Commit f0ff2447b861 ("selftests/sgx: Add a new kselftest:
Unclobbered_vdso_oversubscribed") depends on __cpuid() without
providing the dependency and thus introduces a build error:
$ make
gcc -Wall -Werror -g -I../../../../tools/include -fPIC -z noexecstack -c main.c -o /path/linux/tools/testing/selftests/sgx/main.o
main.c: In function ‘get_total_epc_mem’:
main.c:296:3: error: implicit declaration of function ‘__cpuid’ [-Werror=implicit-function-declaration]
296 | __cpuid(&eax, &ebx, &ecx, &edx);
| ^~~~~~~
cc1: all warnings being treated as errors
make: *** [Makefile:33: /path/linux/tools/testing/selftests/sgx/main.o] Error 1
$
Make the kernel's __cpuid() available locally in support of the
test's usage.
Fixes: f0ff2447b861 ("selftests/sgx: Add a new kselftest: Unclobbered_vdso_oversubscribed")
Reported-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
Signed-off-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
---
The commit introducing the issue can be found on
the x86/sgx branch of tip.git.
tools/testing/selftests/sgx/main.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/tools/testing/selftests/sgx/main.c b/tools/testing/selftests/sgx/main.c
index 7e912db4c6c5..6dead57a3121 100644
--- a/tools/testing/selftests/sgx/main.c
+++ b/tools/testing/selftests/sgx/main.c
@@ -73,6 +73,18 @@ static bool vdso_get_symtab(void *addr, struct vdso_symtab *symtab)
return true;
}
+static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
+ unsigned int *ecx, unsigned int *edx)
+{
+ asm volatile("cpuid"
+ : "=a" (*eax),
+ "=b" (*ebx),
+ "=c" (*ecx),
+ "=d" (*edx)
+ : "0" (*eax), "2" (*ecx)
+ : "memory");
+}
+
static unsigned long elf_sym_hash(const char *name)
{
unsigned long h = 0, high;
--
2.25.1
