From c08b1c123ffa0ab3a739020827ebb4265f2031ea Mon Sep 17 00:00:00 2001 From: Juhee Kang Date: Tue, 27 Jul 2021 04:10:55 +0000 Subject: [PATCH] samples: bpf: Fix tracex7 error raised on the missing argument [ Upstream commit 7d07006f05922b95518be403f08ef8437b67aa32 ] The current behavior of 'tracex7' doesn't consist with other bpf samples tracex{1..6}. Other samples do not require any argument to run with, but tracex7 should be run with btrfs device argument. (it should be executed with test_override_return.sh) Currently, tracex7 doesn't have any description about how to run this program and raises an unexpected error. And this result might be confusing since users might not have a hunch about how to run this program. // Current behavior # ./tracex7 sh: 1: Syntax error: word unexpected (expecting ")") // Fixed behavior # ./tracex7 ERROR: Run with the btrfs device argument! In order to fix this error, this commit adds logic to report a message and exit when running this program with a missing argument. Additionally in test_override_return.sh, there is a problem with multiple directory(tmpmnt) creation. So in this commit adds a line with removing the directory with every execution. Signed-off-by: Juhee Kang Signed-off-by: Andrii Nakryiko Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20210727041056.23455-1-claudiajkang@gmail.com Signed-off-by: Sasha Levin --- samples/bpf/test_override_return.sh | 1 + samples/bpf/tracex7_user.c | 5 +++++ 2 files changed, 6 insertions(+) diff --git a/samples/bpf/test_override_return.sh b/samples/bpf/test_override_return.sh index e68b9ee6814b..35db26f736b9 100755 --- a/samples/bpf/test_override_return.sh +++ b/samples/bpf/test_override_return.sh @@ -1,5 +1,6 @@ #!/bin/bash +rm -r tmpmnt rm -f testfile.img dd if=/dev/zero of=testfile.img bs=1M seek=1000 count=1 DEVICE=$(losetup --show -f testfile.img) diff --git a/samples/bpf/tracex7_user.c b/samples/bpf/tracex7_user.c index fdcd6580dd73..8be7ce18d3ba 100644 --- a/samples/bpf/tracex7_user.c +++ b/samples/bpf/tracex7_user.c @@ -14,6 +14,11 @@ int main(int argc, char **argv) int ret = 0; FILE *f; + if (!argv[1]) { + fprintf(stderr, "ERROR: Run with the btrfs device argument!\n"); + return 0; + } + snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); obj = bpf_object__open_file(filename, NULL); if (libbpf_get_error(obj)) {