[PATCH AUTOSEL 4.19 04/30] selftests/ipc: Fix test failure seen after initial test run

Sasha Levin
2020-04-30T14:03:28Z

From: Tyler Hicks <tyhicks@linux.microsoft.com>

[ Upstream commit b87080eab4c1377706c113fc9c0157f19ea8fed1 ]

After successfully running the IPC msgque test once, subsequent runs
result in a test failure:

$ sudo ./run_kselftest.sh
TAP version 13
1..1
# selftests: ipc: msgque
# Failed to get stats for IPC queue with id 0
# Failed to dump queue: -22
# Bail out!
# # Pass 0 Fail 0 Xfail 0 Xpass 0 Skip 0 Error 0
not ok 1 selftests: ipc: msgque # exit=1

The dump_queue() function loops through the possible message queue index
values using calls to msgctl(kern_id, MSG_STAT, ...) where kern_id
represents the index value. The first time the test is ran, the initial
index value of 0 is valid and the test is able to complete. The index
value of 0 is not valid in subsequent test runs and the loop attempts to
try index values of 1, 2, 3, and so on until a valid index value is
found that corresponds to the message queue created earlier in the test.

The msgctl() syscall returns -1 and sets errno to EINVAL when invalid
index values are used. The test failure is caused by incorrectly
comparing errno to -EINVAL when cycling through possible index values.

Fix invalid test failures on subsequent runs of the msgque test by
correctly comparing errno values to a non-negated EINVAL.

Fixes: 3a665531a3b7 ("selftests: IPC message queue copy feature test")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/testing/selftests/ipc/msgque.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/ipc/msgque.c b/tools/testing/selftests/ipc/msgque.c
index 4c156aeab6b80..5ec4d9e18806c 100644
--- a/tools/testing/selftests/ipc/msgque.c
+++ b/tools/testing/selftests/ipc/msgque.c
@@ -137,7 +137,7 @@ int dump_queue(struct msgque_data *msgque)
for (kern_id = 0; kern_id < 256; kern_id++) {
ret = msgctl(kern_id, MSG_STAT, &ds);
if (ret < 0) {
- if (errno == -EINVAL)
+ if (errno == EINVAL)
continue;
printf("Failed to get stats for IPC queue with id %d\n",
kern_id);
--
2.20.1