[PATCH AUTOSEL 4.19 120/123] proc: fixup map_files test on arm

Sasha Levin
2018-12-05T09:42:38Z

From: Alexey Dobriyan <adobriyan@gmail.com>

[ Upstream commit dbd4af54745fc0c805217693c807a3928b2d408b ]

https://bugs.linaro.org/show_bug.cgi?id=3782

Turns out arm doesn't permit mapping address 0, so try minimum virtual
address instead.

Link: http://lkml.kernel.org/r/20181113165446.GA28157@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reported-by: Rafael David Tinoco <rafael.tinoco@linaro.org>
Tested-by: Rafael David Tinoco <rafael.tinoco@linaro.org>
Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/testing/selftests/proc/proc-self-map-files-002.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/proc/proc-self-map-files-002.c b/tools/testing/selftests/proc/proc-self-map-files-002.c
index 6f1f4a6e1ecb..85744425b08d 100644
--- a/tools/testing/selftests/proc/proc-self-map-files-002.c
+++ b/tools/testing/selftests/proc/proc-self-map-files-002.c
@@ -13,7 +13,7 @@
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
-/* Test readlink /proc/self/map_files/... with address 0. */
+/* Test readlink /proc/self/map_files/... with minimum address. */
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
@@ -47,6 +47,11 @@ static void fail(const char *fmt, unsigned long a, unsigned long b)
int main(void)
{
const unsigned int PAGE_SIZE = sysconf(_SC_PAGESIZE);
+#ifdef __arm__
+ unsigned long va = 2 * PAGE_SIZE;
+#else
+ unsigned long va = 0;
+#endif
void *p;
int fd;
unsigned long a, b;
@@ -55,7 +60,7 @@ int main(void)
if (fd == -1)
return 1;

- p = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE|MAP_FIXED, fd, 0);
+ p = mmap((void *)va, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE|MAP_FIXED, fd, 0);
if (p == MAP_FAILED) {
if (errno == EPERM)
return 2;
--
2.17.1