mm: update core code to v6.6 upstream
JIRA: https://issues.redhat.com/browse/RHEL-27743
JIRA: https://issues.redhat.com/browse/RHEL-59459
CVE: CVE-2024-46787
Depends: !4961 (merged)
This MR brings RHEL9 core MM code up to upstream's v6.6 LTS level.
This work follows up on the previous v6.5 update (RHEL-27742) and as such,
the bulk of this changeset is comprised of refactoring and clean-ups of
the internal implementation of several APIs as it further advances the
conversion to FOLIOS, and follow up on the per-VMA locking changes.
Also, with the rebase to v6.6 LTS, we complete the infrastructure to allow
Control-flow Enforcement Technology, a.k.a. Shadow Stacks, for x86 builds,
and we add a potential extra level of protection (assessment pending) to help
on mitigating kernel heap exploits dubbed as "SlubStick".
Follow-up fixes are omitted from this series either because they are irrelevant to
the bits we support on RHEL or because they depend on bigger changesets introduced
upstream more recently. A follow-up ticket (RHEL-27745) will deal with these and other cases separately.
Omitted-fix: e540b8c5da04 ("mips: mm: add slab availability checking in ioremap_prot")
Omitted-fix: f7875966dc0c ("tools headers UAPI: Sync files changed by new fchmodat2 and map_shadow_stack syscalls with the kernel sources")
Omitted-fix: df39038cd895 ("s390/mm: Fix VM_FAULT_HWPOISON handling in do_exception()")
Omitted-fix: 12bbaae7635a ("mm: create FOLIO_FLAG_FALSE and FOLIO_TYPE_OPS macros")
Omitted-fix: fd1a745ce03e ("mm: support page_mapcount() on page_has_type() pages")
Omitted-fix: d99e3140a4d3 ("mm: turn folio_test_hugetlb into a PageType")
Omitted-fix: fa2690af573d ("mm: page_ref: remove folio_try_get_rcu()")
Omitted-fix: f442fa614137 ("mm: gup: stop abusing try_grab_folio")
Omitted-fix: cb0f01beb166 ("mm/mprotect: fix dax pud handling")
Signed-off-by: Rafael Aquini raquini@redhat.com