linux-toradex.git/drivers/pci/p2pdma.c, branch v7.2-rc5 Linux kernel for Apalis and Colibri modules PCI/P2PDMA: Add Intel QAT, DSA, IAA devices to whitelist 2026-06-09T22:04:02+00:00 Lukas Wunner lukas@wunner.de 2026-06-04T15:12:08+00:00 0ba76b19fd4c7256787eab0283c759b18eb76876 The first device on a PCI root bus determines whether the host bridge is whitelisted for P2PDMA. All Intel Xeon chips since Ice Lake (ICX, 2021) expose a device with ID 0x09a2 as first device. It is loosely associated with the IOMMU. All these Xeon chips support P2PDMA, so since the addition of the device with commit feaea1fe8b36 ("PCI/P2PDMA: Add Intel 3rd Gen Intel Xeon Scalable Processors to whitelist"), P2PDMA has been allowed on all new Xeons without the need to amend the whitelist: Xeons with Performance Cores: Sapphire Rapids (SPR, 2023) Emerald Rapids (EMR, 2023) Granite Rapids (GNR, 2024) Diamond Rapids (DMR, 2026) Xeons with Efficiency Cores: Sierra Forest (SRF, 2024) Clearwater Forest (CWF, 2026) However these Xeons also expose accelerators as first device on a root bus of its own: QuickAssist Technology (QAT, crypto & compression accelerator) Data Streaming Accelerator (DSA, dma engine) In-Memory Analytics Accelerator (IAA, compression accelerator) Whitelist them for P2PDMA as well. Move their Device ID macros from the accelerator drivers to <linux/pci_ids.h> for reuse by P2PDMA code. Unfortunately the Device IDs vary across Xeon generations as additional features were added to the accelerators. This currently necessitates an amendment for each new Xeon chip. For future chips, this need shall be avoided by an ongoing effort to extend ACPI HMAT with PCIe P2PDMA characteristics (latency, bandwidth, ordering constraints). The PCI core will be able look up in this BIOS-provided ACPI table whether P2PDMA is supported, instead of relying on a whitelist that needs to be amended continuously. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com> Acked-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com> # QAT Cc: stable@vger.kernel.org Link: https://patch.msgid.link/6aac4922b5fe7070b11874427a9285e42ddd05a4.1780585518.git.lukas@wunner.de 
The first device on a PCI root bus determines whether the host bridge is
whitelisted for P2PDMA.  All Intel Xeon chips since Ice Lake (ICX, 2021)
expose a device with ID 0x09a2 as first device.  It is loosely associated
with the IOMMU.  All these Xeon chips support P2PDMA, so since the addition
of the device with commit feaea1fe8b36 ("PCI/P2PDMA: Add Intel 3rd Gen
Intel Xeon Scalable Processors to whitelist"), P2PDMA has been allowed on
all new Xeons without the need to amend the whitelist:

Xeons with Performance Cores:
  Sapphire Rapids (SPR, 2023)
  Emerald Rapids (EMR, 2023)
  Granite Rapids (GNR, 2024)
  Diamond Rapids (DMR, 2026)

Xeons with Efficiency Cores:
  Sierra Forest (SRF, 2024)
  Clearwater Forest (CWF, 2026)

However these Xeons also expose accelerators as first device on a root bus
of its own:

  QuickAssist Technology (QAT, crypto & compression accelerator)
  Data Streaming Accelerator (DSA, dma engine)
  In-Memory Analytics Accelerator (IAA, compression accelerator)

Whitelist them for P2PDMA as well.  Move their Device ID macros from the
accelerator drivers to <linux/pci_ids.h> for reuse by P2PDMA code.

Unfortunately the Device IDs vary across Xeon generations as additional
features were added to the accelerators.  This currently necessitates an
amendment for each new Xeon chip.

For future chips, this need shall be avoided by an ongoing effort to extend
ACPI HMAT with PCIe P2PDMA characteristics (latency, bandwidth, ordering
constraints).  The PCI core will be able look up in this BIOS-provided ACPI
table whether P2PDMA is supported, instead of relying on a whitelist that
needs to be amended continuously.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Acked-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com> # QAT
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/6aac4922b5fe7070b11874427a9285e42ddd05a4.1780585518.git.lukas@wunner.de
PCI/P2PDMA: Avoid returning a provider for non_mappable_bars 2026-04-27T14:47:24+00:00 Matt Evans mattev@meta.com 2026-04-23T17:30:51+00:00 951ebc18d181af1d90deddbc0ef3269061d6e03c Extend the checks in pcim_p2pdma_init() and pcim_p2pdma_provider() to exclude functions that have pdev->non_mappable_bars set. Consumers such as VFIO were previously able to map these for access by the CPU or P2P. Update the comment on non_mappable_bars to show it refers to any access, not just userspace CPU access. Fixes: 372d6d1b8ae3c ("PCI/P2PDMA: Refactor to separate core P2P functionality from memory allocation") Suggested-by: Alex Williamson <alex@shazbot.org> Signed-off-by: Matt Evans <mattev@meta.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Reviewed-by: Alex Williamson <alex@shazbot.org> Link: https://patch.msgid.link/20260423173051.1999679-1-mattev@meta.com 
Extend the checks in pcim_p2pdma_init() and pcim_p2pdma_provider() to
exclude functions that have pdev->non_mappable_bars set.

Consumers such as VFIO were previously able to map these for access by the
CPU or P2P.  Update the comment on non_mappable_bars to show it refers to
any access, not just userspace CPU access.

Fixes: 372d6d1b8ae3c ("PCI/P2PDMA: Refactor to separate core P2P functionality from memory allocation")
Suggested-by: Alex Williamson <alex@shazbot.org>
Signed-off-by: Matt Evans <mattev@meta.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Alex Williamson <alex@shazbot.org>
Link: https://patch.msgid.link/20260423173051.1999679-1-mattev@meta.com
PCI/P2PDMA: Add Google SoCs to the P2P DMA host bridge list 2026-04-10T22:27:39+00:00 Jacob Moroni jmoroni@google.com 2026-04-09T15:01:23+00:00 70cf146a674c447753ceeb34246ad0afdd0064bb All Google SoCs support peer-to-peer DMA between Root Ports, so add a wildcard rule to the host bridge list. Signed-off-by: Jacob Moroni <jmoroni@google.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: David Hu <xuehaohu@google.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Link: https://patch.msgid.link/20260409150123.3538444-2-jmoroni@google.com 
All Google SoCs support peer-to-peer DMA between Root Ports, so add a
wildcard rule to the host bridge list.

Signed-off-by: Jacob Moroni <jmoroni@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: David Hu <xuehaohu@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Link: https://patch.msgid.link/20260409150123.3538444-2-jmoroni@google.com
PCI/P2PDMA: Allow wildcard Device IDs in host bridge list 2026-04-10T22:27:15+00:00 Jacob Moroni jmoroni@google.com 2026-04-09T15:01:22+00:00 1a1f96e3e2a8dc1774c626bc6e15944c3e160393 Currently, the pci_p2pdma_whitelist array requires an exact match for both Vendor and Device ID. Some hardware vendors support cross bridge peer-to-peer DMA across their entire silicon lineup, so add support for wildcard device IDs to avoid the need to continuously update this array. Signed-off-by: Jacob Moroni <jmoroni@google.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Link: https://patch.msgid.link/20260409150123.3538444-1-jmoroni@google.com 
Currently, the pci_p2pdma_whitelist array requires an exact match for both
Vendor and Device ID. Some hardware vendors support cross bridge
peer-to-peer DMA across their entire silicon lineup, so add support for
wildcard device IDs to avoid the need to continuously update this array.

Signed-off-by: Jacob Moroni <jmoroni@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Link: https://patch.msgid.link/20260409150123.3538444-1-jmoroni@google.com
Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-22T01:09:51+00:00 Linus Torvalds torvalds@linux-foundation.org 2026-02-22T00:37:42+00:00 bf4afc53b77aeaa48b5409da5c8da6bb4eff7f43 This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21T09:02:28+00:00 Kees Cook kees@kernel.org 2026-02-21T07:49:23+00:00 69050f8d6d075dc01af7a5f2f550a8067510366f This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org> 
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
PCI/P2PDMA: Reset page reference count when page mapping fails 2026-01-14T17:07:06+00:00 Alistair Popple apopple@nvidia.com 2026-01-12T00:54:40+00:00 83014d82a1100abc89f7712ad67c3e5accaddc43 When mapping a p2pdma page the page reference count is initialised to 1 prior to calling vm_insert_page(). This is to avoid vm_insert_page() warning if the page refcount is zero. Prior to setting the page count there is a check to ensure the page is currently free (ie. has a zero reference count). However vm_insert_page() can fail. In this case the pages are freed back to the genalloc pool, but that does not reset the page refcount. So a future allocation of the same page will see the elevated page refcount from the previous set_page_count() call triggering the VM_WARN_ON_ONCE_PAGE checking that the page is free. Fix this by resetting the page refcount to zero using set_page_count(). Note that put_page() is not used because that would result in freeing the page twice due to implicitly calling p2pdma_folio_free(). Fixes: b7e282378773 ("mm/mm_init: move p2pdma page refcount initialisation to p2pdma") Signed-off-by: Alistair Popple <apopple@nvidia.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Balbir Singh <balbirs@nvidia.com> Link: https://patch.msgid.link/20260112005440.998543-1-apopple@nvidia.com 
When mapping a p2pdma page the page reference count is initialised to 1
prior to calling vm_insert_page(). This is to avoid vm_insert_page()
warning if the page refcount is zero. Prior to setting the page count there
is a check to ensure the page is currently free (ie. has a zero reference
count).

However vm_insert_page() can fail. In this case the pages are freed back to
the genalloc pool, but that does not reset the page refcount.  So a future
allocation of the same page will see the elevated page refcount from the
previous set_page_count() call triggering the VM_WARN_ON_ONCE_PAGE checking
that the page is free.

Fix this by resetting the page refcount to zero using set_page_count().
Note that put_page() is not used because that would result in freeing the
page twice due to implicitly calling p2pdma_folio_free().

Fixes: b7e282378773 ("mm/mm_init: move p2pdma page refcount initialisation to p2pdma")
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Balbir Singh <balbirs@nvidia.com>
Link: https://patch.msgid.link/20260112005440.998543-1-apopple@nvidia.com
PCI/P2PDMA: Fix p2pmem_alloc_mmap() warning condition 2026-01-08T15:56:20+00:00 Hou Tao houtao1@huawei.com 2025-12-20T04:04:35+00:00 cb500023a75246f60b79af9f7321d6e75330c5b5 Commit b7e282378773 has already changed the initial page refcount of p2pdma page from one to zero, however, in p2pmem_alloc_mmap() it uses "VM_WARN_ON_ONCE_PAGE(!page_ref_count(page))" to assert the initial page refcount should not be zero and the following will be reported when CONFIG_DEBUG_VM is enabled: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x380400000 flags: 0x20000000002000(reserved|node=0|zone=4) raw: 0020000000002000 ff1100015e3ab440 0000000000000000 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: VM_WARN_ON_ONCE_PAGE(!page_ref_count(page)) ------------[ cut here ]------------ WARNING: CPU: 5 PID: 449 at drivers/pci/p2pdma.c:240 p2pmem_alloc_mmap+0x83a/0xa60 Fix by using "page_ref_count(page)" as the assertion condition. Fixes: b7e282378773 ("mm/mm_init: move p2pdma page refcount initialisation to p2pdma") Signed-off-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Alistair Popple <apopple@nvidia.com> Link: https://patch.msgid.link/20251220040446.274991-3-houtao@huaweicloud.com 
Commit b7e282378773 has already changed the initial page refcount of
p2pdma page from one to zero, however, in p2pmem_alloc_mmap() it uses
"VM_WARN_ON_ONCE_PAGE(!page_ref_count(page))" to assert the initial page
refcount should not be zero and the following will be reported when
CONFIG_DEBUG_VM is enabled:

  page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x380400000
  flags: 0x20000000002000(reserved|node=0|zone=4)
  raw: 0020000000002000 ff1100015e3ab440 0000000000000000 0000000000000000
  raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
  page dumped because: VM_WARN_ON_ONCE_PAGE(!page_ref_count(page))
  ------------[ cut here ]------------
  WARNING: CPU: 5 PID: 449 at drivers/pci/p2pdma.c:240 p2pmem_alloc_mmap+0x83a/0xa60

Fix by using "page_ref_count(page)" as the assertion condition.

Fixes: b7e282378773 ("mm/mm_init: move p2pdma page refcount initialisation to p2pdma")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Link: https://patch.msgid.link/20251220040446.274991-3-houtao@huaweicloud.com
PCI/P2PDMA: Release per-CPU pgmap ref when vm_insert_page() fails 2026-01-08T15:27:50+00:00 Hou Tao houtao1@huawei.com 2025-12-20T04:04:34+00:00 6220694c52a5a04102b48109e4f24e958b559bd3 When vm_insert_page() fails in p2pmem_alloc_mmap(), p2pmem_alloc_mmap() doesn't invoke percpu_ref_put() to free the per-CPU ref of pgmap acquired after gen_pool_alloc_owner(), and memunmap_pages() will hang forever when trying to remove the PCI device. Fix it by adding the missed percpu_ref_put(). Fixes: 7e9c7ef83d78 ("PCI/P2PDMA: Allow userspace VMA allocations through sysfs") Signed-off-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Alistair Popple <apopple@nvidia.com> Link: https://patch.msgid.link/20251220040446.274991-2-houtao@huaweicloud.com 
When vm_insert_page() fails in p2pmem_alloc_mmap(), p2pmem_alloc_mmap()
doesn't invoke percpu_ref_put() to free the per-CPU ref of pgmap acquired
after gen_pool_alloc_owner(), and memunmap_pages() will hang forever when
trying to remove the PCI device.

Fix it by adding the missed percpu_ref_put().

Fixes: 7e9c7ef83d78 ("PCI/P2PDMA: Allow userspace VMA allocations through sysfs")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Link: https://patch.msgid.link/20251220040446.274991-2-houtao@huaweicloud.com
Merge tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 2025-12-05T21:52:43+00:00 Linus Torvalds torvalds@linux-foundation.org 2025-12-05T21:52:43+00:00 7203ca412fc8e8a0588e9adc0f777d3163f8dff3 Pull MM updates from Andrew Morton: "__vmalloc()/kvmalloc() and no-block support" (Uladzislau Rezki) Rework the vmalloc() code to support non-blocking allocations (GFP_ATOIC, GFP_NOWAIT) "ksm: fix exec/fork inheritance" (xu xin) Fix a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not inherited across fork/exec "mm/zswap: misc cleanup of code and documentations" (SeongJae Park) Some light maintenance work on the zswap code "mm/page_owner: add debugfs files 'show_handles' and 'show_stacks_handles'" (Mauricio Faria de Oliveira) Enhance the /sys/kernel/debug/page_owner debug feature by adding unique identifiers to differentiate the various stack traces so that userspace monitoring tools can better match stack traces over time "mm/page_alloc: pcp->batch cleanups" (Joshua Hahn) Minor alterations to the page allocator's per-cpu-pages feature "Improve UFFDIO_MOVE scalability by removing anon_vma lock" (Lokesh Gidra) Address a scalability issue in userfaultfd's UFFDIO_MOVE operation "kasan: cleanups for kasan_enabled() checks" (Sabyrzhan Tasbolatov) "drivers/base/node: fold node register and unregister functions" (Donet Tom) Clean up the NUMA node handling code a little "mm: some optimizations for prot numa" (Kefeng Wang) Cleanups and small optimizations to the NUMA allocation hinting code "mm/page_alloc: Batch callers of free_pcppages_bulk" (Joshua Hahn) Address long lock hold times at boot on large machines. These were causing (harmless) softlockup warnings "optimize the logic for handling dirty file folios during reclaim" (Baolin Wang) Remove some now-unnecessary work from page reclaim "mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage" (SeongJae Park) Enhance the DAMOS auto-tuning feature "mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM" (Quanmin Yan) Fix DAMON_LRU_SORT and DAMON_RECLAIM with certain userspace configuration "expand mmap_prepare functionality, port more users" (Lorenzo Stoakes) Enhance the new(ish) file_operations.mmap_prepare() method and port additional callsites from the old ->mmap() over to ->mmap_prepare() "Fix stale IOTLB entries for kernel address space" (Lu Baolu) Fix a bug (and possible security issue on non-x86) in the IOMMU code. In some situations the IOMMU could be left hanging onto a stale kernel pagetable entry "mm/huge_memory: cleanup __split_unmapped_folio()" (Wei Yang) Clean up and optimize the folio splitting code "mm, swap: misc cleanup and bugfix" (Kairui Song) Some cleanups and a minor fix in the swap discard code "mm/damon: misc documentation fixups" (SeongJae Park) "mm/damon: support pin-point targets removal" (SeongJae Park) Permit userspace to remove a specific monitoring target in the middle of the current targets list "mm: MISC follow-up patches for linux/pgalloc.h" (Harry Yoo) A couple of cleanups related to mm header file inclusion "mm/swapfile.c: select swap devices of default priority round robin" (Baoquan He) improve the selection of swap devices for NUMA machines "mm: Convert memory block states (MEM_*) macros to enums" (Israel Batista) Change the memory block labels from macros to enums so they will appear in kernel debug info "ksm: perform a range-walk to jump over holes in break_ksm" (Pedro Demarchi Gomes) Address an inefficiency when KSM unmerges an address range "mm/damon/tests: fix memory bugs in kunit tests" (SeongJae Park) Fix leaks and unhandled malloc() failures in DAMON userspace unit tests "some cleanups for pageout()" (Baolin Wang) Clean up a couple of minor things in the page scanner's writeback-for-eviction code "mm/hugetlb: refactor sysfs/sysctl interfaces" (Hui Zhu) Move hugetlb's sysfs/sysctl handling code into a new file "introduce VM_MAYBE_GUARD and make it sticky" (Lorenzo Stoakes) Make the VMA guard regions available in /proc/pid/smaps and improves the mergeability of guarded VMAs "mm: perform guard region install/remove under VMA lock" (Lorenzo Stoakes) Reduce mmap lock contention for callers performing VMA guard region operations "vma_start_write_killable" (Matthew Wilcox) Start work on permitting applications to be killed when they are waiting on a read_lock on the VMA lock "mm/damon/tests: add more tests for online parameters commit" (SeongJae Park) Add additional userspace testing of DAMON's "commit" feature "mm/damon: misc cleanups" (SeongJae Park) "make VM_SOFTDIRTY a sticky VMA flag" (Lorenzo Stoakes) Address the possible loss of a VMA's VM_SOFTDIRTY flag when that VMA is merged with another "mm: support device-private THP" (Balbir Singh) Introduce support for Transparent Huge Page (THP) migration in zone device-private memory "Optimize folio split in memory failure" (Zi Yan) "mm/huge_memory: Define split_type and consolidate split support checks" (Wei Yang) Some more cleanups in the folio splitting code "mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries" (Lorenzo Stoakes) Clean up our handling of pagetable leaf entries by introducing the concept of 'software leaf entries', of type softleaf_t "reparent the THP split queue" (Muchun Song) Reparent the THP split queue to its parent memcg. This is in preparation for addressing the long-standing "dying memcg" problem, wherein dead memcg's linger for too long, consuming memory resources "unify PMD scan results and remove redundant cleanup" (Wei Yang) A little cleanup in the hugepage collapse code "zram: introduce writeback bio batching" (Sergey Senozhatsky) Improve zram writeback efficiency by introducing batched bio writeback support "memcg: cleanup the memcg stats interfaces" (Shakeel Butt) Clean up our handling of the interrupt safety of some memcg stats "make vmalloc gfp flags usage more apparent" (Vishal Moola) Clean up vmalloc's handling of incoming GFP flags "mm: Add soft-dirty and uffd-wp support for RISC-V" (Chunyan Zhang) Teach soft dirty and userfaultfd write protect tracking to use RISC-V's Svrsw60t59b extension "mm: swap: small fixes and comment cleanups" (Youngjun Park) Fix a small bug and clean up some of the swap code "initial work on making VMA flags a bitmap" (Lorenzo Stoakes) Start work on converting the vma struct's flags to a bitmap, so we stop running out of them, especially on 32-bit "mm/swapfile: fix and cleanup swap list iterations" (Youngjun Park) Address a possible bug in the swap discard code and clean things up a little [ This merge also reverts commit ebb9aeb980e5 ("vfio/nvgrace-gpu: register device memory for poison handling") because it looks broken to me, I've asked for clarification - Linus ] * tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits) mm: fix vma_start_write_killable() signal handling mm/swapfile: use plist_for_each_entry in __folio_throttle_swaprate mm/swapfile: fix list iteration when next node is removed during discard fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling mm/kfence: add reboot notifier to disable KFENCE on shutdown memcg: remove inc/dec_lruvec_kmem_state helpers selftests/mm/uffd: initialize char variable to Null mm: fix DEBUG_RODATA_TEST indentation in Kconfig mm: introduce VMA flags bitmap type tools/testing/vma: eliminate dependency on vma->__vm_flags mm: simplify and rename mm flags function for clarity mm: declare VMA flags by bit zram: fix a spelling mistake mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity mm/vmscan: skip increasing kswapd_failures when reclaim was boosted pagemap: update BUDDY flag documentation mm: swap: remove scan_swap_map_slots() references from comments mm: swap: change swap_alloc_slow() to void mm, swap: remove redundant comment for read_swap_cache_async mm, swap: use SWP_SOLIDSTATE to determine if swap is rotational ... 
Pull MM updates from Andrew Morton:

  "__vmalloc()/kvmalloc() and no-block support" (Uladzislau Rezki)
     Rework the vmalloc() code to support non-blocking allocations
     (GFP_ATOIC, GFP_NOWAIT)

  "ksm: fix exec/fork inheritance" (xu xin)
     Fix a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not
     inherited across fork/exec

  "mm/zswap: misc cleanup of code and documentations" (SeongJae Park)
     Some light maintenance work on the zswap code

  "mm/page_owner: add debugfs files 'show_handles' and 'show_stacks_handles'" (Mauricio Faria de Oliveira)
     Enhance the /sys/kernel/debug/page_owner debug feature by adding
     unique identifiers to differentiate the various stack traces so
     that userspace monitoring tools can better match stack traces over
     time

  "mm/page_alloc: pcp->batch cleanups" (Joshua Hahn)
     Minor alterations to the page allocator's per-cpu-pages feature

  "Improve UFFDIO_MOVE scalability by removing anon_vma lock" (Lokesh Gidra)
     Address a scalability issue in userfaultfd's UFFDIO_MOVE operation

  "kasan: cleanups for kasan_enabled() checks" (Sabyrzhan Tasbolatov)

  "drivers/base/node: fold node register and unregister functions" (Donet Tom)
     Clean up the NUMA node handling code a little

  "mm: some optimizations for prot numa" (Kefeng Wang)
     Cleanups and small optimizations to the NUMA allocation hinting
     code

  "mm/page_alloc: Batch callers of free_pcppages_bulk" (Joshua Hahn)
     Address long lock hold times at boot on large machines. These were
     causing (harmless) softlockup warnings

  "optimize the logic for handling dirty file folios during reclaim" (Baolin Wang)
     Remove some now-unnecessary work from page reclaim

  "mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage" (SeongJae Park)
     Enhance the DAMOS auto-tuning feature

  "mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM" (Quanmin Yan)
     Fix DAMON_LRU_SORT and DAMON_RECLAIM with certain userspace
     configuration

  "expand mmap_prepare functionality, port more users" (Lorenzo Stoakes)
     Enhance the new(ish) file_operations.mmap_prepare() method and port
     additional callsites from the old ->mmap() over to ->mmap_prepare()

  "Fix stale IOTLB entries for kernel address space" (Lu Baolu)
     Fix a bug (and possible security issue on non-x86) in the IOMMU
     code. In some situations the IOMMU could be left hanging onto a
     stale kernel pagetable entry

  "mm/huge_memory: cleanup __split_unmapped_folio()" (Wei Yang)
     Clean up and optimize the folio splitting code

  "mm, swap: misc cleanup and bugfix" (Kairui Song)
     Some cleanups and a minor fix in the swap discard code

  "mm/damon: misc documentation fixups" (SeongJae Park)

  "mm/damon: support pin-point targets removal" (SeongJae Park)
     Permit userspace to remove a specific monitoring target in the
     middle of the current targets list

  "mm: MISC follow-up patches for linux/pgalloc.h" (Harry Yoo)
     A couple of cleanups related to mm header file inclusion

  "mm/swapfile.c: select swap devices of default priority round robin" (Baoquan He)
     improve the selection of swap devices for NUMA machines

  "mm: Convert memory block states (MEM_*) macros to enums" (Israel Batista)
     Change the memory block labels from macros to enums so they will
     appear in kernel debug info

  "ksm: perform a range-walk to jump over holes in break_ksm" (Pedro Demarchi Gomes)
     Address an inefficiency when KSM unmerges an address range

  "mm/damon/tests: fix memory bugs in kunit tests" (SeongJae Park)
     Fix leaks and unhandled malloc() failures in DAMON userspace unit
     tests

  "some cleanups for pageout()" (Baolin Wang)
     Clean up a couple of minor things in the page scanner's
     writeback-for-eviction code

  "mm/hugetlb: refactor sysfs/sysctl interfaces" (Hui Zhu)
     Move hugetlb's sysfs/sysctl handling code into a new file

  "introduce VM_MAYBE_GUARD and make it sticky" (Lorenzo Stoakes)
     Make the VMA guard regions available in /proc/pid/smaps and
     improves the mergeability of guarded VMAs

  "mm: perform guard region install/remove under VMA lock" (Lorenzo Stoakes)
     Reduce mmap lock contention for callers performing VMA guard region
     operations

  "vma_start_write_killable" (Matthew Wilcox)
     Start work on permitting applications to be killed when they are
     waiting on a read_lock on the VMA lock

  "mm/damon/tests: add more tests for online parameters commit" (SeongJae Park)
     Add additional userspace testing of DAMON's "commit" feature

  "mm/damon: misc cleanups" (SeongJae Park)

  "make VM_SOFTDIRTY a sticky VMA flag" (Lorenzo Stoakes)
     Address the possible loss of a VMA's VM_SOFTDIRTY flag when that
     VMA is merged with another

  "mm: support device-private THP" (Balbir Singh)
     Introduce support for Transparent Huge Page (THP) migration in zone
     device-private memory

  "Optimize folio split in memory failure" (Zi Yan)

  "mm/huge_memory: Define split_type and consolidate split support checks" (Wei Yang)
     Some more cleanups in the folio splitting code

  "mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries" (Lorenzo Stoakes)
     Clean up our handling of pagetable leaf entries by introducing the
     concept of 'software leaf entries', of type softleaf_t

  "reparent the THP split queue" (Muchun Song)
     Reparent the THP split queue to its parent memcg. This is in
     preparation for addressing the long-standing "dying memcg" problem,
     wherein dead memcg's linger for too long, consuming memory
     resources

  "unify PMD scan results and remove redundant cleanup" (Wei Yang)
     A little cleanup in the hugepage collapse code

  "zram: introduce writeback bio batching" (Sergey Senozhatsky)
     Improve zram writeback efficiency by introducing batched bio
     writeback support

  "memcg: cleanup the memcg stats interfaces" (Shakeel Butt)
     Clean up our handling of the interrupt safety of some memcg stats

  "make vmalloc gfp flags usage more apparent" (Vishal Moola)
     Clean up vmalloc's handling of incoming GFP flags

  "mm: Add soft-dirty and uffd-wp support for RISC-V" (Chunyan Zhang)
     Teach soft dirty and userfaultfd write protect tracking to use
     RISC-V's Svrsw60t59b extension

  "mm: swap: small fixes and comment cleanups" (Youngjun Park)
     Fix a small bug and clean up some of the swap code

  "initial work on making VMA flags a bitmap" (Lorenzo Stoakes)
     Start work on converting the vma struct's flags to a bitmap, so we
     stop running out of them, especially on 32-bit

  "mm/swapfile: fix and cleanup swap list iterations" (Youngjun Park)
     Address a possible bug in the swap discard code and clean things
     up a little

[ This merge also reverts commit ebb9aeb980e5 ("vfio/nvgrace-gpu:
  register device memory for poison handling") because it looks
  broken to me, I've asked for clarification   - Linus ]

* tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
  mm: fix vma_start_write_killable() signal handling
  mm/swapfile: use plist_for_each_entry in __folio_throttle_swaprate
  mm/swapfile: fix list iteration when next node is removed during discard
  fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling
  mm/kfence: add reboot notifier to disable KFENCE on shutdown
  memcg: remove inc/dec_lruvec_kmem_state helpers
  selftests/mm/uffd: initialize char variable to Null
  mm: fix DEBUG_RODATA_TEST indentation in Kconfig
  mm: introduce VMA flags bitmap type
  tools/testing/vma: eliminate dependency on vma->__vm_flags
  mm: simplify and rename mm flags function for clarity
  mm: declare VMA flags by bit
  zram: fix a spelling mistake
  mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity
  mm/vmscan: skip increasing kswapd_failures when reclaim was boosted
  pagemap: update BUDDY flag documentation
  mm: swap: remove scan_swap_map_slots() references from comments
  mm: swap: change swap_alloc_slow() to void
  mm, swap: remove redundant comment for read_swap_cache_async
  mm, swap: use SWP_SOLIDSTATE to determine if swap is rotational
  ...