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9 daysarm64: add batched versions of ptep_modify_prot_start/commitDev Jain
Override the generic definition of modify_prot_start_ptes() to use get_and_clear_full_ptes(). This helper does a TLBI only for the starting and ending contpte block of the range, whereas the current implementation will call ptep_get_and_clear() for every contpte block, thus doing a TLBI on every contpte block. Therefore, we have a performance win. The arm64 definition of pte_accessible() allows us to batch in the errata specific case: #define pte_accessible(mm, pte) \ (mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte)) All ptes are obviously present in the folio batch, and they are also valid. Override the generic definition of modify_prot_commit_ptes() to simply use set_ptes() to map the new ptes into the pagetable. Link: https://lkml.kernel.org/r/20250718090244.21092-8-dev.jain@arm.com Signed-off-by: Dev Jain <dev.jain@arm.com> Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Barry Song <baohua@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: David Hildenbrand <david@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jann Horn <jannh@google.com> Cc: Joey Gouly <joey.gouly@arm.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Lance Yang <ioworker0@gmail.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Cc: Yang Shi <yang@os.amperecomputing.com> Cc: Yicong Yang <yangyicong@hisilicon.com> Cc: Zhenhua Huang <quic_zhenhuah@quicinc.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09mm: remove devmap related functions and page table bitsAlistair Popple
Now that DAX and all other reference counts to ZONE_DEVICE pages are managed normally there is no need for the special devmap PTE/PMD/PUD page table bits. So drop all references to these, freeing up a software defined page table bit on architectures supporting it. Link: https://lkml.kernel.org/r/6389398c32cc9daa3dfcaa9f79c7972525d310ce.1750323463.git-series.apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Acked-by: Will Deacon <will@kernel.org> # arm64 Acked-by: David Hildenbrand <david@redhat.com> Suggested-by: Chunyan Zhang <zhang.lyra@gmail.com> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Balbir Singh <balbirs@nvidia.com> Cc: Björn Töpel <bjorn@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Deepak Gupta <debug@rivosinc.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Inki Dae <m.szyprowski@samsung.com> Cc: John Groves <john@groves.net> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09mm/filemap: allow arch to request folio size for exec memoryRyan Roberts
Change the readahead config so that if it is being requested for an executable mapping, do a synchronous read into a set of folios with an arch-specified order and in a naturally aligned manner. We no longer center the read on the faulting page but simply align it down to the previous natural boundary. Additionally, we don't bother with an asynchronous part. On arm64 if memory is physically contiguous and naturally aligned to the "contpte" size, we can use contpte mappings, which improves utilization of the TLB. When paired with the "multi-size THP" feature, this works well to reduce dTLB pressure. However iTLB pressure is still high due to executable mappings having a low likelihood of being in the required folio size and mapping alignment, even when the filesystem supports readahead into large folios (e.g. XFS). The reason for the low likelihood is that the current readahead algorithm starts with an order-0 folio and increases the folio order by 2 every time the readahead mark is hit. But most executable memory tends to be accessed randomly and so the readahead mark is rarely hit and most executable folios remain order-0. So let's special-case the read(ahead) logic for executable mappings. The trade-off is performance improvement (due to more efficient storage of the translations in iTLB) vs potential for making reclaim more difficult (due to the folios being larger so if a part of the folio is hot the whole thing is considered hot). But executable memory is a small portion of the overall system memory so I doubt this will even register from a reclaim perspective. I've chosen 64K folio size for arm64 which benefits both the 4K and 16K base page size configs. Crucially the same amount of data is still read (usually 128K) so I'm not expecting any read amplification issues. I don't anticipate any write amplification because text is always RO. Note that the text region of an ELF file could be populated into the page cache for other reasons than taking a fault in a mmapped area. The most common case is due to the loader read()ing the header which can be shared with the beginning of text. So some text will still remain in small folios, but this simple, best effort change provides good performance improvements as is. Confine this special-case approach to the bounds of the VMA. This prevents wasting memory for any padding that might exist in the file between sections. Previously the padding would have been contained in order-0 folios and would be easy to reclaim. But now it would be part of a larger folio so more difficult to reclaim. Solve this by simply not reading it into memory in the first place. Benchmarking ============ The below shows pgbench and redis benchmarks on Graviton3 arm64 system. First, confirmation that this patch causes more text to be contained in 64K folios: +----------------------+---------------+---------------+---------------+ | File-backed folios by| system boot | pgbench | redis | | size as percentage of+-------+-------+-------+-------+-------+-------+ | all mapped text mem |before | after |before | after |before | after | +======================+=======+=======+=======+=======+=======+=======+ | base-page-4kB | 78% | 30% | 78% | 11% | 73% | 14% | | thp-aligned-8kB | 1% | 0% | 0% | 0% | 1% | 0% | | thp-aligned-16kB | 17% | 4% | 17% | 3% | 20% | 4% | | thp-aligned-32kB | 1% | 1% | 1% | 2% | 1% | 1% | | thp-aligned-64kB | 3% | 63% | 3% | 81% | 4% | 77% | | thp-aligned-128kB | 0% | 1% | 1% | 1% | 1% | 2% | | thp-unaligned-64kB | 0% | 0% | 0% | 1% | 0% | 1% | | thp-unaligned-128kB | 0% | 1% | 0% | 0% | 0% | 0% | | thp-partial | 0% | 0% | 0% | 1% | 0% | 1% | +----------------------+-------+-------+-------+-------+-------+-------+ | cont-aligned-64kB | 4% | 65% | 4% | 83% | 6% | 79% | +----------------------+-------+-------+-------+-------+-------+-------+ The above shows that for both workloads (each isolated with cgroups) as well as the general system state after boot, the amount of text backed by 4K and 16K folios reduces and the amount backed by 64K folios increases significantly. And the amount of text that is contpte-mapped significantly increases (see last row). And this is reflected in performance improvement. "(I)" indicates a statistically significant improvement. Note TPS and Reqs/sec are rates so bigger is better, ms is time so smaller is better: +-------------+-------------------------------------------+------------+ | Benchmark | Result Class | Improvemnt | +=============+===========================================+============+ | pts/pgbench | Scale: 1 Clients: 1 RO (TPS) | (I) 3.47% | | | Scale: 1 Clients: 1 RO - Latency (ms) | -2.88% | | | Scale: 1 Clients: 250 RO (TPS) | (I) 5.02% | | | Scale: 1 Clients: 250 RO - Latency (ms) | (I) -4.79% | | | Scale: 1 Clients: 1000 RO (TPS) | (I) 6.16% | | | Scale: 1 Clients: 1000 RO - Latency (ms) | (I) -5.82% | | | Scale: 100 Clients: 1 RO (TPS) | 2.51% | | | Scale: 100 Clients: 1 RO - Latency (ms) | -3.51% | | | Scale: 100 Clients: 250 RO (TPS) | (I) 4.75% | | | Scale: 100 Clients: 250 RO - Latency (ms) | (I) -4.44% | | | Scale: 100 Clients: 1000 RO (TPS) | (I) 6.34% | | | Scale: 100 Clients: 1000 RO - Latency (ms)| (I) -5.95% | +-------------+-------------------------------------------+------------+ | pts/redis | Test: GET Connections: 50 (Reqs/sec) | (I) 3.20% | | | Test: GET Connections: 1000 (Reqs/sec) | (I) 2.55% | | | Test: LPOP Connections: 50 (Reqs/sec) | (I) 4.59% | | | Test: LPOP Connections: 1000 (Reqs/sec) | (I) 4.81% | | | Test: LPUSH Connections: 50 (Reqs/sec) | (I) 5.31% | | | Test: LPUSH Connections: 1000 (Reqs/sec) | (I) 4.36% | | | Test: SADD Connections: 50 (Reqs/sec) | (I) 2.64% | | | Test: SADD Connections: 1000 (Reqs/sec) | (I) 4.15% | | | Test: SET Connections: 50 (Reqs/sec) | (I) 3.11% | | | Test: SET Connections: 1000 (Reqs/sec) | (I) 3.36% | +-------------+-------------------------------------------+------------+ [ryan.roberts@arm.com: fix use-after-free] Link: https://lkml.kernel.org/r/ea7f9da7-9a9f-4b85-9d0a-35b320f5ed25@arm.com [ryan.roberts@arm.com: use the vma_pages() helper instead of open-coding] Link: https://lkml.kernel.org/r/0e0f674b-3b7e-494f-ae7a-fc9dbb98dad4@arm.com Link: https://lkml.kernel.org/r/20250609092729.274960-6-ryan.roberts@arm.com Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Reviewed-by: Jan Kara <jack@suse.cz> Acked-by: Will Deacon <will@kernel.org> Cc: Chaitanya S Prakash <chaitanyas.prakash@arm.com> Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-06-11mm: pgtable: fix pte_swp_exclusiveMagnus Lindholm
Make pte_swp_exclusive return bool instead of int. This will better reflect how pte_swp_exclusive is actually used in the code. This fixes swap/swapoff problems on Alpha due pte_swp_exclusive not returning correct values when _PAGE_SWP_EXCLUSIVE bit resides in upper 32-bits of PTE (like on alpha). Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Magnus Lindholm <linmag7@gmail.com> Cc: Sam James <sam@gentoo.org> Link: https://lore.kernel.org/lkml/20250218175735.19882-2-linmag7@gmail.com/ Link: https://lore.kernel.org/lkml/20250602041118.GA2675383@ZenIV/ [ Applied as the 'sed' script Al suggested - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2025-05-31Merge tag 'mm-stable-2025-05-31-14-50' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "Add folio_mk_pte()" from Matthew Wilcox simplifies the act of creating a pte which addresses the first page in a folio and reduces the amount of plumbing which architecture must implement to provide this. - "Misc folio patches for 6.16" from Matthew Wilcox is a shower of largely unrelated folio infrastructure changes which clean things up and better prepare us for future work. - "memory,x86,acpi: hotplug memory alignment advisement" from Gregory Price adds early-init code to prevent x86 from leaving physical memory unused when physical address regions are not aligned to memory block size. - "mm/compaction: allow more aggressive proactive compaction" from Michal Clapinski provides some tuning of the (sadly, hard-coded (more sadly, not auto-tuned)) thresholds for our invokation of proactive compaction. In a simple test case, the reduction of a guest VM's memory consumption was dramatic. - "Minor cleanups and improvements to swap freeing code" from Kemeng Shi provides some code cleaups and a small efficiency improvement to this part of our swap handling code. - "ptrace: introduce PTRACE_SET_SYSCALL_INFO API" from Dmitry Levin adds the ability for a ptracer to modify syscalls arguments. At this time we can alter only "system call information that are used by strace system call tampering, namely, syscall number, syscall arguments, and syscall return value. This series should have been incorporated into mm.git's "non-MM" branch, but I goofed. - "fs/proc: extend the PAGEMAP_SCAN ioctl to report guard regions" from Andrei Vagin extends the info returned by the PAGEMAP_SCAN ioctl against /proc/pid/pagemap. This permits CRIU to more efficiently get at the info about guard regions. - "Fix parameter passed to page_mapcount_is_type()" from Gavin Shan implements that fix. No runtime effect is expected because validate_page_before_insert() happens to fix up this error. - "kernel/events/uprobes: uprobe_write_opcode() rewrite" from David Hildenbrand basically brings uprobe text poking into the current decade. Remove a bunch of hand-rolled implementation in favor of using more current facilities. - "mm/ptdump: Drop assumption that pxd_val() is u64" from Anshuman Khandual provides enhancements and generalizations to the pte dumping code. This might be needed when 128-bit Page Table Descriptors are enabled for ARM. - "Always call constructor for kernel page tables" from Kevin Brodsky ensures that the ctor/dtor is always called for kernel pgtables, as it already is for user pgtables. This permits the addition of more functionality such as "insert hooks to protect page tables". This change does result in various architectures performing unnecesary work, but this is fixed up where it is anticipated to occur. - "Rust support for mm_struct, vm_area_struct, and mmap" from Alice Ryhl adds plumbing to permit Rust access to core MM structures. - "fix incorrectly disallowed anonymous VMA merges" from Lorenzo Stoakes takes advantage of some VMA merging opportunities which we've been missing for 15 years. - "mm/madvise: batch tlb flushes for MADV_DONTNEED and MADV_FREE" from SeongJae Park optimizes process_madvise()'s TLB flushing. Instead of flushing each address range in the provided iovec, we batch the flushing across all the iovec entries. The syscall's cost was approximately halved with a microbenchmark which was designed to load this particular operation. - "Track node vacancy to reduce worst case allocation counts" from Sidhartha Kumar makes the maple tree smarter about its node preallocation. stress-ng mmap performance increased by single-digit percentages and the amount of unnecessarily preallocated memory was dramaticelly reduced. - "mm/gup: Minor fix, cleanup and improvements" from Baoquan He removes a few unnecessary things which Baoquan noted when reading the code. - ""Enhance sysfs handling for memory hotplug in weighted interleave" from Rakie Kim "enhances the weighted interleave policy in the memory management subsystem by improving sysfs handling, fixing memory leaks, and introducing dynamic sysfs updates for memory hotplug support". Fixes things on error paths which we are unlikely to hit. - "mm/damon: auto-tune DAMOS for NUMA setups including tiered memory" from SeongJae Park introduces new DAMOS quota goal metrics which eliminate the manual tuning which is required when utilizing DAMON for memory tiering. - "mm/vmalloc.c: code cleanup and improvements" from Baoquan He provides cleanups and small efficiency improvements which Baoquan found via code inspection. - "vmscan: enforce mems_effective during demotion" from Gregory Price changes reclaim to respect cpuset.mems_effective during demotion when possible. because presently, reclaim explicitly ignores cpuset.mems_effective when demoting, which may cause the cpuset settings to violated. This is useful for isolating workloads on a multi-tenant system from certain classes of memory more consistently. - "Clean up split_huge_pmd_locked() and remove unnecessary folio pointers" from Gavin Guo provides minor cleanups and efficiency gains in in the huge page splitting and migrating code. - "Use kmem_cache for memcg alloc" from Huan Yang creates a slab cache for `struct mem_cgroup', yielding improved memory utilization. - "add max arg to swappiness in memory.reclaim and lru_gen" from Zhongkun He adds a new "max" argument to the "swappiness=" argument for memory.reclaim MGLRU's lru_gen. This directs proactive reclaim to reclaim from only anon folios rather than file-backed folios. - "kexec: introduce Kexec HandOver (KHO)" from Mike Rapoport is the first step on the path to permitting the kernel to maintain existing VMs while replacing the host kernel via file-based kexec. At this time only memblock's reserve_mem is preserved. - "mm: Introduce for_each_valid_pfn()" from David Woodhouse provides and uses a smarter way of looping over a pfn range. By skipping ranges of invalid pfns. - "sched/numa: Skip VMA scanning on memory pinned to one NUMA node via cpuset.mems" from Libo Chen removes a lot of pointless VMA scanning when a task is pinned a single NUMA mode. Dramatic performance benefits were seen in some real world cases. - "JFS: Implement migrate_folio for jfs_metapage_aops" from Shivank Garg addresses a warning which occurs during memory compaction when using JFS. - "move all VMA allocation, freeing and duplication logic to mm" from Lorenzo Stoakes moves some VMA code from kernel/fork.c into the more appropriate mm/vma.c. - "mm, swap: clean up swap cache mapping helper" from Kairui Song provides code consolidation and cleanups related to the folio_index() function. - "mm/gup: Cleanup memfd_pin_folios()" from Vishal Moola does that. - "memcg: Fix test_memcg_min/low test failures" from Waiman Long addresses some bogus failures which are being reported by the test_memcontrol selftest. - "eliminate mmap() retry merge, add .mmap_prepare hook" from Lorenzo Stoakes commences the deprecation of file_operations.mmap() in favor of the new file_operations.mmap_prepare(). The latter is more restrictive and prevents drivers from messing with things in ways which, amongst other problems, may defeat VMA merging. - "memcg: decouple memcg and objcg stocks"" from Shakeel Butt decouples the per-cpu memcg charge cache from the objcg's one. This is a step along the way to making memcg and objcg charging NMI-safe, which is a BPF requirement. - "mm/damon: minor fixups and improvements for code, tests, and documents" from SeongJae Park is yet another batch of miscellaneous DAMON changes. Fix and improve minor problems in code, tests and documents. - "memcg: make memcg stats irq safe" from Shakeel Butt converts memcg stats to be irq safe. Another step along the way to making memcg charging and stats updates NMI-safe, a BPF requirement. - "Let unmap_hugepage_range() and several related functions take folio instead of page" from Fan Ni provides folio conversions in the hugetlb code. * tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (285 commits) mm: pcp: increase pcp->free_count threshold to trigger free_high mm/hugetlb: convert use of struct page to folio in __unmap_hugepage_range() mm/hugetlb: refactor __unmap_hugepage_range() to take folio instead of page mm/hugetlb: refactor unmap_hugepage_range() to take folio instead of page mm/hugetlb: pass folio instead of page to unmap_ref_private() memcg: objcg stock trylock without irq disabling memcg: no stock lock for cpu hot-unplug memcg: make __mod_memcg_lruvec_state re-entrant safe against irqs memcg: make count_memcg_events re-entrant safe against irqs memcg: make mod_memcg_state re-entrant safe against irqs memcg: move preempt disable to callers of memcg_rstat_updated memcg: memcg_rstat_updated re-entrant safe against irqs mm: khugepaged: decouple SHMEM and file folios' collapse selftests/eventfd: correct test name and improve messages alloc_tag: check mem_profiling_support in alloc_tag_init Docs/damon: update titles and brief introductions to explain DAMOS selftests/damon/_damon_sysfs: read tried regions directories in order mm/damon/tests/core-kunit: add a test for damos_set_filters_default_reject() mm/damon/paddr: remove unused variable, folio_list, in damon_pa_stat() mm/damon/sysfs-schemes: fix wrong comment on damons_sysfs_quota_goal_metric_strs ...
2025-05-16arm64/boot: Move init_pgdir[] and init_idmap_pgdir[] into __pi_ namespaceArd Biesheuvel
init_pgdir[] is only referenced from the startup code, but lives after BSS in the linker map. Before tightening the rules about accessing BSS from startup code, move init_pgdir[] into the __pi_ namespace, so it does not need to be exported explicitly. For symmetry, do the same with init_idmap_pgdir[], although it lives before BSS. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Yeoreum Yun <yeoreum.yun@arm.com> Reviewed-by: Yeoreum Yun <yeoreum.yun@arm.com> Link: https://lore.kernel.org/r/20250508114328.2460610-6-ardb+git@google.com Signed-off-by: Will Deacon <will@kernel.org>
2025-05-16arm64: mm: Drop redundant check in pmd_trans_huge()Gavin Shan
pmd_val(pmd) is redundant because a positive pmd_present(pmd) ensures a positive pmd_val(pmd) according to their definitions like below. #define pmd_val(x) ((x).pmd) #define pmd_present(pmd) pte_present(pmd_pte(pmd)) #define pte_present(pte) (pte_valid(pte) || pte_present_invalid(pte)) #define pte_valid(pte) (!!(pte_val(pte) & PTE_VALID)) #define pte_present_invalid(pte) \ ((pte_val(pte) & (PTE_VALID | PTE_PRESENT_INVALID)) == PTE_PRESENT_INVALID) pte_present() can't be positive unless either of the flag PTE_VALID or PTE_PRESENT_INVALID is set. In this case, pmd_val(pmd) should be positive either. So lets drop the redundant check pmd_val(pmd) and no functional changes intended. Signed-off-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Dev Jain <dev.jain@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Link: https://lore.kernel.org/r/20250508085251.204282-1-gshan@redhat.com Signed-off-by: Will Deacon <will@kernel.org>
2025-05-14arm64/mm: Permit lazy_mmu_mode to be nestedRyan Roberts
lazy_mmu_mode is not supposed to permit nesting. But in practice this does happen with CONFIG_DEBUG_PAGEALLOC, where a page allocation inside a lazy_mmu_mode section (such as zap_pte_range()) will change permissions on the linear map with apply_to_page_range(), which re-enters lazy_mmu_mode (see stack trace below). The warning checking that nesting was not happening was previously being triggered due to this. So let's relax by removing the warning and tolerate nesting in the arm64 implementation. The first (inner) call to arch_leave_lazy_mmu_mode() will flush and clear the flag such that the remainder of the work in the outer nest behaves as if outside of lazy mmu mode. This is safe and keeps tracking simple. Code review suggests powerpc deals with this issue in the same way. ------------[ cut here ]------------ WARNING: CPU: 6 PID: 1 at arch/arm64/include/asm/pgtable.h:89 __apply_to_page_range+0x85c/0x9f8 Modules linked in: ip_tables x_tables ipv6 CPU: 6 UID: 0 PID: 1 Comm: systemd Not tainted 6.15.0-rc5-00075-g676795fe9cf6 #1 PREEMPT Hardware name: QEMU KVM Virtual Machine, BIOS 2024.08-4 10/25/2024 pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __apply_to_page_range+0x85c/0x9f8 lr : __apply_to_page_range+0x2b4/0x9f8 sp : ffff80008009b3c0 x29: ffff80008009b460 x28: ffff0000c43a3000 x27: ffff0001ff62b108 x26: ffff0000c43a4000 x25: 0000000000000001 x24: 0010000000000001 x23: ffffbf24c9c209c0 x22: ffff80008009b4d0 x21: ffffbf24c74a3b20 x20: ffff0000c43a3000 x19: ffff0001ff609d18 x18: 0000000000000001 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000003 x14: 0000000000000028 x13: ffffbf24c97c1000 x12: ffff0000c43a3fff x11: ffffbf24cacc9a70 x10: ffff0000c43a3fff x9 : ffff0001fffff018 x8 : 0000000000000012 x7 : ffff0000c43a4000 x6 : ffff0000c43a4000 x5 : ffffbf24c9c209c0 x4 : ffff0000c43a3fff x3 : ffff0001ff609000 x2 : 0000000000000d18 x1 : ffff0000c03e8000 x0 : 0000000080000000 Call trace: __apply_to_page_range+0x85c/0x9f8 (P) apply_to_page_range+0x14/0x20 set_memory_valid+0x5c/0xd8 __kernel_map_pages+0x84/0xc0 get_page_from_freelist+0x1110/0x1340 __alloc_frozen_pages_noprof+0x114/0x1178 alloc_pages_mpol+0xb8/0x1d0 alloc_frozen_pages_noprof+0x48/0xc0 alloc_pages_noprof+0x10/0x60 get_free_pages_noprof+0x14/0x90 __tlb_remove_folio_pages_size.isra.0+0xe4/0x140 __tlb_remove_folio_pages+0x10/0x20 unmap_page_range+0xa1c/0x14c0 unmap_single_vma.isra.0+0x48/0x90 unmap_vmas+0xe0/0x200 vms_clear_ptes+0xf4/0x140 vms_complete_munmap_vmas+0x7c/0x208 do_vmi_align_munmap+0x180/0x1a8 do_vmi_munmap+0xac/0x188 __vm_munmap+0xe0/0x1e0 __arm64_sys_munmap+0x20/0x38 invoke_syscall+0x48/0x104 el0_svc_common.constprop.0+0x40/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x4c/0x16c el0t_64_sync_handler+0x10c/0x140 el0t_64_sync+0x198/0x19c irq event stamp: 281312 hardirqs last enabled at (281311): [<ffffbf24c780fd04>] bad_range+0x164/0x1c0 hardirqs last disabled at (281312): [<ffffbf24c89c4550>] el1_dbg+0x24/0x98 softirqs last enabled at (281054): [<ffffbf24c752d99c>] handle_softirqs+0x4cc/0x518 softirqs last disabled at (281019): [<ffffbf24c7450694>] __do_softirq+0x14/0x20 ---[ end trace 0000000000000000 ]--- Fixes: 5fdd05efa1cd ("arm64/mm: Batch barriers when updating kernel mappings") Reported-by: Catalin Marinas <catalin.marinas@arm.com> Closes: https://lore.kernel.org/linux-arm-kernel/aCH0TLRQslXHin5Q@arm.com/ Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20250512150333.5589-1-ryan.roberts@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2025-05-14arm64/mm: Disable barrier batching in interrupt contextsRyan Roberts
Commit 5fdd05efa1cd ("arm64/mm: Batch barriers when updating kernel mappings") enabled arm64 kernels to track "lazy mmu mode" using TIF flags in order to defer barriers until exiting the mode. At the same time, it added warnings to check that pte manipulations were never performed in interrupt context, because the tracking implementation could not deal with nesting. But it turns out that some debug features (e.g. KFENCE, DEBUG_PAGEALLOC) do manipulate ptes in softirq context, which triggered the warnings. So let's take the simplest and safest route and disable the batching optimization in interrupt contexts. This makes these users no worse off than prior to the optimization. Additionally the known offenders are debug features that only manipulate a single PTE, so there is no performance gain anyway. There may be some obscure case of encrypted/decrypted DMA with the dma_free_coherent called from an interrupt context, but again, this is no worse off than prior to the commit. Some options for supporting nesting were considered, but there is a difficult to solve problem if any code manipulates ptes within interrupt context but *outside of* a lazy mmu region. If this case exists, the code would expect the updates to be immediate, but because the task context may have already been in lazy mmu mode, the updates would be deferred, which could cause incorrect behaviour. This problem is avoided by always ensuring updates within interrupt context are immediate. Fixes: 5fdd05efa1cd ("arm64/mm: Batch barriers when updating kernel mappings") Reported-by: syzbot+5c0d9392e042f41d45c5@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-arm-kernel/681f2a09.050a0220.f2294.0006.GAE@google.com/ Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20250512102242.4156463-1-ryan.roberts@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2025-05-11arch: remove mk_pmd()Matthew Wilcox (Oracle)
There are now no callers of mk_huge_pmd() and mk_pmd(). Remove them. Link: https://lkml.kernel.org/r/20250402181709.2386022-12-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Zi Yan <ziy@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Muchun Song <muchun.song@linux.dev> Cc: Richard Weinberger <richard@nod.at> Cc: <x86@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11mm: introduce a common definition of mk_pte()Matthew Wilcox (Oracle)
Most architectures simply call pfn_pte(). Centralise that as the normal definition and remove the definition of mk_pte() from the architectures which have either that exact definition or something similar. Link: https://lkml.kernel.org/r/20250402181709.2386022-3-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> # s390 Cc: Zi Yan <ziy@nvidia.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Muchun Song <muchun.song@linux.dev> Cc: Richard Weinberger <richard@nod.at> Cc: <x86@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-09arm64/mm: Batch barriers when updating kernel mappingsRyan Roberts
Because the kernel can't tolerate page faults for kernel mappings, when setting a valid, kernel space pte (or pmd/pud/p4d/pgd), it emits a dsb(ishst) to ensure that the store to the pgtable is observed by the table walker immediately. Additionally it emits an isb() to ensure that any already speculatively determined invalid mapping fault gets canceled. We can improve the performance of vmalloc operations by batching these barriers until the end of a set of entry updates. arch_enter_lazy_mmu_mode() and arch_leave_lazy_mmu_mode() provide the required hooks. vmalloc improves by up to 30% as a result. Two new TIF_ flags are created; TIF_LAZY_MMU tells us if the task is in the lazy mode and can therefore defer any barriers until exit from the lazy mode. TIF_LAZY_MMU_PENDING is used to remember if any pte operation was performed while in the lazy mode that required barriers. Then when leaving lazy mode, if that flag is set, we emit the barriers. Since arch_enter_lazy_mmu_mode() and arch_leave_lazy_mmu_mode() are used for both user and kernel mappings, we need the second flag to avoid emitting barriers unnecessarily if only user mappings were updated. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Tested-by: Luiz Capitulino <luizcap@redhat.com> Link: https://lore.kernel.org/r/20250422081822.1836315-12-ryan.roberts@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2025-05-09arm64/mm: Hoist barriers out of set_ptes_anysz() loopRyan Roberts
set_ptes_anysz() previously called __set_pte() for each PTE in the range, which would conditionally issue a DSB and ISB to make the new PTE value immediately visible to the table walker if the new PTE was valid and for kernel space. We can do better than this; let's hoist those barriers out of the loop so that they are only issued once at the end of the loop. We then reduce the cost by the number of PTEs in the range. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Tested-by: Luiz Capitulino <luizcap@redhat.com> Link: https://lore.kernel.org/r/20250422081822.1836315-7-ryan.roberts@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2025-05-09arm64/mm: Refactor __set_ptes() and __ptep_get_and_clear()Ryan Roberts
Refactor __set_ptes(), set_pmd_at() and set_pud_at() so that they are all a thin wrapper around a new common __set_ptes_anysz(), which takes pgsize parameter. Additionally, refactor __ptep_get_and_clear() and pmdp_huge_get_and_clear() to use a new common __ptep_get_and_clear_anysz() which also takes a pgsize parameter. These changes will permit the huge_pte API to efficiently batch-set pgtable entries and take advantage of the future barrier optimizations. Additionally since the new *_anysz() helpers call the correct page_table_check_*_set() API based on pgsize, this means that huge_ptes will be able to get proper coverage. Currently the huge_pte API always uses the pte API which assumes an entry only covers a single page. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Tested-by: Luiz Capitulino <luizcap@redhat.com> Link: https://lore.kernel.org/r/20250422081822.1836315-5-ryan.roberts@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2025-03-28arm64: mm: Drop dead code for pud special bit handlingPeter Xu
Keith Busch observed some incorrect macros defined in arm64 code [1]. It turns out the two lines should never be needed and won't be exposed to anyone, because aarch64 doesn't select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD, hence ARCH_SUPPORTS_PUD_PFNMAP is always N. The only archs that support THP PUDs so far are x86 and powerpc. Instead of fixing the lines (with no way to test it..), remove the two lines that are in reality dead code, to avoid confusing readers. Fixes tag is attached to reflect where the wrong macros were introduced, but explicitly not copying stable, because there's no real issue to be fixed. So it's only about removing the dead code so far. [1] https://lore.kernel.org/all/Z9tDjOk-JdV_fCY4@kbusch-mbp.dhcp.thefacebook.com/#t Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Donald Dutile <ddutile@redhat.com> Cc: Will Deacon <will@kernel.org> Fixes: 3e509c9b03f9 ("mm/arm64: support large pfn mappings") Reported-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Donald Dutile <ddutile@redhat.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20250320183405.12659-1-peterx@redhat.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-03-25Merge branches 'for-next/amuv1-avg-freq', 'for-next/pkey_unrestricted', ↵Catalin Marinas
'for-next/sysreg', 'for-next/misc', 'for-next/pgtable-cleanups', 'for-next/kselftest', 'for-next/uaccess-mops', 'for-next/pie-poe-cleanup', 'for-next/cputype-kryo', 'for-next/cca-dma-address', 'for-next/drop-pxd_table_bit' and 'for-next/spectre-bhb-assume-vulnerable', remote-tracking branch 'arm64/for-next/perf' into for-next/core * arm64/for-next/perf: perf/arm_cspmu: Fix missing io.h include perf/arm_cspmu: Add PMEVFILT2R support perf/arm_cspmu: Generalise event filtering perf/arm_cspmu: Move register definitons to header drivers/perf: apple_m1: Support host/guest event filtering drivers/perf: apple_m1: Refactor event select/filter configuration perf/dwc_pcie: fix duplicate pci_dev devices perf/dwc_pcie: fix some unreleased resources perf/arm-cmn: Minor event type housekeeping perf: arm_pmu: Move PMUv3-specific data perf: apple_m1: Don't disable counter in m1_pmu_enable_event() perf: arm_v7_pmu: Don't disable counter in (armv7|krait_|scorpion_)pmu_enable_event() perf: arm_v7_pmu: Drop obvious comments for enabling/disabling counters and interrupts perf: arm_pmuv3: Don't disable counter in armv8pmu_enable_event() perf: arm_pmu: Don't disable counter in armpmu_add() perf: arm_pmuv3: Call kvm_vcpu_pmu_resync_el0() before enabling counters perf: arm_pmuv3: Add support for ARM Rainier PMU * for-next/amuv1-avg-freq: : Add support for AArch64 AMUv1-based average freq arm64: Utilize for_each_cpu_wrap for reference lookup arm64: Update AMU-based freq scale factor on entering idle arm64: Provide an AMU-based version of arch_freq_get_on_cpu cpufreq: Introduce an optional cpuinfo_avg_freq sysfs entry cpufreq: Allow arch_freq_get_on_cpu to return an error arch_topology: init capacity_freq_ref to 0 * for-next/pkey_unrestricted: : mm/pkey: Add PKEY_UNRESTRICTED macro selftest/powerpc/mm/pkey: fix build-break introduced by commit 00894c3fc917 selftests/powerpc: Use PKEY_UNRESTRICTED macro selftests/mm: Use PKEY_UNRESTRICTED macro mm/pkey: Add PKEY_UNRESTRICTED macro * for-next/sysreg: : arm64 sysreg updates arm64/sysreg: Enforce whole word match for open/close tokens arm64/sysreg: Fix unbalanced closing block arm64/sysreg: Add register fields for HFGWTR2_EL2 arm64/sysreg: Add register fields for HFGRTR2_EL2 arm64/sysreg: Add register fields for HFGITR2_EL2 arm64/sysreg: Add register fields for HDFGWTR2_EL2 arm64/sysreg: Add register fields for HDFGRTR2_EL2 arm64/sysreg: Update register fields for ID_AA64MMFR0_EL1 * for-next/misc: : Miscellaneous arm64 patches arm64: mm: Don't use %pK through printk arm64/fpsimd: Remove unused declaration fpsimd_kvm_prepare() * for-next/pgtable-cleanups: : arm64 pgtable accessors cleanup arm64/mm: Define PTDESC_ORDER arm64/kernel: Always use level 2 or higher for early mappings arm64/hugetlb: Consistently use pud_sect_supported() arm64/mm: Convert __pte_to_phys() and __phys_to_pte_val() as functions * for-next/kselftest: : arm64 kselftest updates kselftest/arm64: mte: Skip the hugetlb tests if MTE not supported on such mappings kselftest/arm64: mte: Use the correct naming for tag check modes in check_hugetlb_options.c * for-next/uaccess-mops: : Implement the uaccess memory copy/set using MOPS instructions arm64: lib: Use MOPS for usercopy routines arm64: mm: Handle PAN faults on uaccess CPY* instructions arm64: extable: Add fixup handling for uaccess CPY* instructions * for-next/pie-poe-cleanup: : PIE/POE helpers cleanup arm64/sysreg: Move POR_EL0_INIT to asm/por.h arm64/sysreg: Rename POE_RXW to POE_RWX arm64/sysreg: Improve PIR/POR helpers * for-next/cputype-kryo: : Add cputype info for some Qualcomm Kryo cores arm64: cputype: Add comments about Qualcomm Kryo 5XX and 6XX cores arm64: cputype: Add QCOM_CPU_PART_KRYO_3XX_GOLD * for-next/cca-dma-address: : Fix DMA address for devices used in realms with Arm CCA arm64: realm: Use aliased addresses for device DMA to shared buffers dma: Introduce generic dma_addr_*crypted helpers dma: Fix encryption bit clearing for dma_to_phys * for-next/drop-pxd_table_bit: : Drop the arm64 PXD_TABLE_BIT (clean-up in preparation for 128-bit PTEs) arm64/mm: Drop PXD_TABLE_BIT arm64/mm: Check pmd_table() in pmd_trans_huge() arm64/mm: Check PUD_TYPE_TABLE in pud_bad() arm64/mm: Check PXD_TYPE_TABLE in [p4d|pgd]_bad() arm64/mm: Clear PXX_TYPE_MASK and set PXD_TYPE_SECT in [pmd|pud]_mkhuge() arm64/mm: Clear PXX_TYPE_MASK in mk_[pmd|pud]_sect_prot() arm64/ptdump: Test PMD_TYPE_MASK for block mapping KVM: arm64: ptdump: Test PMD_TYPE_MASK for block mapping * for-next/spectre-bhb-assume-vulnerable: : Rework Spectre BHB mitigations to not assume "safe" arm64: errata: Add newer ARM cores to the spectre_bhb_loop_affected() lists arm64: cputype: Add MIDR_CORTEX_A76AE arm64: errata: Add KRYO 2XX/3XX/4XX silver cores to Spectre BHB safe list arm64: errata: Assume that unknown CPUs _are_ vulnerable to Spectre BHB arm64: errata: Add QCOM_KRYO_4XX_GOLD to the spectre_bhb_k24_list
2025-03-12arm64/mm: Check pmd_table() in pmd_trans_huge()Ryan Roberts
Check for pmd_table() in pmd_trans_huge() rather then just checking for the PMD_TABLE_BIT. But ensure all present-invalid entries are handled correctly by always setting PTE_VALID before checking with pmd_table(). Cc: Will Deacon <will@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20250221044227.1145393-8-anshuman.khandual@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-03-12arm64/mm: Check PUD_TYPE_TABLE in pud_bad()Ryan Roberts
pud_bad() is currently defined in terms of pud_table(). Although for some configs, pud_table() is hard-coded to true i.e. when using 64K base pages or when page table levels are less than 3. pud_bad() is intended to check that the pud is configured correctly. Hence let's open-code the same check that the full version of pud_table() uses into pud_bad(). Then it always performs the check regardless of the config. Cc: Will Deacon <will@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20250221044227.1145393-7-anshuman.khandual@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-03-12arm64/mm: Check PXD_TYPE_TABLE in [p4d|pgd]_bad()Anshuman Khandual
Check page table entries against PXD_TYPE_TABLE on PXD_TYPE_MASK mask bits in [p4d|pgd]_bad() while determining a table entry instead of just checking only for PXD_TABLE_BIT. Cc: Will Deacon <will@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20250221044227.1145393-6-anshuman.khandual@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-03-12arm64/mm: Clear PXX_TYPE_MASK and set PXD_TYPE_SECT in [pmd|pud]_mkhuge()Anshuman Khandual
Clear PXX_TYPE_MASK in [pmd|pud]_mkhuge() while creating section mappings instead of just the PXX_TABLE_BIT and also set PXD_TYPE_SECT. Also ensure PTE_VALID does not get modified in these helpers, because present-invalid entries should preserve their state across. Cc: Will Deacon <will@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20250221044227.1145393-5-anshuman.khandual@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-03-12arm64/mm: Clear PXX_TYPE_MASK in mk_[pmd|pud]_sect_prot()Anshuman Khandual
Clear PXX_TYPE_MASK bits in mk_[pmd|pud]_sect_prot() while creating section mappings instead of just clearing the PXX_TABLE_BIT. Cc: Will Deacon <will@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20250221044227.1145393-4-anshuman.khandual@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-03-05arm64/mm: Convert __pte_to_phys() and __phys_to_pte_val() as functionsAnshuman Khandual
When CONFIG_ARM64_PA_BITS_52 is enabled, page table helpers __pte_to_phys() and __phys_to_pte_val() are functions which return phys_addr_t and pteval_t respectively as expected. But otherwise without this config being enabled, they are defined as macros and their return types are implicit. Until now this has worked out correctly as both pte_t and phys_addr_t data types have been 64 bits. But with the introduction of 128 bit page tables, pte_t becomes 128 bits. Hence this ends up with incorrect widths after the conversions, which leads to compiler warnings. Fix these warnings by converting __pte_to_phys() and __phys_to_pte_val() as functions instead where the return types are handled explicitly. Cc: Will Deacon <will@kernel.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Link: https://lore.kernel.org/r/20250227022412.2015835-1-anshuman.khandual@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-01-17Merge branch 'for-next/mm' into for-next/coreWill Deacon
* for-next/mm: arm64: mm: Test for pmd_sect() in vmemmap_check_pmd() arm64/mm: Replace open encodings with PXD_TABLE_BIT arm64/mm: Rename pte_mkpresent() as pte_mkvalid() arm64: Kconfig: force ARM64_PAN=y when enabling TTBR0 sw PAN arm64/kvm: Avoid invalid physical addresses to signal owner updates arm64/kvm: Configure HYP TCR.PS/DS based on host stage1 arm64/mm: Override PARange for !LPA2 and use it consistently arm64/mm: Reduce PA space to 48 bits when LPA2 is not enabled
2025-01-07arm64/mm: Replace open encodings with PXD_TABLE_BITAnshuman Khandual
[pgd|p4d]_bad() helpers have open encodings for their respective table bits which can be replaced with corresponding macros. This makes things clearer, thus improving their readability as well. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Link: https://lore.kernel.org/r/20250107015529.798319-1-anshuman.khandual@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2025-01-07arm64/mm: Rename pte_mkpresent() as pte_mkvalid()Anshuman Khandual
pte_present() is no longer synonymous with pte_valid() as it also tests for pte_present_invalid() as well. Hence pte_mkpresent() is misleading, because all that does is make an entry mapped, via setting PTE_VALID. Hence rename the helper as pte_mkvalid() which reflects its functionality appropriately. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20250107023016.829416-1-anshuman.khandual@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-12-10arm64: asm: Fix typo in pgtable.hZhu Jun
The word 'trasferring' is wrong, so fix it. Signed-off-by: Zhu Jun <zhujun2@cmss.chinamobile.com> Link: https://lore.kernel.org/r/20241203093323.7831-1-zhujun2@cmss.chinamobile.com Signed-off-by: Will Deacon <will@kernel.org>
2024-12-10arm64/mm: Replace open encodings with PXD_TABLE_BITAnshuman Khandual
[pgd|p4d]_bad() helpers have open encodings for their respective table bits which can be replaced with corresponding macros. This makes things clearer, thus improving their readability as well. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Link: https://lore.kernel.org/r/20241202083850.73207-1-anshuman.khandual@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-11-14Merge branches 'for-next/gcs', 'for-next/probes', 'for-next/asm-offsets', ↵Catalin Marinas
'for-next/tlb', 'for-next/misc', 'for-next/mte', 'for-next/sysreg', 'for-next/stacktrace', 'for-next/hwcap3', 'for-next/kselftest', 'for-next/crc32', 'for-next/guest-cca', 'for-next/haft' and 'for-next/scs', remote-tracking branch 'arm64/for-next/perf' into for-next/core * arm64/for-next/perf: perf: Switch back to struct platform_driver::remove() perf: arm_pmuv3: Add support for Samsung Mongoose PMU dt-bindings: arm: pmu: Add Samsung Mongoose core compatible perf/dwc_pcie: Fix typos in event names perf/dwc_pcie: Add support for Ampere SoCs ARM: pmuv3: Add missing write_pmuacr() perf/marvell: Marvell PEM performance monitor support perf/arm_pmuv3: Add PMUv3.9 per counter EL0 access control perf/dwc_pcie: Convert the events with mixed case to lowercase perf/cxlpmu: Support missing events in 3.1 spec perf: imx_perf: add support for i.MX91 platform dt-bindings: perf: fsl-imx-ddr: Add i.MX91 compatible drivers perf: remove unused field pmu_node * for-next/gcs: (42 commits) : arm64 Guarded Control Stack user-space support kselftest/arm64: Fix missing printf() argument in gcs/gcs-stress.c arm64/gcs: Fix outdated ptrace documentation kselftest/arm64: Ensure stable names for GCS stress test results kselftest/arm64: Validate that GCS push and write permissions work kselftest/arm64: Enable GCS for the FP stress tests kselftest/arm64: Add a GCS stress test kselftest/arm64: Add GCS signal tests kselftest/arm64: Add test coverage for GCS mode locking kselftest/arm64: Add a GCS test program built with the system libc kselftest/arm64: Add very basic GCS test program kselftest/arm64: Always run signals tests with GCS enabled kselftest/arm64: Allow signals tests to specify an expected si_code kselftest/arm64: Add framework support for GCS to signal handling tests kselftest/arm64: Add GCS as a detected feature in the signal tests kselftest/arm64: Verify the GCS hwcap arm64: Add Kconfig for Guarded Control Stack (GCS) arm64/ptrace: Expose GCS via ptrace and core files arm64/signal: Expose GCS state in signal frames arm64/signal: Set up and restore the GCS context for signal handlers arm64/mm: Implement map_shadow_stack() ... * for-next/probes: : Various arm64 uprobes/kprobes cleanups arm64: insn: Simulate nop instruction for better uprobe performance arm64: probes: Remove probe_opcode_t arm64: probes: Cleanup kprobes endianness conversions arm64: probes: Move kprobes-specific fields arm64: probes: Fix uprobes for big-endian kernels arm64: probes: Fix simulate_ldr*_literal() arm64: probes: Remove broken LDR (literal) uprobe support * for-next/asm-offsets: : arm64 asm-offsets.c cleanup (remove unused offsets) arm64: asm-offsets: remove PREEMPT_DISABLE_OFFSET arm64: asm-offsets: remove DMA_{TO,FROM}_DEVICE arm64: asm-offsets: remove VM_EXEC and PAGE_SZ arm64: asm-offsets: remove MM_CONTEXT_ID arm64: asm-offsets: remove COMPAT_{RT_,SIGFRAME_REGS_OFFSET arm64: asm-offsets: remove VMA_VM_* arm64: asm-offsets: remove TSK_ACTIVE_MM * for-next/tlb: : TLB flushing optimisations arm64: optimize flush tlb kernel range arm64: tlbflush: add __flush_tlb_range_limit_excess() * for-next/misc: : Miscellaneous patches arm64: tls: Fix context-switching of tpidrro_el0 when kpti is enabled arm64/ptrace: Clarify documentation of VL configuration via ptrace acpi/arm64: remove unnecessary cast arm64/mm: Change protval as 'pteval_t' in map_range() arm64: uprobes: Optimize cache flushes for xol slot acpi/arm64: Adjust error handling procedure in gtdt_parse_timer_block() arm64: fix .data.rel.ro size assertion when CONFIG_LTO_CLANG arm64/ptdump: Test both PTE_TABLE_BIT and PTE_VALID for block mappings arm64/mm: Sanity check PTE address before runtime P4D/PUD folding arm64/mm: Drop setting PTE_TYPE_PAGE in pte_mkcont() ACPI: GTDT: Tighten the check for the array of platform timer structures arm64/fpsimd: Fix a typo arm64: Expose ID_AA64ISAR1_EL1.XS to sanitised feature consumers arm64: Return early when break handler is found on linked-list arm64/mm: Re-organize arch_make_huge_pte() arm64/mm: Drop _PROT_SECT_DEFAULT arm64: Add command-line override for ID_AA64MMFR0_EL1.ECV arm64: head: Drop SWAPPER_TABLE_SHIFT arm64: cpufeature: add POE to cpucap_is_possible() arm64/mm: Change pgattr_change_is_safe() arguments as pteval_t * for-next/mte: : Various MTE improvements selftests: arm64: add hugetlb mte tests hugetlb: arm64: add mte support * for-next/sysreg: : arm64 sysreg updates arm64/sysreg: Update ID_AA64MMFR1_EL1 to DDI0601 2024-09 * for-next/stacktrace: : arm64 stacktrace improvements arm64: preserve pt_regs::stackframe during exec*() arm64: stacktrace: unwind exception boundaries arm64: stacktrace: split unwind_consume_stack() arm64: stacktrace: report recovered PCs arm64: stacktrace: report source of unwind data arm64: stacktrace: move dump_backtrace() to kunwind_stack_walk() arm64: use a common struct frame_record arm64: pt_regs: swap 'unused' and 'pmr' fields arm64: pt_regs: rename "pmr_save" -> "pmr" arm64: pt_regs: remove stale big-endian layout arm64: pt_regs: assert pt_regs is a multiple of 16 bytes * for-next/hwcap3: : Add AT_HWCAP3 support for arm64 (also wire up AT_HWCAP4) arm64: Support AT_HWCAP3 binfmt_elf: Wire up AT_HWCAP3 at AT_HWCAP4 * for-next/kselftest: (30 commits) : arm64 kselftest fixes/cleanups kselftest/arm64: Try harder to generate different keys during PAC tests kselftest/arm64: Don't leak pipe fds in pac.exec_sign_all() kselftest/arm64: Corrupt P0 in the irritator when testing SSVE kselftest/arm64: Add FPMR coverage to fp-ptrace kselftest/arm64: Expand the set of ZA writes fp-ptrace does kselftets/arm64: Use flag bits for features in fp-ptrace assembler code kselftest/arm64: Enable build of PAC tests with LLVM=1 kselftest/arm64: Check that SVCR is 0 in signal handlers kselftest/arm64: Fix printf() compiler warnings in the arm64 syscall-abi.c tests kselftest/arm64: Fix printf() warning in the arm64 MTE prctl() test kselftest/arm64: Fix printf() compiler warnings in the arm64 fp tests kselftest/arm64: Fix build with stricter assemblers kselftest/arm64: Test signal handler state modification in fp-stress kselftest/arm64: Provide a SIGUSR1 handler in the kernel mode FP stress test kselftest/arm64: Implement irritators for ZA and ZT kselftest/arm64: Remove unused ADRs from irritator handlers kselftest/arm64: Correct misleading comments on fp-stress irritators kselftest/arm64: Poll less often while waiting for fp-stress children kselftest/arm64: Increase frequency of signal delivery in fp-stress kselftest/arm64: Fix encoding for SVE B16B16 test ... * for-next/crc32: : Optimise CRC32 using PMULL instructions arm64/crc32: Implement 4-way interleave using PMULL arm64/crc32: Reorganize bit/byte ordering macros arm64/lib: Handle CRC-32 alternative in C code * for-next/guest-cca: : Support for running Linux as a guest in Arm CCA arm64: Document Arm Confidential Compute virt: arm-cca-guest: TSM_REPORT support for realms arm64: Enable memory encrypt for Realms arm64: mm: Avoid TLBI when marking pages as valid arm64: Enforce bounce buffers for realm DMA efi: arm64: Map Device with Prot Shared arm64: rsi: Map unprotected MMIO as decrypted arm64: rsi: Add support for checking whether an MMIO is protected arm64: realm: Query IPA size from the RMM arm64: Detect if in a realm and set RIPAS RAM arm64: rsi: Add RSI definitions * for-next/haft: : Support for arm64 FEAT_HAFT arm64: pgtable: Warn unexpected pmdp_test_and_clear_young() arm64: Enable ARCH_HAS_NONLEAF_PMD_YOUNG arm64: Add support for FEAT_HAFT arm64: setup: name 'tcr2' register arm64/sysreg: Update ID_AA64MMFR1_EL1 register * for-next/scs: : Dynamic shadow call stack fixes arm64/scs: Drop unused prototype __pi_scs_patch_vmlinux() arm64/scs: Deal with 64-bit relative offsets in FDE frames arm64/scs: Fix handling of DWARF augmentation data in CIE/FDE frames
2024-11-05arm64: pgtable: Warn unexpected pmdp_test_and_clear_young()Yicong Yang
Young bit operation on PMD table entry is only supported if FEAT_HAFT enabled system wide. Add a warning for notifying the misbehaviour. Signed-off-by: Yicong Yang <yangyicong@hisilicon.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20241102104235.62560-6-yangyicong@huawei.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-11-05arm64: Enable ARCH_HAS_NONLEAF_PMD_YOUNGYicong Yang
With the support of FEAT_HAFT, the NONLEAF_PMD_YOUNG can be enabled on arm64 since the hardware is capable of updating the AF flag for PMD table descriptor. Since the AF bit of the table descriptor shares the same bit position in block descriptors, we only need to implement arch_has_hw_nonleaf_pmd_young() and select related configs. The related pmd_young test/update operations keeps the same with and already implemented for transparent page support. Currently ARCH_HAS_NONLEAF_PMD_YOUNG is used to improve the efficiency of lru-gen aging. Signed-off-by: Yicong Yang <yangyicong@hisilicon.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20241102104235.62560-5-yangyicong@huawei.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-11-05arm64/mm: Sanity check PTE address before runtime P4D/PUD foldingArd Biesheuvel
The runtime P4D/PUD folding logic assumes that the respective pgd_t* and p4d_t* arguments are pointers into actual page tables that are part of the hierarchy being operated on. This may not always be the case, and we have been bitten once by this already [0], where the argument was actually a stack variable, and in this case, the logic does not work at all. So let's add a VM_BUG_ON() for each case, to ensure that the address of the provided page table entry is consistent with the address being translated. [0] https://lore.kernel.org/all/20240725090345.28461-1-will@kernel.org/T/#u Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20241105093919.1312049-2-ardb+git@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-11-04arm64/mm: Drop setting PTE_TYPE_PAGE in pte_mkcont()Anshuman Khandual
PTE_TYPE_PAGE bits were being set in pte_mkcont() because PTE_TABLE_BIT was being cleared in pte_mkhuge(). But after arch_make_huge_pte() modification in commit f8192813dcbe ("arm64/mm: Re-organize arch_make_huge_pte()"), which dropped pte_mkhuge() completely, setting back PTE_TYPE_PAGE bits is no longer necessary. Change pte_mkcont() to only set PTE_CONT. Cc: Will Deacon <will@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20241104041617.3804617-1-anshuman.khandual@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-11-01arm64/mm: Re-organize arch_make_huge_pte()Anshuman Khandual
Core HugeTLB defines a fallback definition for arch_make_huge_pte(), which calls platform provided pte_mkhuge(). But if any platform already provides an override for arch_make_huge_pte(), then it does not need to provide the helper pte_mkhuge(). arm64 override for arch_make_huge_pte() calls pte_mkhuge() internally, thus creating an impression, that both of these callbacks are being used in core HugeTLB and hence required to be defined. This drops off pte_mkhuge() which was never required to begin with as there could not be any section mappings at the PTE level. Re-organize arch_make_huge_pte() based on requested page size and create the entry for the applicable page table level as needed. It also removes a redundancy of clearing PTE_TABLE_BIT bit followed by setting both PTE_TABLE_BIT and PTE_VALID bits (via PTE_TYPE_MASK) in the pte, while creating CONT_PTE_SIZE size entries. Cc: Will Deacon <will@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20241029044529.2624785-1-anshuman.khandual@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-23arm64: Enable memory encrypt for RealmsSuzuki K Poulose
Use the memory encryption APIs to trigger a RSI call to request a transition between protected memory and shared memory (or vice versa) and updating the kernel's linear map of modified pages to flip the top bit of the IPA. This requires that block mappings are not used in the direct map for realm guests. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Co-developed-by: Steven Price <steven.price@arm.com> Signed-off-by: Steven Price <steven.price@arm.com> Link: https://lore.kernel.org/r/20241017131434.40935-10-steven.price@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-16arm64/mm: Change pgattr_change_is_safe() arguments as pteval_tAnshuman Khandual
pgattr_change_is_safe() processes two distinct page table entries that just happen to be 64 bits for all levels. This changes both arguments to reflect the actual data type being processed in the function. This change is important when moving to FEAT_D128 based 128 bit page tables because it makes it simple to change the entry size in one place. Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20241001045804.1119881-1-anshuman.khandual@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-09-21Merge tag 'mm-stable-2024-09-20-02-31' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Along with the usual shower of singleton patches, notable patch series in this pull request are: - "Align kvrealloc() with krealloc()" from Danilo Krummrich. Adds consistency to the APIs and behaviour of these two core allocation functions. This also simplifies/enables Rustification. - "Some cleanups for shmem" from Baolin Wang. No functional changes - mode code reuse, better function naming, logic simplifications. - "mm: some small page fault cleanups" from Josef Bacik. No functional changes - code cleanups only. - "Various memory tiering fixes" from Zi Yan. A small fix and a little cleanup. - "mm/swap: remove boilerplate" from Yu Zhao. Code cleanups and simplifications and .text shrinkage. - "Kernel stack usage histogram" from Pasha Tatashin and Shakeel Butt. This is a feature, it adds new feilds to /proc/vmstat such as $ grep kstack /proc/vmstat kstack_1k 3 kstack_2k 188 kstack_4k 11391 kstack_8k 243 kstack_16k 0 which tells us that 11391 processes used 4k of stack while none at all used 16k. Useful for some system tuning things, but partivularly useful for "the dynamic kernel stack project". - "kmemleak: support for percpu memory leak detect" from Pavel Tikhomirov. Teaches kmemleak to detect leaksage of percpu memory. - "mm: memcg: page counters optimizations" from Roman Gushchin. "3 independent small optimizations of page counters". - "mm: split PTE/PMD PT table Kconfig cleanups+clarifications" from David Hildenbrand. Improves PTE/PMD splitlock detection, makes powerpc/8xx work correctly by design rather than by accident. - "mm: remove arch_make_page_accessible()" from David Hildenbrand. Some folio conversions which make arch_make_page_accessible() unneeded. - "mm, memcg: cg2 memory{.swap,}.peak write handlers" fro David Finkel. Cleans up and fixes our handling of the resetting of the cgroup/process peak-memory-use detector. - "Make core VMA operations internal and testable" from Lorenzo Stoakes. Rationalizaion and encapsulation of the VMA manipulation APIs. With a view to better enable testing of the VMA functions, even from a userspace-only harness. - "mm: zswap: fixes for global shrinker" from Takero Funaki. Fix issues in the zswap global shrinker, resulting in improved performance. - "mm: print the promo watermark in zoneinfo" from Kaiyang Zhao. Fill in some missing info in /proc/zoneinfo. - "mm: replace follow_page() by folio_walk" from David Hildenbrand. Code cleanups and rationalizations (conversion to folio_walk()) resulting in the removal of follow_page(). - "improving dynamic zswap shrinker protection scheme" from Nhat Pham. Some tuning to improve zswap's dynamic shrinker. Significant reductions in swapin and improvements in performance are shown. - "mm: Fix several issues with unaccepted memory" from Kirill Shutemov. Improvements to the new unaccepted memory feature, - "mm/mprotect: Fix dax puds" from Peter Xu. Implements mprotect on DAX PUDs. This was missing, although nobody seems to have notied yet. - "Introduce a store type enum for the Maple tree" from Sidhartha Kumar. Cleanups and modest performance improvements for the maple tree library code. - "memcg: further decouple v1 code from v2" from Shakeel Butt. Move more cgroup v1 remnants away from the v2 memcg code. - "memcg: initiate deprecation of v1 features" from Shakeel Butt. Adds various warnings telling users that memcg v1 features are deprecated. - "mm: swap: mTHP swap allocator base on swap cluster order" from Chris Li. Greatly improves the success rate of the mTHP swap allocation. - "mm: introduce numa_memblks" from Mike Rapoport. Moves various disparate per-arch implementations of numa_memblk code into generic code. - "mm: batch free swaps for zap_pte_range()" from Barry Song. Greatly improves the performance of munmap() of swap-filled ptes. - "support large folio swap-out and swap-in for shmem" from Baolin Wang. With this series we no longer split shmem large folios into simgle-page folios when swapping out shmem. - "mm/hugetlb: alloc/free gigantic folios" from Yu Zhao. Nice performance improvements and code reductions for gigantic folios. - "support shmem mTHP collapse" from Baolin Wang. Adds support for khugepaged's collapsing of shmem mTHP folios. - "mm: Optimize mseal checks" from Pedro Falcato. Fixes an mprotect() performance regression due to the addition of mseal(). - "Increase the number of bits available in page_type" from Matthew Wilcox. Increases the number of bits available in page_type! - "Simplify the page flags a little" from Matthew Wilcox. Many legacy page flags are now folio flags, so the page-based flags and their accessors/mutators can be removed. - "mm: store zero pages to be swapped out in a bitmap" from Usama Arif. An optimization which permits us to avoid writing/reading zero-filled zswap pages to backing store. - "Avoid MAP_FIXED gap exposure" from Liam Howlett. Fixes a race window which occurs when a MAP_FIXED operqtion is occurring during an unrelated vma tree walk. - "mm: remove vma_merge()" from Lorenzo Stoakes. Major rotorooting of the vma_merge() functionality, making ot cleaner, more testable and better tested. - "misc fixups for DAMON {self,kunit} tests" from SeongJae Park. Minor fixups of DAMON selftests and kunit tests. - "mm: memory_hotplug: improve do_migrate_range()" from Kefeng Wang. Code cleanups and folio conversions. - "Shmem mTHP controls and stats improvements" from Ryan Roberts. Cleanups for shmem controls and stats. - "mm: count the number of anonymous THPs per size" from Barry Song. Expose additional anon THP stats to userspace for improved tuning. - "mm: finish isolate/putback_lru_page()" from Kefeng Wang: more folio conversions and removal of now-unused page-based APIs. - "replace per-quota region priorities histogram buffer with per-context one" from SeongJae Park. DAMON histogram rationalization. - "Docs/damon: update GitHub repo URLs and maintainer-profile" from SeongJae Park. DAMON documentation updates. - "mm/vdpa: correct misuse of non-direct-reclaim __GFP_NOFAIL and improve related doc and warn" from Jason Wang: fixes usage of page allocator __GFP_NOFAIL and GFP_ATOMIC flags. - "mm: split underused THPs" from Yu Zhao. Improve THP=always policy. This was overprovisioning THPs in sparsely accessed memory areas. - "zram: introduce custom comp backends API" frm Sergey Senozhatsky. Add support for zram run-time compression algorithm tuning. - "mm: Care about shadow stack guard gap when getting an unmapped area" from Mark Brown. Fix up the various arch_get_unmapped_area() implementations to better respect guard areas. - "Improve mem_cgroup_iter()" from Kinsey Ho. Improve the reliability of mem_cgroup_iter() and various code cleanups. - "mm: Support huge pfnmaps" from Peter Xu. Extends the usage of huge pfnmap support. - "resource: Fix region_intersects() vs add_memory_driver_managed()" from Huang Ying. Fix a bug in region_intersects() for systems with CXL memory. - "mm: hwpoison: two more poison recovery" from Kefeng Wang. Teaches a couple more code paths to correctly recover from the encountering of poisoned memry. - "mm: enable large folios swap-in support" from Barry Song. Support the swapin of mTHP memory into appropriately-sized folios, rather than into single-page folios" * tag 'mm-stable-2024-09-20-02-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (416 commits) zram: free secondary algorithms names uprobes: turn xol_area->pages[2] into xol_area->page uprobes: introduce the global struct vm_special_mapping xol_mapping Revert "uprobes: use vm_special_mapping close() functionality" mm: support large folios swap-in for sync io devices mm: add nr argument in mem_cgroup_swapin_uncharge_swap() helper to support large folios mm: fix swap_read_folio_zeromap() for large folios with partial zeromap mm/debug_vm_pgtable: Use pxdp_get() for accessing page table entries set_memory: add __must_check to generic stubs mm/vma: return the exact errno in vms_gather_munmap_vmas() memcg: cleanup with !CONFIG_MEMCG_V1 mm/show_mem.c: report alloc tags in human readable units mm: support poison recovery from copy_present_page() mm: support poison recovery from do_cow_fault() resource, kunit: add test case for region_intersects() resource: make alloc_free_mem_region() works for iomem_resource mm: z3fold: deprecate CONFIG_Z3FOLD vfio/pci: implement huge_fault support mm/arm64: support large pfn mappings mm/x86: support large pfn mappings ...
2024-09-17mm/arm64: support large pfn mappingsPeter Xu
Support huge pfnmaps by using bit 56 (PTE_SPECIAL) for "special" on pmds/puds. Provide the pmd/pud helpers to set/get special bit. There's one more thing missing for arm64 which is the pxx_pgprot() for pmd/pud. Add them too, which is mostly the same as the pte version by dropping the pfn field. These helpers are essential to be used in the new follow_pfnmap*() API to report valid pgprot_t results. Note that arm64 doesn't yet support huge PUD yet, but it's still straightforward to provide the pud helpers that we need altogether. Only PMD helpers will make an immediate benefit until arm64 will support huge PUDs first in general (e.g. in THPs). Link: https://lkml.kernel.org/r/20240826204353.2228736-19-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Gavin Shan <gshan@redhat.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Niklas Schnelle <schnelle@linux.ibm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-17mm: always define pxx_pgprot()Peter Xu
There're: - 8 archs (arc, arm64, include, mips, powerpc, s390, sh, x86) that support pte_pgprot(). - 2 archs (x86, sparc) that support pmd_pgprot(). - 1 arch (x86) that support pud_pgprot(). Always define them to be used in generic code, and then we don't need to fiddle with "#ifdef"s when doing so. Link: https://lkml.kernel.org/r/20240826204353.2228736-9-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Gavin Shan <gshan@redhat.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Niklas Schnelle <schnelle@linux.ibm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-04arm64: implement PKEYS supportJoey Gouly
Implement the PKEYS interface, using the Permission Overlay Extension. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20240822151113.1479789-19-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-09-04arm64: add pte_access_permitted_no_overlay()Joey Gouly
We do not want take POE into account when clearing the MTE tags. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20240822151113.1479789-18-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-09-04arm64: mask out POIndex when modifying a PTEJoey Gouly
When a PTE is modified, the POIndex must be masked off so that it can be modified. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20240822151113.1479789-16-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-07-25arm64: mm: Fix lockless walks with static and dynamic page-table foldingWill Deacon
Lina reports random oopsen originating from the fast GUP code when 16K pages are used with 4-level page-tables, the fourth level being folded at runtime due to lack of LPA2. In this configuration, the generic implementation of p4d_offset_lockless() will return a 'p4d_t *' corresponding to the 'pgd_t' allocated on the stack of the caller, gup_fast_pgd_range(). This is normally fine, but when the fourth level of page-table is folded at runtime, pud_offset_lockless() will offset from the address of the 'p4d_t' to calculate the address of the PUD in the same page-table page. This results in a stray stack read when the 'p4d_t' has been allocated on the stack and can send the walker into the weeds. Fix the problem by providing our own definition of p4d_offset_lockless() when CONFIG_PGTABLE_LEVELS <= 4 which returns the real page-table pointer rather than the address of the local stack variable. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/50360968-13fb-4e6f-8f52-1725b3177215@asahilina.net Fixes: 0dd4f60a2c76 ("arm64: mm: Add support for folding PUDs at runtime") Reported-by: Asahi Lina <lina@asahilina.net> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20240725090345.28461-1-will@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2024-05-19Merge tag 'mm-stable-2024-05-17-19-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull mm updates from Andrew Morton: "The usual shower of singleton fixes and minor series all over MM, documented (hopefully adequately) in the respective changelogs. Notable series include: - Lucas Stach has provided some page-mapping cleanup/consolidation/ maintainability work in the series "mm/treewide: Remove pXd_huge() API". - In the series "Allow migrate on protnone reference with MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's MPOL_PREFERRED_MANY mode, yielding almost doubled performance in one test. - In their series "Memory allocation profiling" Kent Overstreet and Suren Baghdasaryan have contributed a means of determining (via /proc/allocinfo) whereabouts in the kernel memory is being allocated: number of calls and amount of memory. - Matthew Wilcox has provided the series "Various significant MM patches" which does a number of rather unrelated things, but in largely similar code sites. - In his series "mm: page_alloc: freelist migratetype hygiene" Johannes Weiner has fixed the page allocator's handling of migratetype requests, with resulting improvements in compaction efficiency. - In the series "make the hugetlb migration strategy consistent" Baolin Wang has fixed a hugetlb migration issue, which should improve hugetlb allocation reliability. - Liu Shixin has hit an I/O meltdown caused by readahead in a memory-tight memcg. Addressed in the series "Fix I/O high when memory almost met memcg limit". - In the series "mm/filemap: optimize folio adding and splitting" Kairui Song has optimized pagecache insertion, yielding ~10% performance improvement in one test. - Baoquan He has cleaned up and consolidated the early zone initialization code in the series "mm/mm_init.c: refactor free_area_init_core()". - Baoquan has also redone some MM initializatio code in the series "mm/init: minor clean up and improvement". - MM helper cleanups from Christoph Hellwig in his series "remove follow_pfn". - More cleanups from Matthew Wilcox in the series "Various page->flags cleanups". - Vlastimil Babka has contributed maintainability improvements in the series "memcg_kmem hooks refactoring". - More folio conversions and cleanups in Matthew Wilcox's series: "Convert huge_zero_page to huge_zero_folio" "khugepaged folio conversions" "Remove page_idle and page_young wrappers" "Use folio APIs in procfs" "Clean up __folio_put()" "Some cleanups for memory-failure" "Remove page_mapping()" "More folio compat code removal" - David Hildenbrand chipped in with "fs/proc/task_mmu: convert hugetlb functions to work on folis". - Code consolidation and cleanup work related to GUP's handling of hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2". - Rick Edgecombe has developed some fixes to stack guard gaps in the series "Cover a guard gap corner case". - Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the series "mm/ksm: fix ksm exec support for prctl". - Baolin Wang has implemented NUMA balancing for multi-size THPs. This is a simple first-cut implementation for now. The series is "support multi-size THP numa balancing". - Cleanups to vma handling helper functions from Matthew Wilcox in the series "Unify vma_address and vma_pgoff_address". - Some selftests maintenance work from Dev Jain in the series "selftests/mm: mremap_test: Optimizations and style fixes". - Improvements to the swapping of multi-size THPs from Ryan Roberts in the series "Swap-out mTHP without splitting". - Kefeng Wang has significantly optimized the handling of arm64's permission page faults in the series "arch/mm/fault: accelerate pagefault when badaccess" "mm: remove arch's private VM_FAULT_BADMAP/BADACCESS" - GUP cleanups from David Hildenbrand in "mm/gup: consistently call it GUP-fast". - hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault path to use struct vm_fault". - selftests build fixes from John Hubbard in the series "Fix selftests/mm build without requiring "make headers"". - Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the series "Improved Memory Tier Creation for CPUless NUMA Nodes". Fixes the initialization code so that migration between different memory types works as intended. - David Hildenbrand has improved follow_pte() and fixed an errant driver in the series "mm: follow_pte() improvements and acrn follow_pte() fixes". - David also did some cleanup work on large folio mapcounts in his series "mm: mapcount for large folios + page_mapcount() cleanups". - Folio conversions in KSM in Alex Shi's series "transfer page to folio in KSM". - Barry Song has added some sysfs stats for monitoring multi-size THP's in the series "mm: add per-order mTHP alloc and swpout counters". - Some zswap cleanups from Yosry Ahmed in the series "zswap same-filled and limit checking cleanups". - Matthew Wilcox has been looking at buffer_head code and found the documentation to be lacking. The series is "Improve buffer head documentation". - Multi-size THPs get more work, this time from Lance Yang. His series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free" optimizes the freeing of these things. - Kemeng Shi has added more userspace-visible writeback instrumentation in the series "Improve visibility of writeback". - Kemeng Shi then sent some maintenance work on top in the series "Fix and cleanups to page-writeback". - Matthew Wilcox reduces mmap_lock traffic in the anon vma code in the series "Improve anon_vma scalability for anon VMAs". Intel's test bot reported an improbable 3x improvement in one test. - SeongJae Park adds some DAMON feature work in the series "mm/damon: add a DAMOS filter type for page granularity access recheck" "selftests/damon: add DAMOS quota goal test" - Also some maintenance work in the series "mm/damon/paddr: simplify page level access re-check for pageout" "mm/damon: misc fixes and improvements" - David Hildenbrand has disabled some known-to-fail selftests ni the series "selftests: mm: cow: flag vmsplice() hugetlb tests as XFAIL". - memcg metadata storage optimizations from Shakeel Butt in "memcg: reduce memory consumption by memcg stats". - DAX fixes and maintenance work from Vishal Verma in the series "dax/bus.c: Fixups for dax-bus locking"" * tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (426 commits) memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order selftests/mm: hugetlb_madv_vs_map: avoid test skipping by querying hugepage size at runtime mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_wp mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_fault selftests: cgroup: add tests to verify the zswap writeback path mm: memcg: make alloc_mem_cgroup_per_node_info() return bool mm/damon/core: fix return value from damos_wmark_metric_value mm: do not update memcg stats for NR_{FILE/SHMEM}_PMDMAPPED selftests: cgroup: remove redundant enabling of memory controller Docs/mm/damon/maintainer-profile: allow posting patches based on damon/next tree Docs/mm/damon/maintainer-profile: change the maintainer's timezone from PST to PT Docs/mm/damon/design: use a list for supported filters Docs/admin-guide/mm/damon/usage: fix wrong schemes effective quota update command Docs/admin-guide/mm/damon/usage: fix wrong example of DAMOS filter matching sysfs file selftests/damon: classify tests for functionalities and regressions selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None' selftests/damon/_damon_sysfs: find sysfs mount point from /proc/mounts selftests/damon/_damon_sysfs: check errors from nr_schemes file reads mm/damon/core: initialize ->esz_bp from damos_quota_init_priv() selftests/damon: add a test for DAMOS quota goal ...
2024-05-09arm64/mm: Fix pud_user_accessible_page() for PGTABLE_LEVELS <= 2Ryan Roberts
The recent change to use pud_valid() as part of the implementation of pud_user_accessible_page() fails to build when PGTABLE_LEVELS <= 2 because pud_valid() is not defined in that case. Fix this by defining pud_valid() to false for this case. This means that pud_user_accessible_page() will correctly always return false for this config. Fixes: f0f5863a0fb0 ("arm64/mm: Remove PTE_PROT_NONE bit") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202405082221.43rfWxz5-lkp@intel.com/ Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Link: https://lore.kernel.org/r/20240509122844.563320-1-ryan.roberts@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-05-05mm/arm64: override clear_young_dirty_ptes() batch helperLance Yang
The per-pte get_and_clear/modify/set approach would result in unfolding/refolding for contpte mappings on arm64. So we need to override clear_young_dirty_ptes() for arm64 to avoid it. Link: https://lkml.kernel.org/r/20240418134435.6092-3-ioworker0@gmail.com Signed-off-by: Lance Yang <ioworker0@gmail.com> Suggested-by: Barry Song <21cnbao@gmail.com> Suggested-by: Ryan Roberts <ryan.roberts@arm.com> Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jeff Xie <xiehuan09@gmail.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Peter Xu <peterx@redhat.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yin Fengwei <fengwei.yin@intel.com> Cc: Zach O'Keefe <zokeefe@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-03arm64/mm: Add uffd write-protect supportRyan Roberts
Let's use the newly-free PTE SW bit (58) to add support for uffd-wp. The standard handlers are implemented for set/test/clear for both pte and pmd. Additionally we must also track the uffd-wp state as a pte swp bit, so use a free swap pte bit (3). Acked-by: Peter Xu <peterx@redhat.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Link: https://lore.kernel.org/r/20240503144604.151095-5-ryan.roberts@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-05-03arm64/mm: Move PTE_PRESENT_INVALID to overlay PTE_NGRyan Roberts
PTE_PRESENT_INVALID was previously occupying bit 59, which when a PTE is valid can either be IGNORED, PBHA[0] or AttrIndex[3], depending on the HW configuration. In practice this is currently not a problem because PTE_PRESENT_INVALID can only be 1 when PTE_VALID=0 and upstream Linux always requires the bit set to 0 for a valid pte. However, if in future Linux wants to use the field (e.g. AttrIndex[3]) then we could end up with confusion when PTE_PRESENT_INVALID comes along and corrupts the field - we would ideally want to preserve it even for an invalid (but present) pte. The other problem with bit 59 is that it prevents the offset field of a swap entry within a swap pte from growing beyond 51 bits. By moving PTE_PRESENT_INVALID to a low bit we can lay the swap pte out so that the offset field could grow to 52 bits in future. So let's move PTE_PRESENT_INVALID to overlay PTE_NG (bit 11). There is no need to persist NG for a present-invalid entry; it is always set for user mappings and is not used by SW to derive any state from the pte. PTE_NS was considered instead of PTE_NG, but it is RES0 for non-secure SW, so there is a chance that future architecture may allocate the bit and we may therefore need to persist that bit for present-invalid ptes. These are both marginal benefits, but make things a bit tidier in my opinion. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Link: https://lore.kernel.org/r/20240503144604.151095-4-ryan.roberts@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-05-03arm64/mm: Remove PTE_PROT_NONE bitRyan Roberts
Currently the PTE_PRESENT_INVALID and PTE_PROT_NONE functionality explicitly occupy 2 bits in the PTE when PTE_VALID/PMD_SECT_VALID is clear. This has 2 significant consequences: - PTE_PROT_NONE consumes a precious SW PTE bit that could be used for other things. - The swap pte layout must reserve those same 2 bits and ensure they are both always zero for a swap pte. It would be nice to reclaim at least one of those bits. But PTE_PRESENT_INVALID, which since the previous patch, applies uniformly to page/block descriptors at any level when PTE_VALID is clear, can already give us most of what PTE_PROT_NONE requires: If it is set, then the pte is still considered present; pte_present() returns true and all the fields in the pte follow the HW interpretation (e.g. SW can safely call pte_pfn(), etc). But crucially, the HW treats the pte as invalid and will fault if it hits. So let's remove PTE_PROT_NONE entirely and instead represent PROT_NONE as a present but invalid pte (PTE_VALID=0, PTE_PRESENT_INVALID=1) with PTE_USER=0 and PTE_UXN=1. This is a unique combination that is not used anywhere else. The net result is a clearer, simpler, more generic encoding scheme that applies uniformly to all levels. Additionally we free up a PTE SW bit and a swap pte bit (bit 58 in both cases). Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Link: https://lore.kernel.org/r/20240503144604.151095-3-ryan.roberts@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-05-03arm64/mm: generalize PMD_PRESENT_INVALID for all levelsRyan Roberts
As preparation for the next patch, which frees up the PTE_PROT_NONE present pte and swap pte bit, generalize PMD_PRESENT_INVALID to PTE_PRESENT_INVALID. This will then be used to mark PROT_NONE ptes (and entries at any other level) in the next patch. While we're at it, fix up the swap pte format comment to include PTE_PRESENT_INVALID. This is not new, it just wasn't previously documented. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Link: https://lore.kernel.org/r/20240503144604.151095-2-ryan.roberts@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-04-25arm64: mm: swap: support THP_SWAP on hardware with MTEBarry Song
Commit d0637c505f8a1 ("arm64: enable THP_SWAP for arm64") brings up THP_SWAP on ARM64, but it doesn't enable THP_SWP on hardware with MTE as the MTE code works with the assumption tags save/restore is always handling a folio with only one page. The limitation should be removed as more and more ARM64 SoCs have this feature. Co-existence of MTE and THP_SWAP becomes more and more important. This patch makes MTE tags saving support large folios, then we don't need to split large folios into base pages for swapping out on ARM64 SoCs with MTE any more. arch_prepare_to_swap() should take folio rather than page as parameter because we support THP swap-out as a whole. It saves tags for all pages in a large folio. As now we are restoring tags based-on folio, in arch_swap_restore(), we may increase some extra loops and early-exitings while refaulting a large folio which is still in swapcache in do_swap_page(). In case a large folio has nr pages, do_swap_page() will only set the PTE of the particular page which is causing the page fault. Thus do_swap_page() runs nr times, and each time, arch_swap_restore() will loop nr times for those subpages in the folio. So right now the algorithmic complexity becomes O(nr^2). Once we support mapping large folios in do_swap_page(), extra loops and early-exitings will decrease while not being completely removed as a large folio might get partially tagged in corner cases such as, 1. a large folio in swapcache can be partially unmapped, thus, MTE tags for the unmapped pages will be invalidated; 2. users might use mprotect() to set MTEs on a part of a large folio. arch_thp_swp_supported() is dropped since ARM64 MTE was the only one who needed it. Link: https://lkml.kernel.org/r/20240322114136.61386-2-21cnbao@gmail.com Signed-off-by: Barry Song <v-songbaohua@oppo.com> Reviewed-by: Steven Price <steven.price@arm.com> Acked-by: Chris Li <chrisl@kernel.org> Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: David Hildenbrand <david@redhat.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Peter Xu <peterx@redhat.com> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: "Mike Rapoport (IBM)" <rppt@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>