 100644
--- a/tools/testing/selftests/vDSO/vdso_test_correctness.c
+++ b/tools/testing/selftests/vDSO/vdso_test_correctness.c
@@ -108,7 +108,7 @@ static void *vsyscall_getcpu(void)
 }
 
 
-static void fill_function_pointers()
+static void fill_function_pointers(void)
 {
 	void *vdso = dlopen("linux-vdso.so.1",
 			    RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);

-- 
2.49.0

Re: [PATCH 3/7] selftests: vDSO: vdso_test_correctness: Fix -Wold-style-definitions

[Muhammad Usama Anjum]

On 5/2/25 5:40 PM, Thomas Weißschuh wrote:
> Functions definitions without any argument list produce a warning with
> -Wold-style-definition:
> 
> vdso_test_correctness.c:111:13: warning: old-style function definition [-Wold-style-definition]
>   111 | static void fill_function_pointers()
>       |             ^~~~~~~~~~~~~~~~~~~~~~
This warning doesn't appear on my side. Are you using extra compiler
flags? If yes, please add them to the Makefile.

> 
> Explicitly use an empty argument list.
> 
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> ---
>  tools/testing/selftests/vDSO/vdso_test_correctness.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/vDSO/vdso_test_correctness.c b/tools/testing/selftests/vDSO/vdso_test_correctness.c
> index 5fb97ad67eeaf17b6cfa4f82783c57894f03e5c5..da651cf53c6ca4242085de109c7fc57bd807297c 100644
> --- a/tools/testing/selftests/vDSO/vdso_test_correctness.c
> +++ b/tools/testing/selftests/vDSO/vdso_test_correctness.c
> @@ -108,7 +108,7 @@ static void *vsyscall_getcpu(void)
>  }
>  
>  
> -static void fill_function_pointers()
> +static void fill_function_pointers(void)
>  {
>  	void *vdso = dlopen("linux-vdso.so.1",
>  			    RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
> 


-- 
Regards,
Usama

[PATCH 4/7] selftests: vDSO: vdso_test_getrandom: Drop unused include of linux/compiler.h

[Thomas Weißschuh]

The header is unused. Furthermore this is not a real UAPI header,
but only exists in tools/include/.
This prevents building the selftest against real UAPI headers.

Drop the include.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
 tools/testing/selftests/vDSO/vdso_test_getrandom.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/tools/testing/selftests/vDSO/vdso_test_getrandom.c b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
index 95057f7567db22226d9cb09a667a56e387a33a46..f36e50f372f935e6d4da3175c81e210653bdce1d 100644
--- a/tools/testing/selftests/vDSO/vdso_test_getrandom.c
+++ b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
@@ -21,7 +21,6 @@
 #include <sys/wait.h>
 #include <sys/types.h>
 #include <linux/random.h>
-#include <linux/compiler.h>
 #include <linux/ptrace.h>
 
 #include "../kselftest.h"

-- 
2.49.0

[PATCH 5/7] selftests: vDSO: vdso_test_getrandom: Drop some dead code

[Thomas Weißschuh]

vgetrandom_put_state() and the variable ret in kselftest() are never used.

Drop the dead code.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
 tools/testing/selftests/vDSO/vdso_test_getrandom.c | 11 +----------
 1 file changed, 1 insertion(+), 10 deletions(-)

diff --git a/tools/testing/selftests/vDSO/vdso_test_getrandom.c b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
index f36e50f372f935e6d4da3175c81e210653bdce1d..b0e0d664508a38d6dde9df0a61ec8198ee928a17 100644
--- a/tools/testing/selftests/vDSO/vdso_test_getrandom.c
+++ b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
@@ -100,15 +100,6 @@ static void *vgetrandom_get_state(void)
 	return state;
 }
 
-static void vgetrandom_put_state(void *state)
-{
-	if (!state)
-		return;
-	pthread_mutex_lock(&vgrnd.lock);
-	vgrnd.states[vgrnd.len++] = state;
-	pthread_mutex_unlock(&vgrnd.lock);
-}
-
 static void vgetrandom_init(void)
 {
 	const char *version = versions[VDSO_VERSION];
@@ -264,7 +255,7 @@ static void kselftest(void)
 	}
 	for (;;) {
 		struct ptrace_syscall_info info = { 0 };
-		int status, ret;
+		int status;
 		ksft_assert(waitpid(child, &status, 0) >= 0);
 		if (WIFEXITED(status)) {
 			ksft_assert(WEXITSTATUS(status) == 0);

-- 
2.49.0

Re: [PATCH 5/7] selftests: vDSO: vdso_test_getrandom: Drop some dead code

[Muhammad Usama Anjum]

On 5/2/25 5:40 PM, Thomas Weißschuh wrote:
> vgetrandom_put_state() and the variable ret in kselftest() are never used.
> 
> Drop the dead code.
> 
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>

> ---
>  tools/testing/selftests/vDSO/vdso_test_getrandom.c | 11 +----------
>  1 file changed, 1 insertion(+), 10 deletions(-)
> 
> diff --git a/tools/testing/selftests/vDSO/vdso_test_getrandom.c b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
> index f36e50f372f935e6d4da3175c81e210653bdce1d..b0e0d664508a38d6dde9df0a61ec8198ee928a17 100644
> --- a/tools/testing/selftests/vDSO/vdso_test_getrandom.c
> +++ b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
> @@ -100,15 +100,6 @@ static void *vgetrandom_get_state(void)
>  	return state;
>  }
>  
> -static void vgetrandom_put_state(void *state)
> -{
> -	if (!state)
> -		return;
> -	pthread_mutex_lock(&vgrnd.lock);
> -	vgrnd.states[vgrnd.len++] = state;
> -	pthread_mutex_unlock(&vgrnd.lock);
> -}
> -
>  static void vgetrandom_init(void)
>  {
>  	const char *version = versions[VDSO_VERSION];
> @@ -264,7 +255,7 @@ static void kselftest(void)
>  	}
>  	for (;;) {
>  		struct ptrace_syscall_info info = { 0 };
> -		int status, ret;
> +		int status;
>  		ksft_assert(waitpid(child, &status, 0) >= 0);
>  		if (WIFEXITED(status)) {
>  			ksft_assert(WEXITSTATUS(status) == 0);
> 


-- 
Regards,
Usama

[PATCH 6/7] selftests: vDSO: vdso_test_getrandom: Always print TAP header

[Thomas Weißschuh]

The TAP specification requires that the output begins with a header line.
If vgetrandom_init() fails and skips the test, that header line is missing.

Call vgetrandom_init() after ksft_print_header().

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
 tools/testing/selftests/vDSO/vdso_test_getrandom.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/vDSO/vdso_test_getrandom.c b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
index b0e0d664508a38d6dde9df0a61ec8198ee928a17..01892d8e65d754d0353f7df2b63910d5be8cd1bc 100644
--- a/tools/testing/selftests/vDSO/vdso_test_getrandom.c
+++ b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
@@ -232,6 +232,7 @@ static void kselftest(void)
 	pid_t child;
 
 	ksft_print_header();
+	vgetrandom_init();
 	ksft_set_plan(2);
 
 	for (size_t i = 0; i < 1000; ++i) {
@@ -285,8 +286,6 @@ static void usage(const char *argv0)
 
 int main(int argc, char *argv[])
 {
-	vgetrandom_init();
-
 	if (argc == 1) {
 		kselftest();
 		return 0;
@@ -296,6 +295,9 @@ int main(int argc, char *argv[])
 		usage(argv[0]);
 		return 1;
 	}
+
+	vgetrandom_init();
+
 	if (!strcmp(argv[1], "bench-single"))
 		bench_single();
 	else if (!strcmp(argv[1], "bench-multi"))

-- 
2.49.0

Re: [PATCH 6/7] selftests: vDSO: vdso_test_getrandom: Always print TAP header

[Muhammad Usama Anjum]

On 5/2/25 5:40 PM, Thomas Weißschuh wrote:
> The TAP specification requires that the output begins with a header line.
> If vgetrandom_init() fails and skips the test, that header line is missing.
> 
> Call vgetrandom_init() after ksft_print_header().
> 
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>

> ---
>  tools/testing/selftests/vDSO/vdso_test_getrandom.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/testing/selftests/vDSO/vdso_test_getrandom.c b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
> index b0e0d664508a38d6dde9df0a61ec8198ee928a17..01892d8e65d754d0353f7df2b63910d5be8cd1bc 100644
> --- a/tools/testing/selftests/vDSO/vdso_test_getrandom.c
> +++ b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
> @@ -232,6 +232,7 @@ static void kselftest(void)
>  	pid_t child;
>  
>  	ksft_print_header();
> +	vgetrandom_init();
>  	ksft_set_plan(2);
>  
>  	for (size_t i = 0; i < 1000; ++i) {
> @@ -285,8 +286,6 @@ static void usage(const char *argv0)
>  
>  int main(int argc, char *argv[])
>  {
> -	vgetrandom_init();
> -
>  	if (argc == 1) {
>  		kselftest();
>  		return 0;
> @@ -296,6 +295,9 @@ int main(int argc, char *argv[])
>  		usage(argv[0]);
>  		return 1;
>  	}
> +
> +	vgetrandom_init();
> +
>  	if (!strcmp(argv[1], "bench-single"))
>  		bench_single();
>  	else if (!strcmp(argv[1], "bench-multi"))
> 


-- 
Regards,
Usama

[PATCH 7/7] selftests: vDSO: vdso_config: Avoid -Wunused-variables

[Thomas Weißschuh]

Not all users of this header make use of all its variables.
For example vdso_test_correctness.c does not use "versions":

In file included from vdso_test_correctness.c:22:
vdso_config.h:61:20: warning: ‘versions’ defined but not used [-Wunused-variable]
   61 | static const char *versions[7] = {
      |                    ^~~~~~~~

Avoid those warnings through attribute((unused)).

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
 tools/testing/selftests/vDSO/vdso_config.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/testing/selftests/vDSO/vdso_config.h b/tools/testing/selftests/vDSO/vdso_config.h
index 722260f9756198956f0dfccced907284b6851e76..5fdd0f36233742bc47ae79f23d2cfae5a0f56dee 100644
--- a/tools/testing/selftests/vDSO/vdso_config.h
+++ b/tools/testing/selftests/vDSO/vdso_config.h
@@ -58,6 +58,7 @@
 #define VDSO_NAMES		1
 #endif
 
+__attribute__((unused))
 static const char *versions[7] = {
 	"LINUX_2.6",
 	"LINUX_2.6.15",
@@ -68,6 +69,7 @@ static const char *versions[7] = {
 	"LINUX_5.10"
 };
 
+__attribute__((unused))
 static const char *names[2][7] = {
 	{
 		"__kernel_gettimeofday",

-- 
2.49.0

Re: [PATCH 7/7] selftests: vDSO: vdso_config: Avoid -Wunused-variables

[Muhammad Usama Anjum]

On 5/2/25 5:40 PM, Thomas Weißschuh wrote:
> Not all users of this header make use of all its variables.
> For example vdso_test_correctness.c does not use "versions":
> 
> In file included from vdso_test_correctness.c:22:
> vdso_config.h:61:20: warning: ‘versions’ defined but not used [-Wunused-variable]
>    61 | static const char *versions[7] = {
>       |                    ^~~~~~~~
> 
> Avoid those warnings through attribute((unused)).
> 
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>

> ---
>  tools/testing/selftests/vDSO/vdso_config.h | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/tools/testing/selftests/vDSO/vdso_config.h b/tools/testing/selftests/vDSO/vdso_config.h
> index 722260f9756198956f0dfccced907284b6851e76..5fdd0f36233742bc47ae79f23d2cfae5a0f56dee 100644
> --- a/tools/testing/selftests/vDSO/vdso_config.h
> +++ b/tools/testing/selftests/vDSO/vdso_config.h
> @@ -58,6 +58,7 @@
>  #define VDSO_NAMES		1
>  #endif
>  
> +__attribute__((unused))
>  static const char *versions[7] = {
>  	"LINUX_2.6",
>  	"LINUX_2.6.15",
> @@ -68,6 +69,7 @@ static const char *versions[7] = {
>  	"LINUX_5.10"
>  };
>  
> +__attribute__((unused))
>  static const char *names[2][7] = {
>  	{
>  		"__kernel_gettimeofday",
> 


-- 
Regards,
Usama