[PATCH 2/2] selftests/vDSO: make vDSO test work on s390x

[Sven Schnelle <svens@linux.ibm.com>]

s390x used 8 byte (Elf64_Xword) sized hash table entries.
Add some code to the vdso test to handle that properly.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
---
 tools/testing/selftests/vDSO/parse_vdso.c | 14 ++++++++++----
 tools/testing/selftests/vDSO/vdso_test.c  | 11 +++++++----
 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/tools/testing/selftests/vDSO/parse_vdso.c b/tools/testing/selftests/vDSO/parse_vdso.c
index 8e5a70a24d9a..2e1e88ebee3d 100644
--- a/tools/testing/selftests/vDSO/parse_vdso.c
+++ b/tools/testing/selftests/vDSO/parse_vdso.c
@@ -58,6 +58,12 @@ extern void *vdso_sym(const char *version, const char *name);
 #define ELF_BITS_XFORM(bits, x) ELF_BITS_XFORM2(bits, x)
 #define ELF(x) ELF_BITS_XFORM(ELF_BITS, x)
 
+#if defined(__s390x__)
+#define	ELF_HASH_TYPE ELF(Xword)
+#else
+#define	ELF_HASH_TYPE ELF(Word)
+#endif
+
 static struct vdso_info
 {
 	bool valid;
@@ -69,8 +75,8 @@ static struct vdso_info
 	/* Symbol table */
 	ELF(Sym) *symtab;
 	const char *symstrings;
-	ELF(Word) *bucket, *chain;
-	ELF(Word) nbucket, nchain;
+	ELF_HASH_TYPE *bucket, *chain;
+	ELF_HASH_TYPE nbucket, nchain;
 
 	/* Version table */
 	ELF(Versym) *versym;
@@ -131,7 +137,7 @@ void vdso_init_from_sysinfo_ehdr(uintptr_t base)
 	/*
 	 * Fish out the useful bits of the dynamic table.
 	 */
-	ELF(Word) *hash = 0;
+	ELF_HASH_TYPE *hash = 0;
 	vdso_info.symstrings = 0;
 	vdso_info.symtab = 0;
 	vdso_info.versym = 0;
@@ -149,7 +155,7 @@ void vdso_init_from_sysinfo_ehdr(uintptr_t base)
 				 + vdso_info.load_offset);
 			break;
 		case DT_HASH:
-			hash = (ELF(Word) *)
+			hash = (ELF_HASH_TYPE *)
 				((uintptr_t)dyn[i].d_un.d_ptr
 				 + vdso_info.load_offset);
 			break;
diff --git a/tools/testing/selftests/vDSO/vdso_test.c b/tools/testing/selftests/vDSO/vdso_test.c
index 719d5a6bd664..2b21261a5eba 100644
--- a/tools/testing/selftests/vDSO/vdso_test.c
+++ b/tools/testing/selftests/vDSO/vdso_test.c
@@ -22,11 +22,14 @@ extern void vdso_init_from_sysinfo_ehdr(uintptr_t base);
 extern void vdso_init_from_auxv(void *auxv);
 
 /*
- * ARM64's vDSO exports its gettimeofday() implementation with a different
- * name and version from other architectures, so we need to handle it as
- * a special case.
+ * Both ARM64's and s390x' vDSO exports its gettimeofday() implementation
+ * with a different name and version from other architectures, so we need
+ * to handle them as a special case.
  */
-#if defined(__aarch64__)
+#if defined(__s390x__)
+const char *version = "LINUX_2.6.29";
+const char *name = "__kernel_gettimeofday";
+#elif defined(__aarch64__)
 const char *version = "LINUX_2.6.39";
 const char *name = "__kernel_gettimeofday";
 #else
-- 
2.17.1