linux.git/include/linux/userfaultfd_k.h, branch v7.1-rc3

shmem, userfaultfd: implement shmem uffd operations using vm_uffd_ops

2026-04-18T07:10:54+00:00

Add filemap_add() and filemap_remove() methods to vm_uffd_ops and use them
in __mfill_atomic_pte() to add shmem folios to page cache and remove them
in case of error.

Implement these methods in shmem along with vm_uffd_ops->alloc_folio() and
drop shmem_mfill_atomic_pte().

Since userfaultfd now does not reference any functions from shmem, drop
include if linux/shmem_fs.h from mm/userfaultfd.c

mfill_atomic_install_pte() is not used anywhere outside of mm/userfaultfd,
make it static.

Link: https://lore.kernel.org/20260402041156.1377214-11-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) 
Reviewed-by: James Houghton 
Cc: Andrea Arcangeli 
Cc: Andrei Vagin 
Cc: Axel Rasmussen 
Cc: Baolin Wang 
Cc: David Hildenbrand (Arm) 
Cc: Harry Yoo 
Cc: Harry Yoo (Oracle) 
Cc: Hugh Dickins 
Cc: Liam Howlett 
Cc: Lorenzo Stoakes (Oracle) 
Cc: Matthew Wilcox (Oracle) 
Cc: Michal Hocko 
Cc: Muchun Song 
Cc: Nikita Kalyazin 
Cc: Oscar Salvador 
Cc: Paolo Bonzini 
Cc: Peter Xu 
Cc: Sean Christopherson 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Cc: David Carlier 
Signed-off-by: Andrew Morton

userfaultfd: introduce vm_uffd_ops->alloc_folio()

2026-04-18T07:10:54+00:00

and use it to refactor mfill_atomic_pte_zeroed_folio() and
mfill_atomic_pte_copy().

mfill_atomic_pte_zeroed_folio() and mfill_atomic_pte_copy() perform
almost identical actions:
* allocate a folio
* update folio contents (either copy from userspace of fill with zeros)
* update page tables with the new folio

Split a __mfill_atomic_pte() helper that handles both cases and uses newly
introduced vm_uffd_ops->alloc_folio() to allocate the folio.

Pass the ops structure from the callers to __mfill_atomic_pte() to later
allow using anon_uffd_ops for MAP_PRIVATE mappings of file-backed VMAs.

Note, that the new ops method is called alloc_folio() rather than
folio_alloc() to avoid clash with alloc_tag macro folio_alloc().

Link: https://lore.kernel.org/20260402041156.1377214-10-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) 
Reviewed-by: James Houghton 
Cc: Andrea Arcangeli 
Cc: Andrei Vagin 
Cc: Axel Rasmussen 
Cc: Baolin Wang 
Cc: David Hildenbrand (Arm) 
Cc: Harry Yoo 
Cc: Harry Yoo (Oracle) 
Cc: Hugh Dickins 
Cc: Liam Howlett 
Cc: Lorenzo Stoakes (Oracle) 
Cc: Matthew Wilcox (Oracle) 
Cc: Michal Hocko 
Cc: Muchun Song 
Cc: Nikita Kalyazin 
Cc: Oscar Salvador 
Cc: Paolo Bonzini 
Cc: Peter Xu 
Cc: Sean Christopherson 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Cc: David Carlier 
Signed-off-by: Andrew Morton

shmem, userfaultfd: use a VMA callback to handle UFFDIO_CONTINUE

2026-04-18T07:10:54+00:00

When userspace resolves a page fault in a shmem VMA with UFFDIO_CONTINUE
it needs to get a folio that already exists in the pagecache backing that
VMA.

Instead of using shmem_get_folio() for that, add a get_folio_noalloc()
method to 'struct vm_uffd_ops' that will return a folio if it exists in
the VMA's pagecache at given pgoff.

Implement get_folio_noalloc() method for shmem and slightly refactor
userfaultfd's mfill_get_vma() and mfill_atomic_pte_continue() to support
this new API.

Link: https://lore.kernel.org/20260402041156.1377214-9-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) 
Reviewed-by: James Houghton 
Cc: Andrea Arcangeli 
Cc: Andrei Vagin 
Cc: Axel Rasmussen 
Cc: Baolin Wang 
Cc: David Hildenbrand (Arm) 
Cc: Harry Yoo 
Cc: Harry Yoo (Oracle) 
Cc: Hugh Dickins 
Cc: Liam Howlett 
Cc: Lorenzo Stoakes (Oracle) 
Cc: Matthew Wilcox (Oracle) 
Cc: Michal Hocko 
Cc: Muchun Song 
Cc: Nikita Kalyazin 
Cc: Oscar Salvador 
Cc: Paolo Bonzini 
Cc: Peter Xu 
Cc: Sean Christopherson 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Cc: David Carlier 
Signed-off-by: Andrew Morton

userfaultfd: introduce vm_uffd_ops

2026-04-18T07:10:53+00:00

Current userfaultfd implementation works only with memory managed by core
MM: anonymous, shmem and hugetlb.

First, there is no fundamental reason to limit userfaultfd support only to
the core memory types and userfaults can be handled similarly to regular
page faults provided a VMA owner implements appropriate callbacks.

Second, historically various code paths were conditioned on
vma_is_anonymous(), vma_is_shmem() and is_vm_hugetlb_page() and some of
these conditions can be expressed as operations implemented by a
particular memory type.

Introduce vm_uffd_ops extension to vm_operations_struct that will delegate
memory type specific operations to a VMA owner.

Operations for anonymous memory are handled internally in userfaultfd
using anon_uffd_ops that implicitly assigned to anonymous VMAs.

Start with a single operation, ->can_userfault() that will verify that a
VMA meets requirements for userfaultfd support at registration time.

Implement that method for anonymous, shmem and hugetlb and move relevant
parts of vma_can_userfault() into the new callbacks.

[rppt@kernel.org: relocate VM_DROPPABLE test, per Tal]
  Link: https://lore.kernel.org/adffgfM5ANxtPIEF@kernel.org
Link: https://lore.kernel.org/20260402041156.1377214-8-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) 
Cc: Andrea Arcangeli 
Cc: Andrei Vagin 
Cc: Axel Rasmussen 
Cc: Baolin Wang 
Cc: David Hildenbrand (Arm) 
Cc: Harry Yoo 
Cc: Harry Yoo (Oracle) 
Cc: Hugh Dickins 
Cc: James Houghton 
Cc: Liam Howlett 
Cc: Lorenzo Stoakes (Oracle) 
Cc: Matthew Wilcox (Oracle) 
Cc: Michal Hocko 
Cc: Muchun Song 
Cc: Nikita Kalyazin 
Cc: Oscar Salvador 
Cc: Paolo Bonzini 
Cc: Peter Xu 
Cc: Sean Christopherson 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Cc: David Carlier 
Cc: Tal Zussman 
Signed-off-by: Andrew Morton

userfaultfd: move vma_can_userfault out of line

2026-04-18T07:10:53+00:00

vma_can_userfault() has grown pretty big and it's not called on
performance critical path.

Move it out of line.

No functional changes.

Link: https://lore.kernel.org/20260402041156.1377214-7-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) 
Reviewed-by: David Hildenbrand (Red Hat) 
Reviewed-by: Liam R. Howlett 
Cc: Andrea Arcangeli 
Cc: Andrei Vagin 
Cc: Axel Rasmussen 
Cc: Baolin Wang 
Cc: Harry Yoo 
Cc: Harry Yoo (Oracle) 
Cc: Hugh Dickins 
Cc: James Houghton 
Cc: Lorenzo Stoakes (Oracle) 
Cc: Matthew Wilcox (Oracle) 
Cc: Michal Hocko 
Cc: Muchun Song 
Cc: Nikita Kalyazin 
Cc: Oscar Salvador 
Cc: Paolo Bonzini 
Cc: Peter Xu 
Cc: Sean Christopherson 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Cc: David Carlier 
Signed-off-by: Andrew Morton

mm/vma: convert vma_modify_flags[_uffd]() to use vma_flags_t

2026-04-05T20:53:41+00:00

Update the vma_modify_flags() and vma_modify_flags_uffd() functions to
accept a vma_flags_t parameter rather than a vm_flags_t one, and propagate
the changes as needed to implement this change.

Also add vma_flags_reset_once() in replacement of vm_flags_reset_once(). We
still need to be careful here because we need to avoid tearing, so maintain
the assumption that the first system word set of flags are the only ones
that require protection from tearing, and retain this functionality.

We can copy the remainder of VMA flags above 64 bits normally. But
hopefully by the time that happens, we will have replaced the logic that
requires these WRITE_ONCE()'s with something else.

We also replace instances of vm_flags_reset() with a simple write of VMA
flags. We are no longer perform a number of checks, most notable of all the
VMA flags asserts becase:

1. We might be operating on a VMA that is not yet added to the tree.

2. We might be operating on a VMA that is now detached.

3. Really in all but core code, you should be using vma_desc_xxx().

4. Other VMA fields are manipulated with no such checks.

5. It'd be egregious to have to add variants of flag functions just to
   account for cases such as the above, especially when we don't do so for
   other VMA fields. Drivers are the problematic cases and why it was
   especially important (and also for debug as VMA locks were introduced),
   the mmap_prepare work is solving this generally.

Additionally, we can fairly safely assume by this point the soft dirty
flags are being set correctly, so it's reasonable to drop this also.

Finally, update the VMA tests to reflect this.

Link: https://lkml.kernel.org/r/51afbb2b8c3681003cc7926647e37335d793836e.1774034900.git.ljs@kernel.org
Signed-off-by: Lorenzo Stoakes (Oracle) 
Acked-by: Vlastimil Babka (SUSE) 
Cc: Albert Ou 
Cc: Alexander Gordeev 
Cc: Alexandre Ghiti 
Cc: Al Viro 
Cc: Anton Ivanov 
Cc: "Borislav Petkov (AMD)" 
Cc: Catalin Marinas 
Cc: Chengming Zhou 
Cc: Christian Borntraeger 
Cc: Christian Brauner 
Cc: David Hildenbrand 
Cc: Dinh Nguyen 
Cc: Heiko Carstens 
Cc: "H. Peter Anvin" 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Jan Kara 
Cc: Jann Horn 
Cc: Johannes Berg 
Cc: Kees Cook 
Cc: Liam Howlett 
Cc: Madhavan Srinivasan 
Cc: Michael Ellerman 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Nicholas Piggin 
Cc: Ondrej Mosnacek 
Cc: Palmer Dabbelt 
Cc: Paul Moore 
Cc: Pedro Falcato 
Cc: Richard Weinberger 
Cc: Russell King 
Cc: Stephen Smalley 
Cc: Suren Baghdasaryan 
Cc: Sven Schnelle 
Cc: Thomas Bogendoerfer 
Cc: Vasily Gorbik 
Cc: Vineet Gupta 
Cc: WANG Xuerui 
Cc: Will Deacon 
Cc: xu xin 
Signed-off-by: Andrew Morton

mm: userfaultfd: add pgtable_supports_uffd_wp()

2025-11-24T23:08:54+00:00

Some platforms can customize the PTE/PMD entry uffd-wp bit making it
unavailable even if the architecture provides the resource.  This patch
adds a macro API pgtable_supports_uffd_wp() that allows architectures to
define their specific implementations to check if the uffd-wp bit is
available on which device the kernel is running.

Also this patch is removing "ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP" and
"ifdef CONFIG_PTE_MARKER_UFFD_WP" in favor of pgtable_supports_uffd_wp()
and uffd_supports_wp_marker() checks respectively that default to
IS_ENABLED(CONFIG_HAVE_ARCH_USERFAULTFD_WP) and
"IS_ENABLED(CONFIG_HAVE_ARCH_USERFAULTFD_WP) &&
IS_ENABLED(CONFIG_PTE_MARKER_UFFD_WP)" if not overridden by the
architecture, no change in behavior is expected.

Link: https://lkml.kernel.org/r/20251113072806.795029-3-zhangchunyan@iscas.ac.cn
Signed-off-by: Chunyan Zhang 
Acked-by: David Hildenbrand 
Cc: Albert Ou 
Cc: Alexandre Ghiti 
Cc: Alexandre Ghiti 
Cc: Al Viro 
Cc: Andrew Jones 
Cc: Arnd Bergmann 
Cc: Axel Rasmussen 
Cc: Christian Brauner 
Cc: Conor Dooley 
Cc: Conor Dooley 
Cc: Deepak Gupta 
Cc: Jan Kara 
Cc: Liam Howlett 
Cc: Lorenzo Stoakes 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Palmer Dabbelt 
Cc: Paul Walmsley 
Cc: Peter Xu 
Cc: Rob Herring 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Cc: Yuanchu Xie 
Signed-off-by: Andrew Morton

mm: avoid unnecessary uses of is_swap_pte()

2025-11-24T23:08:50+00:00

There's an established convention in the kernel that we treat PTEs as
containing swap entries (and the unfortunately named non-swap swap
entries) should they be neither empty (i.e.  pte_none() evaluating true)
nor present (i.e.  pte_present() evaluating true).

However, there is some inconsistency in how this is applied, as we also
have the is_swap_pte() helper which explicitly performs this check:

	/* check whether a pte points to a swap entry */
	static inline int is_swap_pte(pte_t pte)
	{
		return !pte_none(pte) && !pte_present(pte);
	}

As this represents a predicate, and it's logical to assume that in order
to establish that a PTE entry can correctly be manipulated as a
swap/non-swap entry, this predicate seems as if it must first be checked.

But we instead, we far more often utilise the established convention of
checking pte_none() / pte_present() before operating on entries as if they
were swap/non-swap.

This patch works towards correcting this inconsistency by removing all
uses of is_swap_pte() where we are already in a position where we perform
pte_none()/pte_present() checks anyway or otherwise it is clearly logical
to do so.

We also take advantage of the fact that pte_swp_uffd_wp() is only set on
swap entries.

Additionally, update comments referencing to is_swap_pte() and
non_swap_entry().

No functional change intended.

Link: https://lkml.kernel.org/r/17fd6d7f46a846517fd455fadd640af47fcd7c55.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes 
Reviewed-by: Zi Yan 
Reviewed-by: Vlastimil Babka 
Cc: Alexander Gordeev 
Cc: Alistair Popple 
Cc: Al Viro 
Cc: Arnd Bergmann 
Cc: Axel Rasmussen 
Cc: Baolin Wang 
Cc: Baoquan He 
Cc: Barry Song 
Cc: Byungchul Park 
Cc: Chengming Zhou 
Cc: Chris Li 
Cc: Christian Borntraeger 
Cc: Christian Brauner 
Cc: Claudio Imbrenda 
Cc: David Hildenbrand 
Cc: Dev Jain 
Cc: Gerald Schaefer 
Cc: Gregory Price 
Cc: Heiko Carstens 
Cc: "Huang, Ying" 
Cc: Hugh Dickins 
Cc: Jan Kara 
Cc: Jann Horn 
Cc: Janosch Frank 
Cc: Jason Gunthorpe 
Cc: Joshua Hahn 
Cc: Kairui Song 
Cc: Kemeng Shi 
Cc: Lance Yang 
Cc: Leon Romanovsky 
Cc: Liam Howlett 
Cc: Mathew Brost 
Cc: Matthew Wilcox (Oracle) 
Cc: Miaohe Lin 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Muchun Song 
Cc: Naoya Horiguchi 
Cc: Nhat Pham 
Cc: Nico Pache 
Cc: Oscar Salvador 
Cc: Pasha Tatashin 
Cc: Peter Xu 
Cc: Rakie Kim 
Cc: Rik van Riel 
Cc: Ryan Roberts 
Cc: SeongJae Park 
Cc: Suren Baghdasaryan 
Cc: Sven Schnelle 
Cc: Vasily Gorbik 
Cc: Wei Xu 
Cc: xu xin 
Cc: Yuanchu Xie 
Signed-off-by: Andrew Morton

mm: introduce leaf entry type and use to simplify leaf entry logic

2025-11-24T23:08:50+00:00

The kernel maintains leaf page table entries which contain either:

The kernel maintains leaf page table entries which contain either:

 - Nothing ('none' entries)
 - Present entries*
 - Everything else that will cause a fault which the kernel handles

* Present entries are either entries the hardware can navigate without page
  fault or special cases like NUMA hint protnone or PMD with cleared
  present bit which contain hardware-valid entries modulo the present bit.

In the 'everything else' group we include swap entries, but we also
include a number of other things such as migration entries, device private
entries and marker entries.

Unfortunately this 'everything else' group expresses everything through a
swp_entry_t type, and these entries are referred to swap entries even
though they may well not contain a...  swap entry.

This is compounded by the rather mind-boggling concept of a non-swap swap
entry (checked via non_swap_entry()) and the means by which we twist and
turn to satisfy this.

This patch lays the foundation for reducing this confusion.

We refer to 'everything else' as a 'software-define leaf entry' or
'softleaf'.  for short And in fact we scoop up the 'none' entries into
this concept also so we are left with:

- Present entries.
- Softleaf entries (which may be empty).

This allows for radical simplification across the board - one can simply
convert any leaf page table entry to a leaf entry via softleaf_from_pte().

If the entry is present, we return an empty leaf entry, so it is assumed
the caller is aware that they must differentiate between the two
categories of page table entries, checking for the former via
pte_present().

As a result, we can eliminate a number of places where we would otherwise
need to use predicates to see if we can proceed with leaf page table entry
conversion and instead just go ahead and do it unconditionally.

We do so where we can, adjusting surrounding logic as necessary to
integrate the new softleaf_t logic as far as seems reasonable at this
stage.

We typedef swp_entry_t to softleaf_t for the time being until the
conversion can be complete, meaning everything remains compatible
regardless of which type is used.  We will eventually remove swp_entry_t
when the conversion is complete.

We introduce a new header file to keep things clear - leafops.h - this
imports swapops.h so can direct replace swapops imports without issue, and
we do so in all the files that require it.

Additionally, add new leafops.h file to core mm maintainers entry.

Link: https://lkml.kernel.org/r/c879383aac77d96a03e4d38f7daba893cd35fc76.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes 
Acked-by: Zi Yan 
Reviewed-by: Vlastimil Babka 
Cc: Alexander Gordeev 
Cc: Alistair Popple 
Cc: Al Viro 
Cc: Arnd Bergmann 
Cc: Axel Rasmussen 
Cc: Baolin Wang 
Cc: Baoquan He 
Cc: Barry Song 
Cc: Byungchul Park 
Cc: Chengming Zhou 
Cc: Chris Li 
Cc: Christian Borntraeger 
Cc: Christian Brauner 
Cc: Claudio Imbrenda 
Cc: David Hildenbrand 
Cc: Dev Jain 
Cc: Gerald Schaefer 
Cc: Gregory Price 
Cc: Heiko Carstens 
Cc: "Huang, Ying" 
Cc: Hugh Dickins 
Cc: Jan Kara 
Cc: Jann Horn 
Cc: Janosch Frank 
Cc: Jason Gunthorpe 
Cc: Joshua Hahn 
Cc: Kairui Song 
Cc: Kemeng Shi 
Cc: Lance Yang 
Cc: Leon Romanovsky 
Cc: Liam Howlett 
Cc: Mathew Brost 
Cc: Matthew Wilcox (Oracle) 
Cc: Miaohe Lin 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Muchun Song 
Cc: Naoya Horiguchi 
Cc: Nhat Pham 
Cc: Nico Pache 
Cc: Oscar Salvador 
Cc: Pasha Tatashin 
Cc: Peter Xu 
Cc: Rakie Kim 
Cc: Rik van Riel 
Cc: Ryan Roberts 
Cc: SeongJae Park 
Cc: Suren Baghdasaryan 
Cc: Sven Schnelle 
Cc: Vasily Gorbik 
Cc: Wei Xu 
Cc: xu xin 
Cc: Yuanchu Xie 
Signed-off-by: Andrew Morton

mm: correctly handle UFFD PTE markers

2025-11-24T23:08:50+00:00

Patch series "mm: remove is_swap_[pte, pmd]() + non-swap entries,
introduce leaf entries", v3.

There's an established convention in the kernel that we treat leaf page
tables (so far at the PTE, PMD level) as containing 'swap entries' should
they be neither empty (i.e.  p**_none() evaluating true) nor present (i.e.
p**_present() evaluating true).

However, at the same time we also have helper predicates - is_swap_pte(),
is_swap_pmd() - which are inconsistently used.

This is problematic, as it is logical to assume that should somebody wish
to operate upon a page table swap entry they should first check to see if
it is in fact one.

It also implies that perhaps, in future, we might introduce a non-present,
none page table entry that is not a swap entry.

This series resolves this issue by systematically eliminating all use of
the is_swap_pte() and is swap_pmd() predicates so we retain only the
convention that should a leaf page table entry be neither none nor present
it is a swap entry.

We also have the further issue that 'swap entry' is unfortunately a really
rather overloaded term and in fact refers to both entries for swap and for
other information such as migration entries, page table markers, and
device private entries.

We therefore have the rather 'unique' concept of a 'non-swap' swap entry.

This series therefore introduces the concept of 'software leaf entries',
of type softleaf_t, to eliminate this confusion.

A software leaf entry in this sense is any page table entry which is
non-present, and represented by the softleaf_t type.  That is - page table
leaf entries which are software-controlled by the kernel.

This includes 'none' or empty entries, which are simply represented by an
zero leaf entry value.

In order to maintain compatibility as we transition the kernel to this new
type, we simply typedef swp_entry_t to softleaf_t.

We introduce a number of predicates and helpers to interact with software
leaf entries in include/linux/leafops.h which, as it imports swapops.h,
can be treated as a drop-in replacement for swapops.h wherever leaf entry
helpers are used.

Since softleaf_from_[pte, pmd]() treats present entries as they were
empty/none leaf entries, this allows for a great deal of simplification of
code throughout the code base, which this series utilises a great deal.

We additionally change from swap entry to software leaf entry handling
where it makes sense to and eliminate functions from swapops.h where
software leaf entries obviate the need for the functions.


This patch (of 16):

PTE markers were previously only concerned with UFFD-specific logic - that
is, PTE entries with the UFFD WP marker set or those marked via
UFFDIO_POISON.

However since the introduction of guard markers in commit 7c53dfbdb024
("mm: add PTE_MARKER_GUARD PTE marker"), this has no longer been the case.

Issues have been avoided as guard regions are not permitted in conjunction
with UFFD, but it still leaves very confusing logic in place, most notably
the misleading and poorly named pte_none_mostly() and
huge_pte_none_mostly().

This predicate returns true for PTE entries that ought to be treated as
none, but only in certain circumstances, and on the assumption we are
dealing with H/W poison markers or UFFD WP markers.

This patch removes these functions and makes each invocation of these
functions instead explicitly check what it needs to check.

As part of this effort it introduces is_uffd_pte_marker() to explicitly
determine if a marker in fact is used as part of UFFD or not.

In the HMM logic we note that the only time we would need to check for a
fault is in the case of a UFFD WP marker, otherwise we simply encounter a
fault error (VM_FAULT_HWPOISON for H/W poisoned marker, VM_FAULT_SIGSEGV
for a guard marker), so only check for the UFFD WP case.

While we're here we also refactor code to make it easier to understand.

[akpm@linux-foundation.org: fix comment typo, per Mike]
Link: https://lkml.kernel.org/r/cover.1762812360.git.lorenzo.stoakes@oracle.com
Link: https://lkml.kernel.org/r/c38625fd9a1c1f1cf64ae8a248858e45b3dcdf11.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes 
Reviewed-by: Vlastimil Babka 
Reviewed-by: Mike Rapoport (Microsoft) 
Cc: Alexander Gordeev 
Cc: Alistair Popple 
Cc: Al Viro 
Cc: Arnd Bergmann 
Cc: Axel Rasmussen 
Cc: Baolin Wang 
Cc: Baoquan He 
Cc: Barry Song 
Cc: Byungchul Park 
Cc: Chengming Zhou 
Cc: Chris Li 
Cc: Christian Borntraeger 
Cc: Christian Brauner 
Cc: Claudio Imbrenda 
Cc: David Hildenbrand 
Cc: Dev Jain 
Cc: Gerald Schaefer 
Cc: Gregory Price 
Cc: Heiko Carstens 
Cc: "Huang, Ying" 
Cc: Hugh Dickins 
Cc: Jan Kara 
Cc: Jann Horn 
Cc: Janosch Frank 
Cc: Jason Gunthorpe 
Cc: Joshua Hahn 
Cc: Kairui Song 
Cc: Kemeng Shi 
Cc: Lance Yang 
Cc: Leon Romanovsky 
Cc: Liam Howlett 
Cc: Mathew Brost 
Cc: Matthew Wilcox (Oracle) 
Cc: Miaohe Lin 
Cc: Michal Hocko 
Cc: Muchun Song 
Cc: Naoya Horiguchi 
Cc: Nhat Pham 
Cc: Nico Pache 
Cc: Oscar Salvador 
Cc: Pasha Tatashin 
Cc: Peter Xu 
Cc: Rakie Kim 
Cc: Rik van Riel 
Cc: Ryan Roberts 
Cc: SeongJae Park 
Cc: Suren Baghdasaryan 
Cc: Sven Schnelle 
Cc: Vasily Gorbik 
Cc: Wei Xu 
Cc: xu xin 
Cc: Yuanchu Xie 
Cc: Zi Yan 
Signed-off-by: Andrew Morton