kernel/linux.git/mm/internal.h, branch v7.1-rc5

Merge tag 'mm-hotfixes-stable-2026-04-19-00-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-04-19T21:45:37+00:00

Pull MM fixes from Andrew Morton: "7 hotfixes. 6 are cc:stable and all are for MM. Please see the individual changelogs for details" * tag 'mm-hotfixes-stable-2026-04-19-00-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: mm/damon/core: disallow non-power of two min_region_sz on damon_start() mm/vmalloc: take vmap_purge_lock in shrinker mm: call ->free_folio() directly in folio_unmap_invalidate() mm: blk-cgroup: fix use-after-free in cgwb_release_workfn() mm/zone_device: do not touch device folio after calling ->folio_free() mm/damon/core: disallow time-quota setting zero esz mm/mempolicy: fix weighted interleave auto sysfs name

mm: call ->free_folio() directly in folio_unmap_invalidate()

2026-04-19T06:24:27+00:00

We can only call filemap_free_folio() if we have a reference to (or hold a lock on) the mapping. Otherwise, we've already removed the folio from the mapping so it no longer pins the mapping and the mapping can be removed, causing a use-after-free when accessing mapping->a_ops. Follow the same pattern as __remove_mapping() and load the free_folio function pointer before dropping the lock on the mapping. That lets us make filemap_free_folio() static as this was the only caller outside filemap.c. Link: https://lore.kernel.org/20260413184314.3419945-1-willy@infradead.org Fixes: fb7d3bc41493 ("mm/filemap: drop streaming/uncached pages when writeback completes") Signed-off-by: Matthew Wilcox (Oracle) Reported-by: Google Big Sleep Cc: Jens Axboe Cc: Jan Kara Cc: Signed-off-by: Andrew Morton

Merge tag 'memblock-v7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock

2026-04-18T18:29:14+00:00

Pull memblock updates from Mike Rapoport: - improve debuggability of reserve_mem kernel parameter handling with print outs in case of a failure and debugfs info showing what was actually reserved - Make memblock_free_late() and free_reserved_area() use the same core logic for freeing the memory to buddy and ensure it takes care of updating memblock arrays when ARCH_KEEP_MEMBLOCK is enabled. * tag 'memblock-v7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock: x86/alternative: delay freeing of smp_locks section memblock: warn when freeing reserved memory before memory map is initialized memblock, treewide: make memblock_free() handle late freeing memblock: make free_reserved_area() update memblock if ARCH_KEEP_MEMBLOCK=y memblock: extract page freeing from free_reserved_area() into a helper memblock: make free_reserved_area() more robust mm: move free_reserved_area() to mm/memblock.c powerpc: opal-core: pair alloc_pages_exact() with free_pages_exact() powerpc: fadump: pair alloc_pages_exact() with free_pages_exact() memblock: reserve_mem: fix end caclulation in reserve_mem_release_by_name() memblock: move reserve_bootmem_range() to memblock.c and make it static memblock: Add reserve_mem debugfs info memblock: Print out errors on reserve_mem parser

mm: add mmap_action_simple_ioremap()

2026-04-05T20:53:43+00:00

Currently drivers use vm_iomap_memory() as a simple helper function for I/O remapping memory over a range starting at a specified physical address over a specified length. In order to utilise this from mmap_prepare, separate out the core logic into __simple_ioremap_prep(), update vm_iomap_memory() to use it, and add simple_ioremap_prepare() to do the same with a VMA descriptor object. We also add MMAP_SIMPLE_IO_REMAP and relevant fields to the struct mmap_action type to permit this operation also. We use mmap_action_ioremap() to set up the actual I/O remap operation once we have checked and figured out the parameters, which makes simple_ioremap_prepare() easy to implement. We then add mmap_action_simple_ioremap() to allow drivers to make use of this mode. We update the mmap_prepare documentation to describe this mode. Finally, we update the VMA tests to reflect this change. Link: https://lkml.kernel.org/r/a08ef1c4542202684da63bb37f459d5dbbeddd91.1774045440.git.ljs@kernel.org Signed-off-by: Lorenzo Stoakes (Oracle) Reviewed-by: Suren Baghdasaryan Acked-by: Vlastimil Babka (SUSE) Cc: Alexander Shishkin Cc: Alexandre Torgue Cc: Al Viro Cc: Arnd Bergmann Cc: Bodo Stroesser Cc: Christian Brauner Cc: Clemens Ladisch Cc: David Hildenbrand Cc: David Howells Cc: Dexuan Cui Cc: Greg Kroah-Hartman Cc: Haiyang Zhang Cc: Jan Kara Cc: Jann Horn Cc: Jonathan Corbet Cc: K. Y. Srinivasan Cc: Liam Howlett Cc: Long Li Cc: Marc Dionne Cc: "Martin K. Petersen" Cc: Maxime Coquelin Cc: Michal Hocko Cc: Mike Rapoport Cc: Miquel Raynal Cc: Pedro Falcato Cc: Richard Weinberger Cc: Ryan Roberts Cc: Vignesh Raghavendra Cc: Wei Liu Signed-off-by: Andrew Morton

mm: have mmap_action_complete() handle the rmap lock and unmap

2026-04-05T20:53:42+00:00

Rather than have the callers handle this both the rmap lock release and unmapping the VMA on error, handle it within the mmap_action_complete() logic where it makes sense to, being careful not to unlock twice. This simplifies the logic and makes it harder to make mistake with this, while retaining correct behaviour with regard to avoiding deadlocks. Also replace the call_action_complete() function with a direct invocation of mmap_action_complete() as the abstraction is no longer required. Also update the VMA tests to reflect this change. Link: https://lkml.kernel.org/r/8d1ee8ebd3542d006a47e8382fb80cf5b57ecf10.1774045440.git.ljs@kernel.org Signed-off-by: Lorenzo Stoakes (Oracle) Acked-by: Vlastimil Babka (SUSE) Cc: Alexander Shishkin Cc: Alexandre Torgue Cc: Al Viro Cc: Arnd Bergmann Cc: Bodo Stroesser Cc: Christian Brauner Cc: Clemens Ladisch Cc: David Hildenbrand Cc: David Howells Cc: Dexuan Cui Cc: Greg Kroah-Hartman Cc: Haiyang Zhang Cc: Jan Kara Cc: Jann Horn Cc: Jonathan Corbet Cc: K. Y. Srinivasan Cc: Liam Howlett Cc: Long Li Cc: Marc Dionne Cc: "Martin K. Petersen" Cc: Maxime Coquelin Cc: Michal Hocko Cc: Mike Rapoport Cc: Miquel Raynal Cc: Pedro Falcato Cc: Richard Weinberger Cc: Ryan Roberts Cc: Suren Baghdasaryan Cc: Vignesh Raghavendra Cc: Wei Liu Signed-off-by: Andrew Morton

mm: various small mmap_prepare cleanups

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

Patch series "mm: expand mmap_prepare functionality and usage", v4. This series expands the mmap_prepare functionality, which is intended to replace the deprecated f_op->mmap hook which has been the source of bugs and security issues for some time. This series starts with some cleanup of existing mmap_prepare logic, then adds documentation for the mmap_prepare call to make it easier for filesystem and driver writers to understand how it works. It then importantly adds a vm_ops->mapped hook, a key feature that was missing from mmap_prepare previously - this is invoked when a driver which specifies mmap_prepare has successfully been mapped but not merged with another VMA. mmap_prepare is invoked prior to a merge being attempted, so you cannot manipulate state such as reference counts as if it were a new mapping. The vm_ops->mapped hook allows a driver to perform tasks required at this stage, and provides symmetry against subsequent vm_ops->open,close calls. The series uses this to correct the afs implementation which wrongly manipulated reference count at mmap_prepare time. It then adds an mmap_prepare equivalent of vm_iomap_memory() - mmap_action_simple_ioremap(), then uses this to update a number of drivers. It then splits out the mmap_prepare compatibility layer (which allows for invocation of mmap_prepare hooks in an mmap() hook) in such a way as to allow for more incremental implementation of mmap_prepare hooks. It then uses this to extend mmap_prepare usage in drivers. Finally it adds an mmap_prepare equivalent of vm_map_pages(), which lays the foundation for future work which will extend mmap_prepare to DMA coherent mappings. This patch (of 21): Rather than passing arbitrary fields, pass a vm_area_desc pointer to mmap prepare functions to mmap prepare, and an action and vma pointer to mmap complete in order to put all the action-specific logic in the function actually doing the work. Additionally, allow mmap prepare functions to return an error so we can error out as soon as possible if there is something logically incorrect in the input. Update remap_pfn_range_prepare() to properly check the input range for the CoW case. Also remove io_remap_pfn_range_complete(), as we can simply set up the fields correctly in io_remap_pfn_range_prepare() and use remap_pfn_range_complete() for this. While we're here, make remap_pfn_range_prepare_vma() a little neater, and pass mmap_action directly to call_action_complete(). Then, update compat_vma_mmap() to perform its logic directly, as __compat_vma_map() is not used by anything so we don't need to export it. Also update compat_vma_mmap() to use vfs_mmap_prepare() rather than calling the mmap_prepare op directly. Finally, update the VMA userland tests to reflect the changes. Link: https://lkml.kernel.org/r/cover.1774045440.git.ljs@kernel.org Link: https://lkml.kernel.org/r/99f408e4694f44ab12bdc55fe0bd9685d3bd1117.1774045440.git.ljs@kernel.org Signed-off-by: Lorenzo Stoakes (Oracle) Acked-by: Vlastimil Babka (SUSE) Cc: Alexander Shishkin Cc: Alexandre Torgue Cc: Al Viro Cc: Arnd Bergmann Cc: Bodo Stroesser Cc: Christian Brauner Cc: Clemens Ladisch Cc: David Hildenbrand Cc: David Howells Cc: Dexuan Cui Cc: Greg Kroah-Hartman Cc: Haiyang Zhang Cc: Jan Kara Cc: Jann Horn Cc: Jonathan Corbet Cc: K. Y. Srinivasan Cc: Liam Howlett Cc: Long Li Cc: Marc Dionne Cc: "Martin K. Petersen" Cc: Maxime Coquelin Cc: Michal Hocko Cc: Mike Rapoport Cc: Miquel Raynal Cc: Pedro Falcato Cc: Richard Weinberger Cc: Ryan Roberts Cc: Suren Baghdasaryan Cc: Vignesh Raghavendra Cc: Wei Liu Signed-off-by: Andrew Morton

mm: update vma_supports_mlock() to use new VMA flags

2026-04-05T20:53:40+00:00

We now have the ability to test all of this using the new vma_flags_t approach, so let's do so. Link: https://lkml.kernel.org/r/49cc166dbafe0a81abc4581a9f5c84630b02fcb8.1774034900.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: convert do_brk_flags() to use vma_flags_t

2026-04-05T20:53:40+00:00

In order to be able to do this, we need to change VM_DATA_DEFAULT_FLAGS and friends and update the architecture-specific definitions also. We then have to update some KSM logic to handle VMA flags, and introduce VMA_STACK_FLAGS to define the vma_flags_t equivalent of VM_STACK_FLAGS. We also introduce two helper functions for use during the time we are converting legacy flags to vma_flags_t values - vma_flags_to_legacy() and legacy_to_vma_flags(). This enables us to iteratively make changes to break these changes up into separate parts. We use these explicitly here to keep VM_STACK_FLAGS around for certain users which need to maintain the legacy vm_flags_t values for the time being. We are no longer able to rely on the simple VM_xxx being set to zero if the feature is not enabled, so in the case of VM_DROPPABLE we introduce VMA_DROPPABLE as the vma_flags_t equivalent, which is set to EMPTY_VMA_FLAGS if the droppable flag is not available. While we're here, we make the description of do_brk_flags() into a kdoc comment, as it almost was already. We use vma_flags_to_legacy() to not need to update the vm_get_page_prot() logic as this time. Note that in create_init_stack_vma() we have to replace the BUILD_BUG_ON() with a VM_WARN_ON_ONCE() as the tested values are no longer build time available. We also update mprotect_fixup() to use VMA flags where possible, though we have to live with a little duplication between vm_flags_t and vma_flags_t values for the time being until further conversions are made. While we're here, update VM_SPECIAL to be defined in terms of VMA_SPECIAL_FLAGS now we have vma_flags_to_legacy(). Finally, we update the VMA tests to reflect these changes. Link: https://lkml.kernel.org/r/d02e3e45d9a33d7904b149f5604904089fd640ae.1774034900.git.ljs@kernel.org Signed-off-by: Lorenzo Stoakes (Oracle) Acked-by: Paul Moore [SELinux] 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: 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: change to return bool for the MMU notifier's young flag check

2026-04-05T20:53:35+00:00

The MMU notifier young flag check related functions only return whether the young flag was set. Change the return type to bool to make the intention clearer. Link: https://lkml.kernel.org/r/a9ad3fe938002d87358e7bfca264f753ab602561.1774075004.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang Reviewed-by: Lorenzo Stoakes (Oracle) Acked-by: David Hildenbrand (Arm) Cc: Liam Howlett Cc: Michal Hocko Cc: Mike Rapoport Cc: Ritesh Harjani (IBM) Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton

mm/sparse: move memory hotplug bits to sparse-vmemmap.c

2026-04-05T20:53:33+00:00

Let's move all memory hoptplug related code to sparse-vmemmap.c. We only have to expose sparse_index_init(). While at it, drop the definition of sparse_index_init() for !CONFIG_SPARSEMEM, which is unused, and place the declaration in internal.h. Link: https://lkml.kernel.org/r/20260320-sparsemem_cleanups-v2-15-096addc8800d@kernel.org Signed-off-by: David Hildenbrand (Arm) Reviewed-by: Lorenzo Stoakes (Oracle) Reviewed-by: Mike Rapoport (Microsoft) Cc: Axel Rasmussen Cc: Liam Howlett Cc: Michal Hocko Cc: Oscar Salvador Cc: Sidhartha Kumar Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Wei Xu Cc: Yuanchu Xie Signed-off-by: Andrew Morton