Re: [LTP] hugetlb/hugemmap: add hugemmap33 to test hugetlbfs quota accounting

[linuxtestproject.agent@gmail.com]

Hi Pavithra,

On Wed Sep 9 14:25:55 2026 +0530, Pavithra <pavrampu@linux.ibm.com> wrote:
> hugetlb/hugemmap: add hugemmap33 to test hugetlbfs quota accounting

> Test hugetlbfs quota accounting with filesystem size limits to check
> for regressions in quota handling for MAP_PRIVATE and MAP_SHARED pages.

The empty lines in the commit message body contain trailing whitespace,
which triggers checkpatch errors.

> +/*\
> + * Test hugetlbfs quota accounting with filesystem size limits.
> + *
> + * The number of global huge pages available to a mounted hugetlbfs filesystem
> + * can be limited using a quota mechanism by setting the size attribute at
> + * mount time. Older kernels did not properly handle quota accounting for
> + * MAP_PRIVATE pages and MAP_SHARED reservations.
> + *
> + * Commit a1e78772d72b introduced MAP_PRIVATE reservations at mmap() time,
> + * so quota is checked upfront and mmap() fails with ENOMEM when over quota.
> + * Before this, quota was only checked at fault time resulting in SIGBUS.
> + *
> + * Root is required to mount the quota-limited hugetlbfs instance.
> + */

Use :manpage:`mmap(2)` when referencing mmap() in the documentation block.

> +static void verify_quota_map_unmap(unsigned long size, int mmap_flags)
> +{
> +	int fd;
> +	char path[PATH_MAX];
> +
> +	snprintf(path, sizeof(path), "%s/test_file_%d", MNTPOINT, getpid());
> +	fd = SAFE_OPEN(path, O_CREAT | O_RDWR, 0600);
> +	SAFE_UNLINK(path);
> +
> +	TST_EXP_PASS_PTR_VOID(mmap(NULL, size, PROT_READ | PROT_WRITE, mmap_flags, fd, 0),
> +			       "mmap untouched mapping");
> +	SAFE_CLOSE(fd);
> +}

verify_quota_map_unmap() never unmaps the mapping. As a result, this
tests cleanup on process termination rather than unmapping an untouched
mapping. Call SAFE_MUNMAP(TST_RET_PTR, size) if TST_PASS before closing fd.

> +	snprintf(path, sizeof(path), "%s/test_file_%d", MNTPOINT, getpid());
> +	fd = SAFE_OPEN(path, O_CREAT | O_RDWR, 0600);
> +	SAFE_UNLINK(path);

Use tst_creat_unlinked(MNTPOINT, 0, 0600) instead of manually creating and
unlinking files across the test functions.

> +	if (mount("none", MNTPOINT, "hugetlbfs", 0, mount_opts) == -1) {
> +		if (errno == ENODEV)
> +			tst_brk(TCONF, "hugetlbfs not supported");
> +		tst_brk(TBROK | TERRNO, "mount() failed");
> +	}

Use SAFE_MOUNT("none", MNTPOINT, "hugetlbfs", 0, mount_opts). Hugepage
support is already checked by .hugepages before setup() runs.

Verdict - Needs revision

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