From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5DC99539771 for ; Tue, 13 Oct 2026 18:52:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791917534; cv=none; b=LmoLSV7G/raclZfAbrEFajipQOtx6K78lBhjjvI2ZQEbl12opdxao6EAKfjrBmaViKhH7MqVjDr9Celut26mNIBVjeUMpEDvrPMNST+6KhXKkd+++qrDtFeQDlCdHQRjACASaNTy7PaC9sQyOnaWVYE1ICzJbwp7XQIh1HHsKbo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791917534; c=relaxed/simple; bh=3UUiUZuj9E6XhykkjvltiGwTa8DtIbukVIrJGeuHKAA=; h=Date:To:From:Subject:Message-Id; b=Gp+hWtz4Tatd+GCaI9pDhEqtLfeU7zqPbqqXy96SX9v0sD2lx0RljOhXhCN62oIAEKZJpJ75w4sDY7i7dyEEgyxEUqZ/VlVShCtvbl9qewq1yFKxvqPvowi7nZNm2oduFx/toiuGKy636RE+y+A8xdmK707hh/SLdfGzPFdX8bA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=H2BBLGnx; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="H2BBLGnx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 303F21F000FF; Tue, 13 Oct 2026 18:52:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1791917532; bh=jOUN3oLQZUfsbxuYQJR84Mo2vpYZwOCKpu7P1m8ePKs=; h=Date:To:From:Subject; b=H2BBLGnxjAk8hin8kdMZm+RKOGHyf4YyoOSZ4tzOpTLewGpiaybI1IERuJq+VIS19 BZU/GxzfP1mdEmd44/f561hYp1S+0N/UxCkBqZeyTguSFqbVHPeyz9R2hMU394uGq5 R4pB3uQjaKqSOPFnGWvFizRJcJAu/73X/sPF/nz0= Date: Tue, 13 Oct 2026 11:52:11 -0700 To: mm-commits@vger.kernel.org,ljs@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-remove-vma_io_bit-check-in-vma_is_mm_managed.patch added to mm-unstable branch Message-Id: <20261013185212.303F21F000FF@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm: remove VMA_IO_BIT check in vma[_flags]_is_mm_managed() has been added to the -mm mm-unstable branch. Its filename is mm-remove-vma_io_bit-check-in-vma_is_mm_managed.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-remove-vma_io_bit-check-in-vma_is_mm_managed.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: "Lorenzo Stoakes (ARM)" Subject: mm: remove VMA_IO_BIT check in vma[_flags]_is_mm_managed() Date: Tue, 13 Oct 2026 16:05:06 +0100 We have now made it such that every driver which sets VMA_IO_BIT marks it as not mm-managed. However, vma_flags_is_mm_managed() still checks for VMA_IO_BIT and, if set, treats the mapping as not mm-managed. This was previously required to handle drivers which set VMA_IO_BIT but none of the other flags which identify a mapping as not mm-managed. We have now established that a driver which sets VMA_IO_BIT must also set one of those flags, so the VMA_IO_BIT check is redundant. So remove the VMA_IO_BIT check in vma_flags_is_mm_managed() and update mmap_validate_vma_flags() to use vma_flags_is_mm_managed() rather than open-coding the VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT check. This change means that vma[_flags]_can_merge() doesn't check VMA_IO_BIT any longer (which is now redundant) as it calls vma_flags_is_mm_managed(). Now that the predicate means precisely VMA_PFNMAP_BIT or VMA_MIXEDMAP_BIT, also use it at the other sites which open-code that pair, so the intent is stated rather than the flags, with no functional change: zap_special_vma_range() only zaps mappings which are not mm-managed, as drivers use it to tear down ranges they established themselves. The mprotect() arch PFN modification check applies to mappings not managed by core mm, which may map PFNs without struct pages. NUMA balancing skips VM_MIXEDMAP mappings having already excluded VM_IO and VM_PFNMAP mappings via vma_migratable(), so it skips exactly the mappings not managed by core mm - say so. Finally, update the VMA userland merge 'special' flag tests to no longer assert that VMA_IO_BIT prevents merge as VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT now suffices. Link: https://lore.kernel.org/20261013-b4-mmap-prepare-vma-flag-sanify-v6-26-1aa3c9b139f9@kernel.org Signed-off-by: Lorenzo Stoakes (ARM) Signed-off-by: Andrew Morton Acked-by: David Hildenbrand (Arm) Cc: Liam R. Howlett Cc: Vlastimil Babka Cc: Jann Horn Cc: Pedro Falcato Cc: Mike Rapoport Cc: Suren Baghdasaryan Cc: Michal Hocko Cc: Jonathan Corbet Cc: Greg Kroah-Hartman Cc: Dennis Dalessandro Cc: Jason Gunthorpe Cc: Leon Romanovsky Cc: Paul Moore Cc: Stephen Smalley Cc: Jaroslav Kysela Cc: Takashi Iwai Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Andrii Nakryiko Cc: Eduard Zingerman Cc: Kumar Kartikeya Dwivedi Cc: Zi Yan Cc: Baolin Wang Cc: Nico Pache Cc: Ryan Roberts Cc: Dev Jain Cc: Barry Song Cc: Lance Yang Cc: Usama Arif Cc: Kiryl Shutsemau Cc: Doug Gilbert Cc: James Bottomley Cc: Martin K. Petersen Cc: Simona Vetter Cc: Helge Deller Cc: Sebastian Reichel Cc: John Hubbard Cc: Peter Xu Cc: Masami Hiramatsu Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: Arnaldo Carvalho de Melo Cc: Namhyung Kim Cc: Mark Rutland Cc: Rik van Riel Cc: Harry Yoo Cc: Juri Lelli Cc: Vincent Guittot Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: Thomas Zimmermann Cc: David Airlie Cc: Will Deacon Cc: Aneesh Kumar K.V Cc: Nicholas Piggin Cc: Arnd Bergmann Cc: Muchun Song Cc: Oscar Salvador Cc: Matthew Wilcox (Oracle) Cc: Jan Kara Cc: Marc Zyngier Cc: Oliver Upton Cc: Catalin Marinas Cc: Madhavan Srinivasan Cc: Anup Patel Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Albert Ou Cc: Christian Borntraeger Cc: Janosch Frank Cc: Claudio Imbrenda Cc: Alexander Gordeev Cc: Gerald Schaefer Cc: Heiko Carstens Cc: Vasily Gorbik Cc: David S. Miller Cc: Andreas Larsson Cc: Al Viro Cc: Christian Brauner Cc: Matthew Brost Cc: Joshua Hahn Cc: Rakie Kim Cc: Byungchul Park Cc: Gregory Price Cc: Ying Huang Cc: Alistair Popple Cc: Chris Li Cc: Kairui Song Cc: Kemeng Shi Cc: Nhat Pham Cc: Baoquan He Cc: Youngjun Park Cc: Johannes Weiner Cc: Qi Zheng Cc: Shakeel Butt Cc: Axel Rasmussen Cc: Yuanchu Xie Cc: Wei Xu Cc: Chengming Zhou Cc: Michal Hocko Cc: Miklos Szeredi Cc: Xu Xin Cc: Ihor Solodrai Cc: Bert Karwatzki --- include/linux/mm.h | 3 +-- kernel/sched/fair.c | 2 +- mm/memory.c | 7 ++++--- mm/mprotect.c | 3 +-- mm/vma.c | 2 +- tools/testing/vma/include/dup.h | 3 +-- tools/testing/vma/tests/merge.c | 10 ++-------- 7 files changed, 11 insertions(+), 19 deletions(-) --- a/include/linux/mm.h~mm-remove-vma_io_bit-check-in-vma_is_mm_managed +++ a/include/linux/mm.h @@ -1628,8 +1628,7 @@ static inline bool vma_is_shared_maywrit */ static inline bool vma_flags_is_mm_managed(const vma_flags_t *flags) { - return !vma_flags_test_any(flags, VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT, - VMA_IO_BIT); + return !vma_flags_test_any(flags, VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT); } /** --- a/kernel/sched/fair.c~mm-remove-vma_io_bit-check-in-vma_is_mm_managed +++ a/kernel/sched/fair.c @@ -4417,7 +4417,7 @@ retry_pids: for (; vma; vma = vma_next(&vmi)) { if (!vma_migratable(vma) || !vma_policy_mof(vma) || - is_vm_hugetlb_page(vma) || (vma->vm_flags & VM_MIXEDMAP)) { + is_vm_hugetlb_page(vma) || !vma_is_mm_managed(vma)) { trace_sched_skip_vma_numa(mm, vma, NUMAB_SKIP_UNSUITABLE); continue; } --- a/mm/memory.c~mm-remove-vma_io_bit-check-in-vma_is_mm_managed +++ a/mm/memory.c @@ -2354,19 +2354,20 @@ void zap_vma_range(struct vm_area_struct } /** - * zap_special_vma_range - zap all page table entries in a special vma range + * zap_special_vma_range - zap all page table entries in a VMA which is not + * mm-managed * @vma: the vma covering the range to zap * @address: starting address of the range to zap * @size: number of bytes to zap * * This function does nothing when the provided address range is not fully - * contained in @vma, or when the @vma is not VM_PFNMAP or VM_MIXEDMAP. + * contained in @vma, or when @vma is mm-managed. */ void zap_special_vma_range(struct vm_area_struct *vma, unsigned long address, unsigned long size) { if (!range_in_vma(vma, address, address + size) || - !(vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP))) + vma_is_mm_managed(vma)) return; zap_vma_range(vma, address, size); --- a/mm/mprotect.c~mm-remove-vma_io_bit-check-in-vma_is_mm_managed +++ a/mm/mprotect.c @@ -783,8 +783,7 @@ mprotect_fixup(struct vma_iterator *vmi, * uncommon case, so doesn't need to be very optimized. */ if (arch_has_pfn_modify_check() && - vma_flags_test_any(&old_vma_flags, VMA_PFNMAP_BIT, - VMA_MIXEDMAP_BIT) && + !vma_flags_is_mm_managed(&old_vma_flags) && !vma_flags_test_any_mask(&new_vma_flags, VMA_ACCESS_FLAGS)) { pgprot_t new_pgprot = vm_get_page_prot(newflags); --- a/mm/vma.c~mm-remove-vma_io_bit-check-in-vma_is_mm_managed +++ a/mm/vma.c @@ -2809,7 +2809,7 @@ static int mmap_validate_vma_flags(const return -EINVAL; #endif - if (!vma_flags_test_any(flags, VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT)) { + if (vma_flags_is_mm_managed(flags)) { /* mm-managed mappings may not set VMA_IO_BIT. */ if (WARN_ON_ONCE(vma_flags_test(flags, VMA_IO_BIT))) return -EINVAL; --- a/tools/testing/vma/include/dup.h~mm-remove-vma_io_bit-check-in-vma_is_mm_managed +++ a/tools/testing/vma/include/dup.h @@ -1667,8 +1667,7 @@ static inline bool file_is_dev_zero(cons static inline bool vma_flags_is_mm_managed(const vma_flags_t *flags) { - return !vma_flags_test_any(flags, VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT, - VMA_IO_BIT); + return !vma_flags_test_any(flags, VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT); } static inline bool vma_is_mm_managed(const struct vm_area_struct *vma) --- a/tools/testing/vma/tests/merge.c~mm-remove-vma_io_bit-check-in-vma_is_mm_managed +++ a/tools/testing/vma/tests/merge.c @@ -496,17 +496,11 @@ static bool test_vma_merge_special_flags .mm = &mm, .vmi = &vmi, }; - vma_flag_t special_flags[] = { VMA_IO_BIT, VMA_DONTEXPAND_BIT, + vma_flag_t special_flags[] = { VMA_DONTEXPAND_BIT, VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT }; - vma_flags_t all_special_flags = EMPTY_VMA_FLAGS; int i; struct vm_area_struct *vma_left, *vma; - /* Make sure there aren't new VM_SPECIAL flags. */ - for (i = 0; i < ARRAY_SIZE(special_flags); i++) - vma_flags_set(&all_special_flags, special_flags[i]); - ASSERT_FLAGS_SAME_MASK(&all_special_flags, VMA_SPECIAL_FLAGS); - /* * 01234 * AAA @@ -520,7 +514,7 @@ static bool test_vma_merge_special_flags * 01234 * AAA* * - * This should merge if not for the VM_SPECIAL flag. + * This should merge if not for the 'special' flag. */ vmg_set_range(&vmg, 0x3000, 0x4000, 3, vma_flags); for (i = 0; i < ARRAY_SIZE(special_flags); i++) { _ Patches currently in -mm which might be from ljs@kernel.org are mm-vma-fix-mmap_prepare-file-handling-remove-file_doesnt_need_get.patch mm-vma-introduce-and-use-vma_can_merge.patch mm-consistently-validate-vma-state-after-mmap-hooks.patch mm-vma-ensure-mmap_prepare-doesnt-set-actions-on-a-mergeable-vma.patch mm-make-map_kernel_pages_-internal-and-unexported.patch mm-vma-tidy-up-map-kernel-pages-enum-values.patch mm-assert-mmap-lock-held-use-new-flags-api-in-vm_insert_page.patch mm-add-mmap-action-for-discontiguous-kernel-page-mapping.patch docs-filesystems-update-mmap_prepare-docs-for-discontig-kernel-pgs.patch drivers-usb-mon-update-to-use-mmap_prepare-map-kernel-pages.patch infiniband-update-hfi1-to-use-remap_vmalloc_range.patch selinux-reject-writable-opens-of-policy-file-drop-mmap-shared-write-check.patch alsa-pcm-use-vm_insert_page-to-map-pcm-status-page.patch bpf-arena-mark-arena_map_mmap-mappings-vm_mixedmap.patch mm-vma-add-vma_is_mm_managed-predicates.patch mm-vma-only-allow-mmap-to-clear-vma_maywrite_bit-if-not-mm-managed.patch mm-vma-add-and-use-vma__is_fixed_mapping.patch scsi-sg-convert-mmap-hook-to-mmap_prepare-and-rework.patch fbdev-defio-assert-fbinfo_virtfb-drop-vm_io-add-vm_mixedmap.patch hsi-cmt_speech-convert-mmap-hook-to-mmap_prepare-refactor.patch mm-gup-error-out-early-on-vma_mayread_bit-vmas.patch uprobes-remove-vm_io-set-vm_mixedmap-for-mapped-kernel-pages.patch mm-mlock-clear-vma_locked_mask-over-mmap-callback.patch mm-mlock-eliminate-weird-vma_io_bit-abuse-and-simplify.patch mm-vma-enforce-that-mm-managed-mappings-may-not-set-vma_io_bit.patch mm-remove-vma_io_bit-check-in-vma_is_mm_managed.patch mm-remove-hugetlb_inlineh.patch mm-rename-is_vm_hugetlb_page-to-vma_is_hugetlb.patch mm-drop-some-redundant-checks-around-hugetlb-vmas.patch mm-vma-introduce-vma_is_mm_backed.patch mm-madvise-update-is_valid_guard_vma-to-use-vma_is_mm_backed.patch mm-uffd-use-predicates-for-userfaultfd-checks.patch mm-madvise-use-predicates-for-madvise-madv_dofork.patch mm-eliminate-vma_special_flags-usage-when-hugetlb-explicitly-tested.patch mm-eliminate-vma_special_flags-check-in-lru_gen_look_around.patch mm-avoid-use-of-vma_special_flags-in-migrate_vma_setup.patch mm-eliminate-vm_special-vma_special_flags.patch fuse-dax-do-not-set-vm_mixedmap.patch mm-huge_memory-remove-vma_is_special_huge.patch mm-vma-const-ify-vma_assert_stabilised-and-associated-functions.patch mm-implement-and-use-vma_has_anon_rmap-silence-kcsan.patch mm-update-comments-to-refer-to-anon-rmap-rather-than-anon_vma.patch mm-vma-dont-remove-vma-from-rmap-if-pgoff-unchanged.patch