[PATCH v2 14/17] selftests: vdso: Make test_vdso_getrandom look for the right vDSO function

Christophe Leroy
2024-08-22T07:14:29Z

Don't hard-code x86 specific names, use vdso_config definitions
to find the correct function matching the architecture.

Add random VDSO function names in names[][]. Remove the #ifdef
CONFIG_VDSO32, having the name there all the time is harmless
and guaranties a steady index for following strings.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
tools/testing/selftests/vDSO/vdso_config.h | 8 +++-----
tools/testing/selftests/vDSO/vdso_test_getrandom.c | 8 ++++++--
2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/tools/testing/selftests/vDSO/vdso_config.h b/tools/testing/selftests/vDSO/vdso_config.h
index 00bfed6e4922..740ce8c98d2e 100644
--- a/tools/testing/selftests/vDSO/vdso_config.h
+++ b/tools/testing/selftests/vDSO/vdso_config.h
@@ -68,16 +68,15 @@ static const char *versions[7] = {
"LINUX_5.10"
};

-static const char *names[2][6] = {
+static const char *names[2][7] = {
{
"__kernel_gettimeofday",
"__kernel_clock_gettime",
"__kernel_time",
"__kernel_clock_getres",
"__kernel_getcpu",
-#if defined(VDSO_32BIT)
"__kernel_clock_gettime64",
-#endif
+ "__kernel_getrandom",
},
{
"__vdso_gettimeofday",
@@ -85,9 +84,8 @@ static const char *names[2][6] = {
"__vdso_time",
"__vdso_clock_getres",
"__vdso_getcpu",
-#if defined(VDSO_32BIT)
"__vdso_clock_gettime64",
-#endif
+ "__vdso_getrandom",
},
};

diff --git a/tools/testing/selftests/vDSO/vdso_test_getrandom.c b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
index 05122425a873..02bcffc23e0c 100644
--- a/tools/testing/selftests/vDSO/vdso_test_getrandom.c
+++ b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
@@ -21,6 +21,7 @@

#include "../kselftest.h"
#include "parse_vdso.h"
+#include "vdso_config.h"

#ifndef timespecsub
#define timespecsub(tsp, usp, vsp) \
@@ -107,6 +108,9 @@ static void vgetrandom_put_state(void *state)

static void vgetrandom_init(void)
{
+ const char *version = versions[VDSO_VERSION];
+ const char **name = (const char **)&names[VDSO_NAMES];
+
if (pthread_key_create(&grnd_ctx.key, vgetrandom_put_state) != 0)
return;
unsigned long sysinfo_ehdr = getauxval(AT_SYSINFO_EHDR);
@@ -115,9 +119,9 @@ static void vgetrandom_init(void)
exit(KSFT_SKIP);
}
vdso_init_from_sysinfo_ehdr(sysinfo_ehdr);
- grnd_ctx.fn = (__typeof__(grnd_ctx.fn))vdso_sym("LINUX_2.6", "__vdso_getrandom");
+ grnd_ctx.fn = (__typeof__(grnd_ctx.fn))vdso_sym(version, name[6]);
if (!grnd_ctx.fn) {
- printf("__vdso_getrandom is missing!\n");
+ printf("%s is missing!\n", name[6]);
exit(KSFT_FAIL);
}
if (grnd_ctx.fn(NULL, 0, 0, &grnd_ctx.params, ~0UL) != 0) {
--
2.44.0