Re: [PATCH v3 08/10] selftests/mm: Skip gup_longerm tests on weird filesystems

From: David Hildenbrand
Date: Thu Mar 06 2025 - 04:28:33 EST


On 28.02.25 17:54, Brendan Jackman wrote:
Some filesystems don't support funtract()ing unlinked files. They return
ENOENT. In that case, skip the test.


That's not documented in the man page, so is this a bug of these filesystems?

What are examples for these weird filesystems?

As we have the fstype available, we could instead simply reject more filesystems earlier. See fs_is_unknown().

Signed-off-by: Brendan Jackman <jackmanb@xxxxxxxxxx>
---
tools/testing/selftests/mm/gup_longterm.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/mm/gup_longterm.c b/tools/testing/selftests/mm/gup_longterm.c
index 879e9e4e8cce8127656fabe098abf7db5f6c5e23..494ec4102111b9c96fb4947b29c184735ceb8e1c 100644
--- a/tools/testing/selftests/mm/gup_longterm.c
+++ b/tools/testing/selftests/mm/gup_longterm.c
@@ -96,7 +96,15 @@ static void do_test(int fd, size_t size, enum test_type type, bool shared)
int ret;
if (ftruncate(fd, size)) {
- ksft_test_result_fail("ftruncate() failed (%s)\n", strerror(errno));
+ if (errno == ENOENT) {
+ /*
+ * This can happen if the file has been unlinked and the
+ * filesystem doesn't support truncating unlinked files.
+ */
+ ksft_test_result_skip("ftruncate() failed with ENOENT\n");
+ } else {
+ ksft_test_result_fail("ftruncate() failed (%s)\n", strerror(errno));
+ }
return;
}



--
Cheers,

David / dhildenb