kernel/linux.git/include/linux/pgtable.h, branch v7.3-rc1

mm: decouple protnone helpers from CONFIG_NUMA_BALANCING

2026-08-05T02:18:36+00:00

Patch series "userfaultfd: working set tracking for VM guest memory", v10. This series adds userfaultfd support for tracking the working set of VM guest memory, so a VMM can identify hot pages and reclaim cold ones to tiered or remote storage. This patch (of 15): pte_protnone() and pmd_protnone() detect present-but-inaccessible page table entries. This capability is useful beyond NUMA balancing -- for example, userfaultfd working set tracking uses protnone PTEs to track page access without unmapping pages. Introduce CONFIG_ARCH_HAS_PTE_PROTNONE to decouple the protnone PTE infrastructure from CONFIG_NUMA_BALANCING. The six architectures that support protnone PTEs (x86_64, arm64, powerpc, s390, riscv, loongarch) now select this option, and CONFIG_NUMA_BALANCING depends on it. No functional change -- the same set of architectures continues to have working protnone support, but the infrastructure is now available independently of NUMA balancing. Link: https://lore.kernel.org/20260708111417.173443-1-kirill@shutemov.name Link: https://lore.kernel.org/20260708111417.173443-2-kirill@shutemov.name Signed-off-by: Kiryl Shutsemau (Meta) Assisted-by: Claude:claude-opus-4-6 Acked-by: SeongJae Park Acked-by: Mike Rapoport (Microsoft) Cc: Andrea Arcangeli Cc: David Hildenbrand Cc: James Houghton Cc: Jonathan Corbet Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Paolo Bonzini Cc: Peter Xu Cc: Sean Christopherson Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Zi Yan Signed-off-by: Andrew Morton

mm: rename ARCH_ENABLE_THP_MIGRATION to ARCH_HAS_PMD_SOFTLEAVES

2026-07-31T02:40:25+00:00

CONFIG_ARCH_ENABLE_THP_MIGRATION gates PMD-level migration entries. PMD-level device-private entries use the same migration mechanism and therefore require the same architecture support. Upcoming PMD-level swap entries can use the same PMD softleaf helpers without depending on page migration, so rename the architecture gate to CONFIG_ARCH_HAS_PMD_SOFTLEAVES. This describes the PMD entry capability rather than one current user of it. This is a pure rename: the set of selecting architectures (x86, arm64, s390, riscv, loongarch, and powerpc on PPC_BOOK3S_64) and the gating semantics are unchanged. No functional change intended. Link: https://lore.kernel.org/20260706114320.1643046-7-usama.arif@linux.dev Signed-off-by: Usama Arif Reviewed-by: Zi Yan Acked-by: David Hildenbrand (Arm) Cc: Alexandre Ghiti Cc: Baolin Wang Cc: Baoquan He Cc: Barry Song Cc: Chris Li Cc: Dev Jain Cc: "Huang, Ying" Cc: Johannes Weiner Cc: Kairui Song Cc: Kemeng Shi Cc: Kiryl Shutsemau Cc: Lance Yang Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Matthew Wilcox (Oracle) Cc: Nhat Pham Cc: Nico Pache Cc: Rik van Riel Cc: Ryan Roberts Cc: Shakeel Butt Cc: Vlastimil Babka Signed-off-by: Andrew Morton

mm: cleanup clear_not_present_full_ptes() and rename to clear_non_present_ptes()

2026-07-29T04:12:10+00:00

Let's clean it up a bit: (1) There is no need to pass "full" anymore. (2) No architecture overwrites it, and there isn't really a good reason to do so when dealing with non-present PTEs. (3) While at it, call it "non-present", similar to copy_nonpresent_pte() and zap_nonpresent_ptes(). It's a shame that we have clear_non_present_ptes() correspond to pte_clear() and clear_ptes() correspond to ptep_get_and_clear*(). Link: https://lore.kernel.org/20260629-clear_not_present_full_ptes-v2-3-96089871a1e7@kernel.org Signed-off-by: David Hildenbrand (Arm) Reviewed-by: Oscar Salvador (SUSE) Reviewed-by: Lance Yang Cc: Andreas Larsson Cc: David S. Miller Cc: Jann Horn Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Mike Rapoport Cc: Peter Zijlstra Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

mm: drop pte_clear_not_present_full()

2026-07-29T04:12:09+00:00

In general, there is no good reason to do anything special when clearing non-present PTEs. In theory, HW that does have to invalidate TLBs for non-present PTEs could benefit from a "full" parameter, but fortunately pte_clear_not_present_full() is not wired up anymore ... and there would have to be something very convincing for us to care about that to re-add it. So, let's just use pte_clear() directly now. To prevent the compiler complaining on some configs about "set but not used" addr parameter, silence that here. Link: https://lore.kernel.org/20260629-clear_not_present_full_ptes-v2-2-96089871a1e7@kernel.org Signed-off-by: David Hildenbrand (Arm) Reviewed-by: Oscar Salvador (SUSE) Reviewed-by: Lance Yang Cc: Andreas Larsson Cc: David S. Miller Cc: Jann Horn Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Mike Rapoport Cc: Peter Zijlstra Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

mm: replace ASSEMBLY with ASSEMBLER in memory management header files

2026-07-29T04:11:46+00:00

While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembly code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This can be very confusing when switching between userspace and kernelspace coding, or when dealing with uapi headers that rather should use __ASSEMBLER__ instead. So let's standardize now on the __ASSEMBLER__ macro that is provided by the compilers. This is a completely mechanical patch (done with a simple "sed -i" statement). Link: https://lore.kernel.org/20260619131830.229804-1-thuth@redhat.com Signed-off-by: Thomas Huth Cc: Arnd Bergmann Cc: Axel Rasmussen Cc: Barry Song Cc: David Hildenbrand Cc: Kairui Song Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Mike Rapoport Cc: Shakeel Butt Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Wei Xu Cc: Yuanchu Xie Signed-off-by: Andrew Morton

Merge tag 'bpf-next-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2026-06-17T08:18:14+00:00

Pull bpf updates from Alexei Starovoitov: "Major changes: - Recover from BPF arena page faults using a scratch page and add ptep_try_set() for lockless empty-slot installs on x86 and arm64. This allows BPF kfuncs to access arena pointers directly. The 'arena_direct_access' stable branch was created for this work and was pulled into sched-ext and bpf-next trees (Tejun Heo, Kumar Kartikeya Dwivedi) - Lift old restriction and support 6+ arguments in BPF programs and kfuncs on x86 and arm64 (Yonghong Song, Puranjay Mohan) Other features and fixes: - Add 24-bit BTF vlen and reclaim unused bits in the BTF UAPI to ease addition of new BTF kinds (Alan Maguire) - Raise the maximum BPF call chain depth from 8 to 16 frames (Alexei Starovoitov) - Refactor object relationship tracking in the verifier and fix a dynptr use-after-free bug (Amery Hung) - Harden the signed program loader and reject exclusive maps as inner maps (Daniel Borkmann) - Replace the verifier min/max bounds fields with a circular number (cnum) representation and improve 32->64 bit range refinements (Eduard Zingerman) - Introduce the arena library and runtime (libarena) with a buddy allocator, rbtree and SPMC queue data structures, ASAN support and a parallel test harness. Allow subprograms to return arena pointers and switch to a BTF type-tag based __arena annotation (Emil Tsalapatis) - Cache build IDs in the sleepable stackmap path and avoid faultable build ID reads under mm locks (Ihor Solodrai) - Introduce the tracing_multi link to attach a single BPF program to many kernel functions at once. Allow specifying the uprobe_multi target via FD (Jiri Olsa) - Extend the bpf_list family of kfuncs with bpf_list_add/del(), and bpf_list_is_first/is_last/empty() (Kaitao Cheng) - Extend the BPF syscall with common attributes support for prog_load, btf_load and map_create (Leon Hwang) - Wrap rhashtable as BPF map (Mykyta Yatsenko, Herbert Xu) - Add sleepable support for tracepoint programs and fix deadlocks in LRU map due to NMI reentry (Mykyta Yatsenko) - Fix OOB access in bpf_flow_keys, fix nullness analysis of inner arrays, enforce write checks for global subprograms (Nuoqi Gui) - Report the maximum combined stack depth and print a breakdown of instructions processed per subprogram (Paul Chaignon) - Add an XDP load-balancer benchmark and arm64 JIT support for stack arguments (Puranjay Mohan) - Add kfuncs to traverse over wakeup_sources (Samuel Wu) - Allow sleepable BPF programs to use LPM trie maps directly (Vlad Poenaru) - Many more fixes and cleanups across the verifier, BTF, sockmap, devmap, bpffs, security hooks, s390/riscv/loongarch JITs, rqspinlock, libbpf, bpftool, selftests" * tag 'bpf-next-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (336 commits) selftests/bpf: Work around llvm stack overflow in crypto progs selftests/bpf: add test for bpf_msg_pop_data() overflow bpf, sockmap: fix integer overflow in bpf_msg_pop_data() bounds check sockmap: Fix use-after-free in udp_bpf_recvmsg() bpf, sockmap: keep sk_msg copy state in sync bpf, sockmap: Fix wrong rsge offset in bpf_msg_push_data() bpf, sockmap: reject overflowing copy + len in bpf_msg_push_data() selftsets/bpf: Retry map update on helper_fill_hashmap() selftests/bpf: Add test for sleepable lsm_cgroup rejection selftests/bpf: Add test to verify the fix for bpf_setsockopt() helper bpf: Fix bpf_get/setsockopt to tos for ipv4-mapped ipv6 socket selftests/bpf: Avoid static LLVM linking for cross builds selftests/bpf: Use common CFLAGS for urandom_read selftests/bpf: Initialize operation name before use tools/bpf: build: Append extra cflags libbpf: Initialize CFLAGS before including Makefile.include bpftool: Append extra host flags bpftool: Avoid adding EXTRA_CFLAGS to HOST_CFLAGS bpftool: Pass host flags to bootstrap libbpf selftests/bpf: correct CONFIG_PPC64 macro name in comment ...

Merge tag 'arm64-upstream' of gitolite.kernel.org:pub/scm/linux/kernel/git/arm64/linux

2026-06-15T23:48:04+00:00

Pull arm64 updates from Will Deacon: "It feels like the new world of AI tooling has slowed us down a little on the feature side when compared to the fixes side. The extra rounds of Sashiko review have also pushed a few things out until next time. Still, there's some good foundational stuff here for the fpsimd code and hardening work towards removing the predictable linear alias of the kernel image. CPU errata handling: - Extend CnP disabling workaround to HiSilicon HIP09 hardware. - Work around eternally broken broadcast TLB invalidation on more CPUs. - Documentation and code cleanups. CPU features: - Add new hwcaps for the 2025 dpISA extensions. Floating point / SVE / SME: - Significant cleanup to the low-level state management code in the core architecture code and KVM. - Use correct register widths during SVE/SME save/restore assembly. - Expose SVE/SME save/restore memory accesses to sanitisers. Memory management: - Preparatory work for unmapping the kernel data and bss sections from the linear map. Miscellaneous: - Inline DAIF manipulation helpers so they can be used safely from non-instrumentable code. - Fix handling of the 'nosmp' cmdline option to avoid marking secondary cores as "possible". MPAM: - Add support for v0.1 of the MPAM architecture. Perf: - Update HiSilicon PMU MAINTAINERS entry. - Fix event encodings for the DVM node in the CMN driver. Selftests: - Extend sigframe tests to cover POE context. - Add coverage for the newly added 2025 dpISA hwcaps. System registers: - Add new registers and ESR encodings for the HDBSS feature. Plus minor fixes and cleanups across the board" * tag 'arm64-upstream' of gitolite.kernel.org:pub/scm/linux/kernel/git/arm64/linux: (73 commits) arm64: errata: Mitigate TLBI errata on Microsoft Azure Cobalt 100 CPU arm64: errata: Mitigate TLBI errata on NVIDIA Olympus CPU arm64: errata: Mitigate TLBI errata on various Arm CPUs arm64: cputype: Add C1-Premium definitions arm64: cputype: Add C1-Ultra definitions Revert "arm64: mm: Unmap kernel data/bss entirely from the linear map" Revert "arm64: mm: Defer remap of linear alias of data/bss" arm64: arch_timer: reuse arch_timer_read_cnt{p,v}ct_el0() helpers arm64/mm: Rename ptdesc_t arm64: mm: Defer remap of linear alias of data/bss KVM: arm64: Omit tag sync on stage-2 mappings of the zero page arm64: Avoid double evaluation of __ptep_get() kasan: Move generic KASAN page tables out of BSS too arm64: Rename page table BSS section to .bss..pgtbl arm64: patching: replace min_t with min in __text_poke perf/arm-cmn: Fix DVM node events arm64: fpsimd: Remove arm64: fpsimd: Move SME save/restore inline arm64: fpsimd: Move sve_flush_live() inline arm64: fpsimd: Move SVE save/restore inline ...

mm: Refactor lazy_mmu_mode_pause() and lazy_mmu_mode_resume()

2026-06-08T07:21:06+00:00

In order to allow pausing and resuming MMU lazy mode for other tasks than current, refactor lazy_mmu_mode_pause() and lazy_mmu_mode_resume(). This will be needed when dropping the Xen PV private lazy MMU bookkeeping. Acked-by: "David Hildenbrand (Arm)" Signed-off-by: Juergen Gross Message-ID: <20260526150514.129330-4-jgross@suse.com>

bpf: Replace scratch PTE atomically when allocating arena pages

2026-06-05T15:22:36+00:00

apply_range_set_cb() maps the pages for a new arena allocation and returned -EBUSY when the target PTE was already populated. Kernel-fault recovery leaves the per-arena scratch page in unallocated arena PTEs, so a later bpf_arena_alloc_pages() over such a page hits that -EBUSY, and every subsequent allocation of it fails the same way. Allocation must install the real page over scratch instead. Overwriting the scratch PTE in place is a valid->valid change, which arm64 forbids without break-before-make. Route through an invalid entry instead: ptep_try_set() fills only a none slot, so the PTE goes scratch->none->page. On finding scratch, clear it and flush_tlb_before_set() before retrying. The new flush_tlb_before_set() is a no-op except on arches like arm64 that need the break-before-make TLB invalidate. The loop also copes with a concurrent fault re-scratching the slot. Arches without ptep_try_set() never install the scratch page, so keep the must-be-empty check and set_pte_at() for them. Fixes: dc11a4dba246 ("bpf: Recover arena kernel faults with scratch page") Signed-off-by: Tejun Heo Cc: Alexei Starovoitov Cc: David Hildenbrand Acked-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20260601183728.1800490-1-tj@kernel.org Signed-off-by: Alexei Starovoitov

mm: Make empty_zero_page[] const

2026-06-02T15:29:16+00:00

The empty zero page is used to back any kernel or user space mapping that is supposed to remain cleared, and so the page itself is never supposed to be modified. So mark it as const, which moves it into .rodata rather than .bss: on most architectures, this ensures that both the kernel's mapping of it and any aliases that are accessible via the kernel direct (linear) map are mapped read-only, and cannot be used (inadvertently or maliciously) to corrupt the contents of the zero page. Reviewed-by: Mike Rapoport (Microsoft) Reviewed-by: Kevin Brodsky Acked-by: David Hildenbrand (Arm) Reviewed-by: Jann Horn Reviewed-by: Feng Tang Signed-off-by: Ard Biesheuvel Signed-off-by: Will Deacon