[PATCH AUTOSEL 5.14 25/40] selftests:kvm: fix get_trans_hugepagesz() ignoring fscanf() return warn

From: Sasha Levin
Date: Tue Sep 28 2021 - 01:57:16 EST


From: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>

[ Upstream commit 3a4f0cc693cd3d80e66a255f0bff0e2c0461eef1 ]

Fix get_trans_hugepagesz() to check fscanf() return value to get rid
of the following warning:

lib/test_util.c: In function ‘get_trans_hugepagesz’:
lib/test_util.c:138:2: warning: ignoring return value of ‘fscanf’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
138 | fscanf(f, "%ld", &size);
| ^~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
Acked-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
tools/testing/selftests/kvm/lib/test_util.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c
index af1031fed97f..938cd423643e 100644
--- a/tools/testing/selftests/kvm/lib/test_util.c
+++ b/tools/testing/selftests/kvm/lib/test_util.c
@@ -129,13 +129,16 @@ size_t get_trans_hugepagesz(void)
{
size_t size;
FILE *f;
+ int ret;

TEST_ASSERT(thp_configured(), "THP is not configured in host kernel");

f = fopen("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size", "r");
TEST_ASSERT(f != NULL, "Error in opening transparent_hugepage/hpage_pmd_size");

- fscanf(f, "%ld", &size);
+ ret = fscanf(f, "%ld", &size);
+ ret = fscanf(f, "%ld", &size);
+ TEST_ASSERT(ret < 1, "Error reading transparent_hugepage/hpage_pmd_size");
fclose(f);

return size;
--
2.33.0