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2025-11-25btrfs: raid56: prepare verify_bio_data_sectors() to support bs > ps casesQu Wenruo
The function verify_bio_data_sectors() assume each fs block can be mapped by one page, blocking bs > ps support for raid56. Prepare it for bs > ps cases by: - Make get_bio_sector_nr() to consider bs > ps cases The function is utilized to calculate the sector number of a device bio submitted by btrfs raid56 layer. - Assemble a local paddrs[] for checksum calculation - Open code btrfs_check_block_csum() btrfs_check_block_csum() only supports fs blocks backed by large folios. But for raid56 we can have fs blocks backed by multiple non-contiguous pages, e.g. direct IO, encoded read/write/send. So instead of using btrfs_check_block_csum(), open code it to use btrfs_calculate_block_csum_pages(). Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-11-25btrfs: raid56: prepare verify_one_sector() to support bs > ps casesQu Wenruo
The function verify_one_sector() assume each fs block can be mapped by one page, blocking bs > ps support for raid56. Prepare it for bs > ps cases by: - Introduce helpers to get a paddrs pointer Thankfully all the higher layer bio should still be aligned to fs block size, thus a fs block should still be fully covered by the bio. Introduce sector_paddrs_in_rbio() and rbio_stripe_paddrs(), which will return a paddrs pointer inside btrfs_raid_bio::bio_paddrs[] or stripe_paddrs[]. The pointer can be directly passed to btrfs_calculate_block_csum_pages() to verify the checksum. - Open code btrfs_check_block_csum() btrfs_check_block_csum() only supports fs blocks backed by large folios. But for raid56 we can have fs blocks backed by multiple non-contiguous pages, e.g. direct IO, encoded read/write/send. So instead of using btrfs_check_block_csum(), open code it to use btrfs_calculate_block_csum_pages(). Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-11-25btrfs: raid56: prepare recover_vertical() to support bs > ps casesQu Wenruo
Currently recover_vertical() assumes that every fs block can be mapped by one page, this is blocking bs > ps support for raid56. Prepare recover_vertical() to support bs > ps cases by: - Introduce recover_vertical_step() helper Which will recover a full step (min(PAGE_SIZE, sectorsize)). Now recover_vertical() will do the error check for the specified sector, do the recover step by step, then do the sector verification. - Fix a spelling error of get_rbio_vertical_errors() The old name has a typo: "veritical". Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-11-25btrfs: raid56: prepare generate_pq_vertical() for bs > ps casesQu Wenruo
Unlike btrfs_calculate_block_csum_pages(), we cannot handle multiple pages at the same time for P/Q generation. So here we introduce a new @step_nr, and various helpers to grab the sub-block page from the rbio, and generate the P/Q stripe page by page. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-11-25btrfs: raid56: introduce a new parameter to locate a sectorQu Wenruo
Since we cannot ensure that all bios from the higher layer are backed by large folios (e.g. direct IO, encoded read/write/send), we need the ability to locate sub-block (aka, a page) inside a full stripe. So the existing @stripe_nr + @sector_nr combination is not enough to locate such page for bs > ps cases. Introduce a new parameter, @step_nr, to locate the page of a larger fs block. The naming is following the conventions used inside btrfs elsewhere, where one step is min(sectorsize, PAGE_SIZE). It's still a preparation, only touching the following aspects: - btrfs_dump_rbio() To show the new @sector_nsteps member. - btrfs_raid_bio::sector_nsteps Recording how many steps there are inside a fs block. - Enlarge btrfs_raid_bio::*_paddrs[] size To take @sector_nsteps into consideration. - index_one_bio() - index_stripe_sectors() - memcpy_from_bio_to_stripe() - cache_rbio_pages() - need_read_stripe_sectors() Those functions are iterating *_paddrs[], which needs to take sector_nsteps into consideration. - Rename rbio_stripe_sector_index() to rbio_sector_index() The "stripe" part is not that helpful. And an extra ASSERT() before returning the result. - Add a new rbio_paddr_index() helper This will take the extra @step_nr into consideration. - The comments of btrfs_raid_bio Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-11-25btrfs: raid56: add an overview for the btrfs_raid_bio structureQu Wenruo
The structure needs to track both the pages from higher layer bio and internal pages, thus it can be a little complex to grasp. Add an overview of the structure, especially how we track different pages from higher layer bios and internal ones, to save some time for future developers. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-11-24hfsplus: introduce KUnit tests for HFS+ string operationsViacheslav Dubeyko
This patch implements the Kunit based set of unit tests for HFS+ string operations. It checks functionality of hfsplus_strcasecmp(), hfsplus_strcmp(), hfsplus_uni2asc(), hfsplus_asc2uni(), hfsplus_hash_dentry(), and hfsplus_compare_dentry(). ./tools/testing/kunit/kunit.py run --kunitconfig ./fs/hfsplus/.kunitconfig [14:38:05] Configuring KUnit Kernel ... [14:38:05] Building KUnit Kernel ... Populating config with: $ make ARCH=um O=.kunit olddefconfig Building with: $ make all compile_commands.json scripts_gdb ARCH=um O=.kunit --jobs=22 [14:38:09] Starting KUnit Kernel (1/1)... [14:38:09] ============================================================ Running tests with: $ .kunit/linux kunit.enable=1 mem=1G console=tty kunit_shutdown=halt [14:38:09] ============== hfsplus_unicode (27 subtests) =============== [14:38:09] [PASSED] hfsplus_strcasecmp_test [14:38:09] [PASSED] hfsplus_strcmp_test [14:38:09] [PASSED] hfsplus_unicode_edge_cases_test [14:38:09] [PASSED] hfsplus_unicode_boundary_test [14:38:09] [PASSED] hfsplus_uni2asc_basic_test [14:38:09] [PASSED] hfsplus_uni2asc_special_chars_test [14:38:09] [PASSED] hfsplus_uni2asc_buffer_test [14:38:09] [PASSED] hfsplus_uni2asc_corrupted_test [14:38:09] [PASSED] hfsplus_uni2asc_edge_cases_test [14:38:09] [PASSED] hfsplus_asc2uni_basic_test [14:38:09] [PASSED] hfsplus_asc2uni_special_chars_test [14:38:09] [PASSED] hfsplus_asc2uni_buffer_limits_test [14:38:09] [PASSED] hfsplus_asc2uni_edge_cases_test [14:38:09] [PASSED] hfsplus_asc2uni_decompose_test [14:38:09] [PASSED] hfsplus_hash_dentry_basic_test [14:38:09] [PASSED] hfsplus_hash_dentry_casefold_test [14:38:09] [PASSED] hfsplus_hash_dentry_special_chars_test [14:38:09] [PASSED] hfsplus_hash_dentry_decompose_test [14:38:09] [PASSED] hfsplus_hash_dentry_consistency_test [14:38:09] [PASSED] hfsplus_hash_dentry_edge_cases_test [14:38:09] [PASSED] hfsplus_compare_dentry_basic_test [14:38:09] [PASSED] hfsplus_compare_dentry_casefold_test [14:38:09] [PASSED] hfsplus_compare_dentry_special_chars_test [14:38:09] [PASSED] hfsplus_compare_dentry_length_test [14:38:09] [PASSED] hfsplus_compare_dentry_decompose_test [14:38:09] [PASSED] hfsplus_compare_dentry_edge_cases_test [14:38:09] [PASSED] hfsplus_compare_dentry_combined_flags_test [14:38:09] ================= [PASSED] hfsplus_unicode ================= [14:38:09] ============================================================ [14:38:09] Testing complete. Ran 27 tests: passed: 27 [14:38:09] Elapsed time: 3.875s total, 0.001s configuring, 3.707s building, 0.115s running v2 Rework memory management model. Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com> cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> cc: Yangtao Li <frank.li@vivo.com> cc: linux-fsdevel@vger.kernel.org Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
2025-11-24PCI: Validate pci_rebar_size_supported() inputIlpo Järvinen
According to Dan Carpenter, smatch detects issue with size parameter given to pci_rebar_size_supported(): drivers/pci/rebar.c:142 pci_rebar_size_supported() error: undefined (user controlled) shift '(((1))) << size' The problem is this call tree, which uses the 'size' from the user to shift in BIT() without validating it: __resource_resize_store # takes 'buf' from user sysfs write kstrtoul(buf, 0, &size) # converts to unsigned long pci_resize_resource # truncates to int pci_rebar_size_supported # BIT(size) without validation There could be similar problems also with pci_resize_resource() parameter values coming from drivers. Add 'size' validation to pci_rebar_size_supported(). There seems to be no SZ_128T prior to this so add one to be able to specify the largest size supported by the kernel (PCIe r7.0 spec already defines sizes even beyond 128TB but kernel does not yet support them). The issue looks older than the introduction of pci_rebar_size_supported() by bb1fabd0d94e ("PCI: Add pci_rebar_size_supported() helper"). It would be also nice to convert 'size' unsigned too everywhere, maybe even u8 but that is left as further work. Fixes: 8bb705e3e79d ("PCI: Add pci_resize_resource() for resizing BARs") Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Closes: https://lore.kernel.org/r/aSA1WiRG3RuhqZMY@stanley.mountain/ Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> [bhelgaas: commit log, add report URL] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20251124153740.2995-1-ilpo.jarvinen@linux.intel.com
2025-11-24pagemap: update BUDDY flag documentationRichard Weinberger
Since v4.6 the BUDDY flag is set for _all_ pages in the block and no longer just for the first one. This change was introduced by: commit 832fc1de01ae ("/proc/kpageflags: return KPF_BUDDY for "tail" buddy pages") Strictly speaking, this was an ABI change, but as nobody has noticed since 2016, let's just update the documentation. Link: https://lkml.kernel.org/r/20251122211920.3410371-1-richard@nod.at Signed-off-by: Richard Weinberger <richard@nod.at> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Vladimir Davydov <vdavydov@virtuozzo.com>> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm: swap: remove scan_swap_map_slots() references from commentsYoungjun Park
The scan_swap_map_slots() helper has been removed, but several comments still referred to it in swap allocation and reclaim paths. This patch cleans up those outdated references and reflows the affected comment blocks to match kernel coding style. Link: https://lkml.kernel.org/r/20251031065011.40863-6-youngjun.park@lge.com Signed-off-by: Youngjun Park <youngjun.park@lge.com> Reviewed-by: Baoquan He <bhe@redhat.com> Acked-by: Chris Li <chrisl@kernel.org> Cc: Barry Song <baohua@kernel.org> Cc: Kairui Song <kasong@tencent.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm: swap: change swap_alloc_slow() to voidYoungjun Park
swap_alloc_slow() does not need to return a bool, as all callers handle allocation results via the entry parameter. Update the function signature and remove return statements accordingly. Link: https://lkml.kernel.org/r/20251031065011.40863-5-youngjun.park@lge.com Signed-off-by: Youngjun Park <youngjun.park@lge.com> Reviewed-by: Kairui Song <kasong@tencent.com> Reviewed-by: Baoquan He <bhe@redhat.com> Acked-by: Chris Li <chrisl@kernel.org> Cc: Barry Song <baohua@kernel.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm, swap: remove redundant comment for read_swap_cache_asyncYoungjun Park
The function now manages get/put_swap_device() internally, making the comment explaining this behavior to callers unnecessary. Link: https://lkml.kernel.org/r/20251031065011.40863-4-youngjun.park@lge.com Signed-off-by: Youngjun Park <youngjun.park@lge.com> Reviewed-by: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Chris Li <chrisl@kernel.org> Cc: Kairui Song <kasong@tencent.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm, swap: use SWP_SOLIDSTATE to determine if swap is rotationalYoungjun Park
The current non rotational check is unreliable as the device's rotational status can be changed by a user via sysfs. Use the more reliable SWP_SOLIDSTATE flag which is set at swapon time, to ensure the nr_rotate_swap count remains consistent. Plus, it is easy to read and simple. Link: https://lkml.kernel.org/r/20251031065011.40863-3-youngjun.park@lge.com Fixes: 81a0298bdfab ("mm, swap: don't use VMA based swap readahead if HDD is used as swap") Signed-off-by: Youngjun Park <youngjun.park@lge.com> Reviewed-by: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Chris Li <chrisl@kernel.org> Cc: Kairui Song <kasong@tencent.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm, swap: fix memory leak in setup_clusters() error pathYoungjun Park
Patch series "mm: swap: small fixes and comment cleanups", v2. This series provides a few small fixes and cleanups for the swap code. The first patch fixes a memory leak in an error path that was recently introduced. The subsequent patches include minor logic adjustments and the removal of redundant comments. This patch (of 5): setup_clusters() could leak 'cluster_info' memory if an error occurred on a path that did not jump to the 'err_free' label. This patch simplifies the error handling by removing the goto label and instead calling free_cluster_info() on all error exit paths. The new logic is safe, as free_cluster_info() already handles NULL pointer inputs. Link: https://lkml.kernel.org/r/20251031065011.40863-1-youngjun.park@lge.com Link: https://lkml.kernel.org/r/20251031065011.40863-2-youngjun.park@lge.com Fixes: 07adc4cf1ecd ("mm, swap: implement dynamic allocation of swap table") Signed-off-by: Youngjun Park <youngjun.park@lge.com> Reviewed-by: Kairui Song <kasong@tencent.com> Reviewed-by: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Chris Li <chrisl@kernel.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm/swap: fix wrong plist empty check in swap_alloc_slow()Youngjun Park
swap_alloc_slow() was checking `si->avail_list` instead of `next->avail_list` when verifying if the next swap device is still in the list, which could cause unnecessary restarts during allocation. Link: https://lkml.kernel.org/r/20251119114136.594108-1-youngjun.park@lge.com Fixes: 8e689f8ea45f ("mm/swap: do not choose swap device according to numa node") Signed-off-by: Youngjun Park <youngjun.park@lge.com> Acked-by: Kairui Song <kasong@tencent.com> Reviewed-by: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Chris Li <chrisl@kernel.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm/damon/tests/sysfs-kunit: fix use after free on error pathDan Carpenter
Re-order these frees to avoid dereferencing "sysfs_target" after it has been freed. Link: https://lkml.kernel.org/r/aSBq5uSPIqsqH8zO@stanley.mountain Fixes: ee131696794c ("mm/damon/tests/sysfs-kunit: handle alloc failures on damon_sysfs_test_add_targets()") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Reviewed-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24hugetlb: add __read_mostly to sysctl_hugetlb_shm_groupGregory Price
sysctl bits are mostly-read values. Link: https://lkml.kernel.org/r/20251121194859.265259-2-gourry@gourry.net Signed-off-by: Gregory Price <gourry@gourry.net> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24tools/testing/vma: add missing stubLorenzo Stoakes
vm_flags_reset() is not available in the userland VMA tests, so add a stub which const-casts vma->vm_flags and avoids the upcoming removal of the vma->__vm_flags field. Link: https://lkml.kernel.org/r/4aff8bf7-d367-4ba3-90ad-13eef7a063fa@lucifer.local Fixes: c5c67c1de357 ("tools/testing/vma: eliminate dependency on vma->__vm_flags") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24zram: fix the issue that the write - back limits might overflowYuwen Chen
When the page size exceeds 4KB, if bd_wb_limit is set to a value that is not aligned with the page size, it will cause a numerical wrap-around issue for bd_wb_limit. For example, when the page size is set to 16KB and bd_wb_limit is set to 3, after one write-back operation, the value of bd_wb_limit will become -1. More seriously, since bd_wb_limit is an unsigned number, its value may become as large as 2^64 - 1. The core reason for this problem is that the unit of bd_wb_limit is 4KB. For example, when a write-back occurs on a system with a page size of 16KB, 4 needs to be subtracted from bd_wb_limit. This operation takes place in the zram_account_writeback_submit function. This patch fixes the issue by limiting bd_wb_limit to be an integer multiple of PAGE_SIZE / 4096. Link: https://lkml.kernel.org/r/tencent_5936CFE72BAB2BA76887BB69DCC1B5E67C05@qq.com Fixes: 1d69a3f8ae77 ("zram: idle writeback fixes and cleanup") Signed-off-by: Yuwen Chen <ywen.chen@foxmail.com> Acked-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Brian Geffon <bgeffon@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Richard Chang <richardycc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm: tweak __vma_enter_locked()Matthew Wilcox (Oracle)
Move the commentary on how __vma_enter_locked() behaves from the body of __vma_start_write() to the head of __vma_enter_locked() and merge it with the existing documentation. Also add a call to mmap_assert_write_locked(). Link: https://lkml.kernel.org/r/20251119042639.3937024-1-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm/memory-failure: remove the selection of RASXie Yuanbin
commit 97f0b13452198290799f ("tracing: add trace event for memory-failure") introduces the selection of RAS in memory-failure. This commit is just a tracing feature; in reality, there is no dependency between memory-failure and RAS. RAS increases the size of the bzImage image by 8k, which is very valuable for embedded devices. Move the memory-failure traceing code from ras_event.h to memory-failure.h and remove the selection of RAS. Link: https://lkml.kernel.org/r/20251119095943.67125-1-xieyuanbin1@huawei.com Signed-off-by: Xie Yuanbin <xieyuanbin1@huawei.com> Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Acked-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Borislav Petkov <bp@alien8.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24dt-bindings: riscv: Add Svrsw60t59b extension descriptionChunyan Zhang
Add description for the Svrsw60t59b extension (PTE Reserved for SW bits 60:59) extension which was ratified recently in riscv-non-isa/riscv-iommu. Link: https://lkml.kernel.org/r/20251113072806.795029-7-zhangchunyan@iscas.ac.cn Acked-by: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: Chunyan Zhang <zhangchunyan@iscas.ac.cn> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Conor Dooley <conor@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Deepak Gupta <debug@rivosinc.com> Cc: Jan Kara <jack@suse.cz> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Xu <peterx@redhat.com> Cc: Rob Herring <robh@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yuanchu Xie <yuanchu@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24riscv: mm: add userfaultfd write-protect supportChunyan Zhang
The Svrsw60t59b extension allows to free the PTE reserved bits 60 and 59 for software, this patch uses bit 60 for uffd-wp tracking Additionally for tracking the uffd-wp state as a PTE swap bit, we borrow bit 4 which is not involved into swap entry computation. Link: https://lkml.kernel.org/r/20251113072806.795029-6-zhangchunyan@iscas.ac.cn Signed-off-by: Chunyan Zhang <zhangchunyan@iscas.ac.cn> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Conor Dooley <conor.dooley@microchip.com> Cc: Conor Dooley <conor@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Deepak Gupta <debug@rivosinc.com> Cc: Jan Kara <jack@suse.cz> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Xu <peterx@redhat.com> Cc: Rob Herring <robh@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yuanchu Xie <yuanchu@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24riscv: mm: add soft-dirty page tracking supportChunyan Zhang
The Svrsw60t59b extension allows to free the PTE reserved bits 60 and 59 for software, this patch uses bit 59 for soft-dirty. To add swap PTE soft-dirty tracking, we borrow bit 3 which is available for swap PTEs on RISC-V systems. Link: https://lkml.kernel.org/r/20251113072806.795029-5-zhangchunyan@iscas.ac.cn Signed-off-by: Chunyan Zhang <zhangchunyan@iscas.ac.cn> Reviewed-by: Deepak Gupta <debug@rivosinc.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Conor Dooley <conor.dooley@microchip.com> Cc: Conor Dooley <conor@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Xu <peterx@redhat.com> Cc: Rob Herring <robh@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yuanchu Xie <yuanchu@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24riscv: add RISC-V Svrsw60t59b extension supportChunyan Zhang
The Svrsw60t59b extension allows to free the PTE reserved bits 60 and 59 for software to use. Link: https://lkml.kernel.org/r/20251113072806.795029-4-zhangchunyan@iscas.ac.cn Signed-off-by: Chunyan Zhang <zhangchunyan@iscas.ac.cn> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Deepak Gupta <debug@rivosinc.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Conor Dooley <conor.dooley@microchip.com> Cc: Conor Dooley <conor@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Xu <peterx@redhat.com> Cc: Rob Herring <robh@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yuanchu Xie <yuanchu@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm: userfaultfd: add pgtable_supports_uffd_wp()Chunyan Zhang
Some platforms can customize the PTE/PMD entry uffd-wp bit making it unavailable even if the architecture provides the resource. This patch adds a macro API pgtable_supports_uffd_wp() that allows architectures to define their specific implementations to check if the uffd-wp bit is available on which device the kernel is running. Also this patch is removing "ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP" and "ifdef CONFIG_PTE_MARKER_UFFD_WP" in favor of pgtable_supports_uffd_wp() and uffd_supports_wp_marker() checks respectively that default to IS_ENABLED(CONFIG_HAVE_ARCH_USERFAULTFD_WP) and "IS_ENABLED(CONFIG_HAVE_ARCH_USERFAULTFD_WP) && IS_ENABLED(CONFIG_PTE_MARKER_UFFD_WP)" if not overridden by the architecture, no change in behavior is expected. Link: https://lkml.kernel.org/r/20251113072806.795029-3-zhangchunyan@iscas.ac.cn Signed-off-by: Chunyan Zhang <zhangchunyan@iscas.ac.cn> Acked-by: David Hildenbrand <david@redhat.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Conor Dooley <conor.dooley@microchip.com> Cc: Conor Dooley <conor@kernel.org> Cc: Deepak Gupta <debug@rivosinc.com> Cc: Jan Kara <jack@suse.cz> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Xu <peterx@redhat.com> Cc: Rob Herring <robh@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yuanchu Xie <yuanchu@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm: softdirty: add pgtable_supports_soft_dirty()Chunyan Zhang
Patch series "mm: Add soft-dirty and uffd-wp support for RISC-V", v15. This patchset adds support for Svrsw60t59b [1] extension which is ratified now, also add soft dirty and userfaultfd write protect tracking for RISC-V. The patches 1 and 2 add macros to allow architectures to define their own checks if the soft-dirty / uffd_wp PTE bits are available, in other words for RISC-V, the Svrsw60t59b extension is supported on which device the kernel is running. Also patch1-2 are removing "ifdef CONFIG_MEM_SOFT_DIRTY" "ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP" and "ifdef CONFIG_PTE_MARKER_UFFD_WP" in favor of checks which if not overridden by the architecture, no change in behavior is expected. This patchset has been tested with kselftest mm suite in which soft-dirty, madv_populate, test_unmerge_uffd_wp, and uffd-unit-tests run and pass, and no regressions are observed in any of the other tests. This patch (of 6): Some platforms can customize the PTE PMD entry soft-dirty bit making it unavailable even if the architecture provides the resource. Add an API which architectures can define their specific implementations to detect if soft-dirty bit is available on which device the kernel is running. This patch is removing "ifdef CONFIG_MEM_SOFT_DIRTY" in favor of pgtable_supports_soft_dirty() checks that defaults to IS_ENABLED(CONFIG_MEM_SOFT_DIRTY), if not overridden by the architecture, no change in behavior is expected. We make sure to never set VM_SOFTDIRTY if !pgtable_supports_soft_dirty(), so we will never run into VM_SOFTDIRTY checks. [lorenzo.stoakes@oracle.com: fix VMA selftests] Link: https://lkml.kernel.org/r/dac6ddfe-773a-43d5-8f69-021b9ca4d24b@lucifer.local Link: https://lkml.kernel.org/r/20251113072806.795029-1-zhangchunyan@iscas.ac.cn Link: https://lkml.kernel.org/r/20251113072806.795029-2-zhangchunyan@iscas.ac.cn Link: https://github.com/riscv-non-isa/riscv-iommu/pull/543 [1] Signed-off-by: Chunyan Zhang <zhangchunyan@iscas.ac.cn> Acked-by: David Hildenbrand <david@redhat.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Conor Dooley <conor@kernel.org> Cc: Deepak Gupta <debug@rivosinc.com> Cc: Jan Kara <jack@suse.cz> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Xu <peterx@redhat.com> Cc: Rob Herring <robh@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm/vmalloc: cleanup gfp flag use in new_vmap_block()Vishal Moola (Oracle)
The only caller, vb_alloc(), passes GFP_KERNEL into new_vmap_block() which is a subset of GFP_RECLAIM_MASK. Since there's no reason to use this mask here, remove it. Link: https://lkml.kernel.org/r/20251121094405.40628-5-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Reviewed-by: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Acked-by: SeongJae Park <sj@kernel.org> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm/vmalloc: cleanup large_gfp in vm_area_alloc_pages()Vishal Moola (Oracle)
Now that we have already checked for unsupported flags, we can use the helper function to set the necessary gfp flags for the large order allocation optimization. Link: https://lkml.kernel.org/r/20251121094405.40628-4-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Reviewed-by: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Acked-by: SeongJae Park <sj@kernel.org> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm/vmalloc: add a helper to optimize vmalloc allocation gfpsVishal Moola (Oracle)
vm_area_alloc_pages() attempts to use different gfp flags as a way to optimize allocations. This has been done inline which makes things harder to read. Add a helper function to make the code more readable. Link: https://lkml.kernel.org/r/20251121094405.40628-3-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Reviewed-by: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Acked-by: SeongJae Park <sj@kernel.org> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm/vmalloc: warn on invalid vmalloc gfp flagsVishal Moola (Oracle)
Patch series "make vmalloc gfp flags usage more apparent", v4. We should do a better job at enforcing gfp flags for vmalloc. Right now, we have a kernel-doc for __vmalloc_node_range(), and hope callers pass in supported flags. If a caller were to pass in an unsupported flag, we may BUG, silently clear it, or completely ignore it. If we are more proactive about enforcing gfp flags, we can making sure callers know when they may be asking for unsupported behavior. This patchset lets vmalloc control the incoming gfp flags, and cleans up some hard to read gfp code. This patch (of 4): Vmalloc explicitly supports a list of flags, but we never enforce them. vmalloc has been trying to handle unsupported flags by clearing and setting flags wherever necessary. This is messy and makes the code harder to understand, when we could simply check for a supported input immediately instead. Define a helper mask and function telling callers they have passed in invalid flags, and clear those unsupported vmalloc flags. Link: https://lkml.kernel.org/r/20251121094405.40628-1-vishal.moola@gmail.com Link: https://lkml.kernel.org/r/20251121094405.40628-2-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Suggested-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Acked-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24memcg: remove __lruvec_stat_mod_folioShakeel Butt
__lruvec_stat_mod_folio() is already safe against irqs, so there is no need to have a separate interface (i.e. lruvec_stat_mod_folio) which wraps calls to it with irq disabling and reenabling. Let's rename __lruvec_stat_mod_folio() to lruvec_stat_mod_folio(). Link: https://lkml.kernel.org/r/20251110232008.1352063-5-shakeel.butt@linux.dev Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24memcg: remove __mod_lruvec_stateShakeel Butt
__mod_lruvec_state() is already safe against irqs, so there is no need to have a separate interface (i.e. mod_lruvec_state) which wraps calls to it with irq disabling and reenabling. Let's rename __mod_lruvec_state() to mod_lruvec_state(). Link: https://lkml.kernel.org/r/20251110232008.1352063-4-shakeel.butt@linux.dev Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24memcg: remove __mod_lruvec_kmem_stateShakeel Butt
__mod_lruvec_kmem_state() is already safe against irqs, so there is no need to have a separate interface (i.e. mod_lruvec_kmem_state) which wraps calls to it with irq disabling and reenabling. Let's rename __mod_lruvec_kmem_state() to mod_lruvec_kmem_state(). Link: https://lkml.kernel.org/r/20251110232008.1352063-3-shakeel.butt@linux.dev Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Reviewed-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24memcg: use mod_node_page_state to update statsShakeel Butt
Patch series "memcg: cleanup the memcg stats interfaces". The memcg stats are safe against irq (and nmi) context and thus does not require disabling irqs. However for some stats which are also maintained at node level, it is using irq unsafe interface and thus requiring the users to still disables irqs or use interfaces which explicitly disables irqs. Let's move memcg code to use irq safe node level stats function which is already optimized for architectures with HAVE_CMPXCHG_LOCAL (all major ones), so there will not be any performance penalty for its usage. This patch (of 4): The memcg stats are safe against irq (and nmi) context and thus does not require disabling irqs. However some code paths for memcg stats also update the node level stats and use irq unsafe interface and thus require the users to disable irqs. However node level stats, on architectures with HAVE_CMPXCHG_LOCAL (all major ones), has interface which does not require irq disabling. Let's move memcg stats code to start using that interface for node level stats. Link: https://lkml.kernel.org/r/20251110232008.1352063-1-shakeel.butt@linux.dev Link: https://lkml.kernel.org/r/20251110232008.1352063-2-shakeel.butt@linux.dev Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24selftests/mm: gup_test: fix comment regarding origin of FOLL_WRITEPeng Li
The 'FOLL_WRITE' of the copied source is located in mm_types.h of mm, not mm.h, so fix it. Link: https://lkml.kernel.org/r/20251117154012.197499-2-peng8420.li@gmail.com Signed-off-by: Peng Li <peng8420.li@gmail.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: David Hildenbrand (Red Hat) <david@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24selftests/mm: gup_test: stop testing FOLL_TOUCHPeng Li
commit 0f20bba1688b ("mm/gup: explicitly define and check internal GUP flags, disallow FOLL_TOUCH") marked FOLL_TOUCH as a GUP-internal flag. This causes a warning to fire when running gup_test, for example: $ ./gup_test -L -r 100 -z dmesg: WARNING: CPU: 1 PID: 117 at mm/gup.c:2512 is_valid_gup_args+0x66/0x8c Therefore, remove the "FOLL_TOUCH" test code from gup_test.c. Link: https://lkml.kernel.org/r/20251117154012.197499-1-peng8420.li@gmail.com Signed-off-by: Peng Li <peng8420.li@gmail.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: David Hildenbrand (Red Hat) <david@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm/huge_memory.c: introduce folio_split_unmappedBalbir Singh
Unmapped was added as a parameter to __folio_split() and related call sites to support splitting of folios already in the midst of a migration. This special case arose for device private folio migration since during migration there could be a disconnect between source and destination on the folio size. Introduce folio_split_unmapped() to handle this special case. Also refactor code and add __folio_freeze_and_split_unmapped() helper that is common to both __folio_split() and folio_split_unmapped(). This in turn removes the special casing introduced by the unmapped parameter in __folio_split(). [balbirs@nvidia.com: v2] Link: https://lkml.kernel.org/r/20251115084041.3914728-1-balbirs@nvidia.com [balbirs@nvidia.com: fix clang-20 build] Link: https://lkml.kernel.org/r/20251120134232.3588203-1-balbirs@nvidia.com [akpm@linux-foundation.org: add `inline' to shmem_uncharge() stub, per Balbir] Link: https://lkml.kernel.org/r/20251114012228.2634882-1-balbirs@nvidia.com Signed-off-by: Balbir Singh <balbirs@nvidia.com> Suggested-by: Zi Yan <ziy@nvidia.com> Acked-by: Zi Yan <ziy@nvidia.com> Cc: David Hildenbrand <david@redhat.com> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Rakie Kim <rakie.kim@sk.com> Cc: Byungchul Park <byungchul@sk.com> Cc: Gregory Price <gourry@gourry.net> Cc: Ying Huang <ying.huang@linux.alibaba.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com> Cc: Nico Pache <npache@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Barry Song <baohua@kernel.org> Cc: Lyude Paul <lyude@redhat.com> Cc: Danilo Krummrich <dakr@kernel.org> Cc: David Airlie <airlied@gmail.com> Cc: Simona Vetter <simona@ffwll.ch> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Mika Penttilä <mpenttil@redhat.com> Cc: Matthew Brost <matthew.brost@intel.com> Cc: Francois Dugast <francois.dugast@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm: shmem: allow fallback to smaller large orders for tmpfs mmap() accessBaolin Wang
After commit 69e0a3b49003 ("mm: shmem: fix the strategy for the tmpfs 'huge=' options"), we have fixed the large order allocation strategy for tmpfs, which always tries PMD-sized large folios first, and if that fails, falls back to smaller large folios. For tmpfs large folio allocation via mmap(), we should maintain the same strategy as well. Let's unify the large order allocation strategy for tmpfs. There is no functional change for large folio allocation of anonymous shmem. Link: https://lkml.kernel.org/r/283a0bdfd6ac7aa334a491422bcae70919c572bd.1763008453.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: David Hildenbrand <david@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24zram: read slot block idx under slot lockSergey Senozhatsky
Read slot's block id under slot-lock. We release the slot-lock for bdev read so, technically, slot still can get freed in the meantime, but at least we will read bdev block (page) that holds previous know slot data, not from slot->handle bdev block, which can be anything at that point. Link: https://lkml.kernel.org/r/20251122074029.3948921-7-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Brian Geffon <bgeffon@google.com> Cc: Minchan Kim <minchan@google.com> Cc: Richard Chang <richardycc@google.com> Cc: Yuwen Chen <ywen.chen@foxmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24zram: rework bdev block allocationSergey Senozhatsky
First, writeback bdev ->bitmap bits are set only from one context, as we can have only one single task performing writeback, so we cannot race with anything else. Remove retry path. Second, we always check ZRAM_WB flag to distinguish writtenback slots, so we should not confuse 0 bdev block index and 0 handle. We can use first bdev block (0 bit) for writeback as well. While at it, give functions slightly more accurate names, as we don't alloc/free anything there, we reserve a block for async writeback or release the block. Link: https://lkml.kernel.org/r/20251122074029.3948921-6-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reviewed-by: Brian Geffon <bgeffon@google.com> Cc: Minchan Kim <minchan@google.com> Cc: Richard Chang <richardycc@google.com> Cc: Yuwen Chen <ywen.chen@foxmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24zram: drop wb_limit_lockSergey Senozhatsky
We don't need wb_limit_lock. Writeback limit setters take an exclusive write zram init_lock, while wb_limit modifications happen only from a single task and under zram read init_lock. No concurrent wb_limit modifications are possible (we permit only one post-processing task at a time). Add lockdep assertions to wb_limit mutators. While at it, fixup coding styles. Link: https://lkml.kernel.org/r/20251122074029.3948921-5-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reviewed-by: Brian Geffon <bgeffon@google.com> Cc: Minchan Kim <minchan@google.com> Cc: Richard Chang <richardycc@google.com> Cc: Yuwen Chen <ywen.chen@foxmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24zram: take write lock in wb limit store handlersSergey Senozhatsky
Write device attrs handlers should take write zram init_lock. While at it, fixup coding styles. Link: https://lkml.kernel.org/r/20251122074029.3948921-4-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reviewed-by: Brian Geffon <bgeffon@google.com> Cc: Minchan Kim <minchan@google.com> Cc: Richard Chang <richardycc@google.com> Cc: Yuwen Chen <ywen.chen@foxmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24zram: add writeback batch size device attrSergey Senozhatsky
Introduce writeback_batch_size device attribute so that the maximum number of in-flight writeback bio requests can be configured at run-time per-device. This essentially enables batched bio writeback. Link: https://lkml.kernel.org/r/20251122074029.3948921-3-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reviewed-by: Brian Geffon <bgeffon@google.com> Cc: Minchan Kim <minchan@google.com> Cc: Richard Chang <richardycc@google.com> Cc: Yuwen Chen <ywen.chen@foxmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24zram: introduce writeback bio batchingSergey Senozhatsky
Patch series "zram: introduce writeback bio batching", v6. As writeback is becoming more and more common the longstanding limitations of zram writeback throughput are becoming more visible. Introduce writeback bio batching so that multiple writeback bios can be processed simultaneously. This patch (of 6): As was stated in a comment [1] a single page writeback IO is not efficient, but it works. It's time to address this throughput limitation as writeback becomes used more often. Introduce batched (multiple) bio writeback support to take advantage of parallel requests processing and better requests scheduling. Approach used in this patch doesn't use a dedicated kthread like in [2], or blk-plug like in [3]. Dedicated kthread adds complexity, which can be avoided. Apart from that not all zram setups use writeback, so having numerous per-device kthreads (on systems that create multiple zram devices) hanging around is not the most optimal thing to do. blk-plug, on the other hand, works best when request are sequential, which doesn't particularly fit zram writebck IO patterns: zram writeback IO patterns are expected to be random, due to how bdev block reservation/release are handled. blk-plug approach also works in cycles: idle IO, when zram sets up requests in a batch, is followed by bursts of IO, when zram submits the entire batch. Instead we use a batch of requests and submit new bio as soon as one of the in-flight requests completes. For the time being the writeback batch size (maximum number of in-flight bio requests) is set to 32 for all devices. A follow up patch adds a writeback_batch_size device attribute, so the batch size becomes run-time configurable. Link: https://lkml.kernel.org/r/20251122074029.3948921-1-senozhatsky@chromium.org Link: https://lkml.kernel.org/r/20251122074029.3948921-2-senozhatsky@chromium.org Link: https://lore.kernel.org/all/20181203024045.153534-6-minchan@kernel.org/ [1] Link: https://lore.kernel.org/all/20250731064949.1690732-1-richardycc@google.com/ [2] Link: https://lore.kernel.org/all/tencent_78FC2C4FE16BA1EBAF0897DB60FCD675ED05@qq.com/ [3] Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Co-developed-by: Yuwen Chen <ywen.chen@foxmail.com> Co-developed-by: Richard Chang <richardycc@google.com> Suggested-by: Minchan Kim <minchan@google.com> Cc: Brian Geffon <bgeffon@google.com> Cc: Richard Chang <richardycc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm/khugepaged: unify SCAN_PMD_NONE and SCAN_PMD_NULL into SCAN_NO_PTE_TABLEWei Yang
The current hugepage collapse scan results include two separate values, SCAN_PMD_NONE and SCAN_PMD_NULL, which are handled identically by the consuming code. To reduce confusion and improve long-term maintenance, this commit merges these two functionally equivalent states into a single, clearer identifier: SCAN_NO_PTE_TABLE Link: https://lkml.kernel.org/r/20251114030028.7035-4-richard.weiyang@gmail.com Suggested-by: "David Hildenbrand (Red Hat)" <david@kernel.org> Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Dev Jain <dev.jain@arm.com> Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Nico Pache <npache@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm/khugepaged: continue to collapse on SCAN_PMD_NONEWei Yang
SCAN_PMD_NONE means current pmd is empty, but we can still continue collapse next pmd range. Link: https://lkml.kernel.org/r/20251114030028.7035-3-richard.weiyang@gmail.com Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Lance Yang <lance.yang@linux.dev> Reviewed-by: Dev Jain <dev.jain@arm.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Cc: Barry Song <baohua@kernel.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Nico Pache <npache@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm/khugepaged: remove redundant clearing of struct collapse_controlWei Yang
Patch series "unify PMD scan results and remove redundant cleanup", v2. This small series addresses two minor cleanup opportunities in the hugepage collapse logic. The initial motivation arose during a code review of madvise_collapse(), where it was noted that the function was missing a handler for SCAN_PMD_NONE. This oversight exposed the inconsistent handling of SCAN_PMD_NULL and SCAN_PMD_NONE. Since both scan results are functionally identical (they indicate the absence of a PTE table), the primary patch unifies them into a single, clearer identifier, SCAN_NO_PTE_TABLE. The series also takes the opportunity to remove a redundant clearing of the struct collapse_control. This patch (of 3): The structure struct collapse_control is being unnecessarily cleared twice during the huge page collapse process. Both hpage_collapse_scan_file() and hpage_collapse_scan_pmd() currently perform a clear operation on this structure. Remove the redundant clear operation. Link: https://lkml.kernel.org/r/20251114030028.7035-1-richard.weiyang@gmail.com Link: https://lkml.kernel.org/r/20251114030028.7035-2-richard.weiyang@gmail.com Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Dev Jain <dev.jain@arm.com> Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Nico Pache <npache@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm: thp: reparent the split queue during memcg offlineQi Zheng
Similar to list_lru, the split queue is relatively independent and does not need to be reparented along with objcg and LRU folios (holding objcg lock and lru lock). So let's apply the similar mechanism as list_lru to reparent the split queue separately when memcg is offine. This is also a preparation for reparenting LRU folios. Link: https://lkml.kernel.org/r/8703f907c4d1f7e8a2ef2bfed3036a84fa53028b.1762762324.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Muchun Song <muchun.song@linux.dev> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nico Pache <npache@redhat.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Wei Yang <richard.weiyang@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24mm: thp: use folio_batch to handle THP splitting in deferred_split_scan()Muchun Song
The maintenance of the folio->_deferred_list is intricate because it's reused in a local list. Here are some peculiarities: 1) When a folio is removed from its split queue and added to a local on-stack list in deferred_split_scan(), the ->split_queue_len isn't updated, leading to an inconsistency between it and the actual number of folios in the split queue. 2) When the folio is split via split_folio() later, it's removed from the local list while holding the split queue lock. At this time, the lock is not needed as it is not protecting anything. 3) To handle the race condition with a third-party freeing or migrating the preceding folio, we must ensure there's always one safe (with raised refcount) folio before by delaying its folio_put(). More details can be found in commit e66f3185fa04 ("mm/thp: fix deferred split queue not partially_mapped"). It's rather tricky. We can use the folio_batch infrastructure to handle this clearly. In this case, ->split_queue_len will be consistent with the real number of folios in the split queue. If list_empty(&folio->_deferred_list) returns false, it's clear the folio must be in its split queue (not in a local list anymore). In the future, we will reparent LRU folios during memcg offline to eliminate dying memory cgroups, which requires reparenting the split queue to its parent first. So this patch prepares for using folio_split_queue_lock_irqsave() as the memcg may change then. Link: https://lkml.kernel.org/r/59cb6b6fb5ffcff9d23b81890b252960139ad8e7.1762762324.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nico Pache <npache@redhat.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Ryan Roberts <ryan.roberts@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>