From: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
[ Upstream commit fda153c89af344d21df281009a9d046cf587ea0f ]
Running the memfd script ./run_hugetlbfs_test.sh will often end in error
as follows:
memfd-hugetlb: CREATE
memfd-hugetlb: BASIC
memfd-hugetlb: SEAL-WRITE
memfd-hugetlb: SEAL-FUTURE-WRITE
memfd-hugetlb: SEAL-SHRINK
fallocate(ALLOC) failed: No space left on device
./run_hugetlbfs_test.sh: line 60: 166855 Aborted (core dumped) ./memfd_test hugetlbfs
opening: ./mnt/memfd
fuse: DONE
If no hugetlb pages have been preallocated, run_hugetlbfs_test.sh will
allocate 'just enough' pages to run the test. In the SEAL-FUTURE-WRITE
test the mfd_fail_write routine maps the file, but does not unmap. As a
result, two hugetlb pages remain reserved for the mapping. When the
fallocate call in the SEAL-SHRINK test attempts allocate all hugetlb
pages, it is short by the two reserved pages.
Fix by making sure to unmap in mfd_fail_write.
Link: https://lkml.kernel.org/r/20220219004340.56478-1-mike.kravetz@xxxxxxxxxx
Signed-off-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Joel Fernandes <joel@xxxxxxxxxxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
tools/testing/selftests/memfd/memfd_test.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/testing/selftests/memfd/memfd_test.c b/tools/testing/selftests/memfd/memfd_test.c
index 334a7eea2004..fba322d1c67a 100644
--- a/tools/testing/selftests/memfd/memfd_test.c
+++ b/tools/testing/selftests/memfd/memfd_test.c
@@ -455,6 +455,7 @@ static void mfd_fail_write(int fd)
printf("mmap()+mprotect() didn't fail as expected\n");
abort();
}
+ munmap(p, mfd_def_size);
}
/* verify PUNCH_HOLE fails */
--
2.34.1
