static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
		unsigned long addr, pmd_t *pmdp)
{
	pmd_t old, pmd = *pmdp;

	if (pmd_present(pmd)) {
		/* See comment in change_huge_pmd() */
		old = pmdp_invalidate(vma, addr, pmdp);
		if (pmd_dirty(old))
			pmd = pmd_mkdirty(pmd);
		if (pmd_young(old))
			pmd = pmd_mkyoung(pmd);

		pmd = pmd_wrprotect(pmd);
		pmd = pmd_clear_soft_dirty(pmd);

		set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
	} else if (is_migration_entry(pmd_to_swp_entry(pmd))) {
		pmd = pmd_swp_clear_soft_dirty(pmd);
		set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
	}
}

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.