linux.git/fs/nfs, branch master Linux kernel source tree Merge tag 'mm-stable-2026-08-26-15-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 2026-08-27T16:17:06+00:00 Linus Torvalds torvalds@linux-foundation.org 2026-08-27T16:17:06+00:00 18fbf5151d2c0bfe433c7428eef03cabf5fdb2fa Pull more MM updates from Andrew Morton: - "mm/rmap: index MAP_PRIVATE file-backed folios by anonymous pgoff" (Lorenzo Stoakes) Index MAP_PRIVATE file-backed folios by their anonymous page offset to resolve confusion around reverse mapping for zeroed and CoW'd file-backed memory. Use this new VMA anonymous page offset tracking to eliminate index conflicts and lay the foundation for scalable CoW performance improvements. - "promote mapped executable folios after first usage for MGLRU" (Baolin Wang) Make MGLRU's protection of mapped executable file folios more reliable. Follow the classical LRU's logic, promoting mapped executable file folios after their first usage to give executable code a better chance to stay in memory and improve workload performance. - "mm: vmscan: fix node reclaim ignoring swappiness parameter" (Ridong Chen) Fix per-node proactive reclaim interface's ignoring the swappiness parameter when CONFIG_MEMCG is disabled by consolidating sc_swappiness() into a single function that checks proactive_swappiness regardless of kernel configuration. - "mm/vmscan: reduce lru_lock contention via vmstat-derived scan-balance cost" (Usama Arif) Reduce lru_lock contention in the reclaim path by deriving scan-balance costs from vmstat counters rather than lock-acquired producer updates. Read and decay these cost signals on the reclaim side under a dedicated per-lruvec lock, reducing total LRU lock wait time by over 60% without impacting scan throughput. - "zram: fix zram issues reported by sashiko" (Sergey Senozhatsky) Fix two low-risk zram bugs which Sashiko spotted in drive-by review. - "Honor XA_FLAGS_ACCOUNT in xas_split_alloc() and charge to folio's memcg" (Zi Yan) Fix xas_split_alloc() by enabling target folio memcg charging during splits and adding the missing __GFP_ACCOUNT flag for proper XArray node memory accounting. - "selftests/mm: use pattern matching in .gitignore" (Pratyush Mallick) Replace hardcoded binary names in selftests/mm/.gitignore with a generic pattern-matching rule to automatically ignore generated test files and avoid manual updates when adding new tests. - "mm/page_ext: remove pgdat_page_ext_init()" (Sang-Heon Jeon) Make the incompatibility between FLATMEM and NUMA explicit in mm/Kconfig and remove the unused pgdat_page_ext_init() function. - "zram: fix zstd error paths and add parameter validation" (Haoqin Huang) Clean up zram compression backends by removing redundant error cleanup, adding parameter and dictionary validation, auto-prefixing algorithm error logs, and resetting parameters prior to reinitialization. - "zram: fix stale scan bounds after reinitialization" (Longlong Xia) Prevent out-of-bounds slot accesses during concurrent zram resets by moving table scan bound calculations under dev_lock in writeback_store() and read_block_state(). - "add anon mTHP collapse test cases" (Baolin Wang) Extend selftests helper functions to support arbitrary page orders and add new test cases and options for mTHP collapse in khugepaged. - "selftests/mm: Handle unsupported and transient test conditions" (Muhammad Usama Anjum) Update MM selftests to report a SKIP status instead of a failure when required kernel or filesystem features are unsupported, while adding retry logic for transient page migration errors. - "mm/zswap: Fixes and improves the zswap shrink" (Hao Jia) Fix the missing zswap global shrinker when CONFIG_MEMCG is disabled and extend shrink_memcg() to support batch writeback for improved writeback efficiency. - "alloc_tag: introduce IOCTL-based filtering for MAP" (Suren Baghdasaryan) Introduce an IOCTL-based binary interface for memory allocation profiling that enables kernel-side filtering before per-CPU counter aggregation. This eliminates the text-parsing overhead of /proc/allocinfo and provides up to a 20x speedup by transferring only filtered allocation data to userspace. - "better block swap batching and a different take on swap_ops v5" (Christoph Hellwig) Refactor block swap I/O to use swap_iocb for batching instead of single-bio requests and rebase the swap_ops interface, achieving faster swap throughput during kernel builds. - "mm: kmemleak: reduce transient false positives by confirming leaks" (Catalin Marinas) Reduce false-positive kmemleak reports by combining two kmemleak enhancements that add a second confirmation scan and a configurable minimum unreferenced scan count module parameter. - "mm: kmemleak: default min_unref_scans to 2 for verbose kernels" (Breno Leitao) Auto-scanning kernels can generate false-positive memory leak reports on single scans, so this patch defaults min_unref_scans to 2 when CONFIG_DEBUG_KMEMLEAK_VERBOSE is enabled to require a second confirming scan. - "swap_ops updates" (Christoph Hellwig) Batching I/O for synchronous swap devices causes performance regressions and filesystem-based swap suffers from double-indirection overhead. This series resolves both issues by reintroducing per-folio writes for synchronous swap and allowing filesystems to directly export their own swap_ops. - "mm/khugepaged: several cleanups" (Nico Pache) khugepaged accumulated redundant state-checking patterns and outdated comments following mTHP integration. Introduce dedicated helpers for PTE validation and event counting while refreshing the internal documentation. - "maple_tree: lock checking and clean ups" (Liam Howlett) Syzbot reports incorrectly blame memory management exit paths for locking bugs, maple tree erase operations risk allocation failures without gfp flags and internal documentation lacks clarity. Improve lock error detection, update docs, fix race and allocation edge cases and optimize erase allocations using a fallback to GFP_KERNEL | GFP_NOFAIL. * tag 'mm-stable-2026-08-26-15-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (172 commits) selftests/proc: make proc-maps-race work with READ_IMPLIES_EXEC memcg: move LRU size accounting on reparenting instead of copying it mm/vmscan: fix comment logic in balance_pgdat maple_tree: add helper mas_make_walkable() maple_tree: avoid extra gap calculation maple_tree: fix argument name in header maple_tree: change two GFP flags in tests maple_tree: document erase and allocations better maple_tree: avoid mas_erase() and mtree_erase() failures maple_tree: document that erase may use GFP_KERNEL for allocations maple_tree: catch race in mas_alloc_cyclic() maple_tree: add bulk parent set helper maple_tree: micro optimisation of mas_wr_store_type() maple_tree: optimise mas_wr_node_store() when not in rcu mode maple_tree: use prefetched value in mas_wr_store_type() maple_tree: clarify comments on mas_nomem() maple_tree: drop MAPLE_ALLOC_SLOTS maple_tree: drop dead code from mas_extend_spanning_null() maple_tree: documentation fix maple_tree: add write lock checking with lockdep sequence numbers ... 
Pull more MM updates from Andrew Morton:

 - "mm/rmap: index MAP_PRIVATE file-backed folios by anonymous pgoff"
   (Lorenzo Stoakes)

   Index MAP_PRIVATE file-backed folios by their anonymous page offset
   to resolve confusion around reverse mapping for zeroed and CoW'd
   file-backed memory.

   Use this new VMA anonymous page offset tracking to eliminate index
   conflicts and lay the foundation for scalable CoW performance
   improvements.

 - "promote mapped executable folios after first usage for MGLRU"
   (Baolin Wang)

   Make MGLRU's protection of mapped executable file folios more
   reliable. Follow the classical LRU's logic, promoting mapped
   executable file folios after their first usage to give executable
   code a better chance to stay in memory and improve workload
   performance.

 - "mm: vmscan: fix node reclaim ignoring swappiness parameter" (Ridong
   Chen)

   Fix per-node proactive reclaim interface's ignoring the swappiness
   parameter when CONFIG_MEMCG is disabled by consolidating
   sc_swappiness() into a single function that checks
   proactive_swappiness regardless of kernel configuration.

 - "mm/vmscan: reduce lru_lock contention via vmstat-derived
   scan-balance cost" (Usama Arif)

   Reduce lru_lock contention in the reclaim path by deriving
   scan-balance costs from vmstat counters rather than lock-acquired
   producer updates.

   Read and decay these cost signals on the reclaim side under a
   dedicated per-lruvec lock, reducing total LRU lock wait time by over
   60% without impacting scan throughput.

 - "zram: fix zram issues reported by sashiko" (Sergey Senozhatsky)

   Fix two low-risk zram bugs which Sashiko spotted in drive-by review.

 - "Honor XA_FLAGS_ACCOUNT in xas_split_alloc() and charge to folio's
   memcg" (Zi Yan)

   Fix xas_split_alloc() by enabling target folio memcg charging during
   splits and adding the missing __GFP_ACCOUNT flag for proper XArray
   node memory accounting.

 - "selftests/mm: use pattern matching in .gitignore" (Pratyush Mallick)

   Replace hardcoded binary names in selftests/mm/.gitignore with a
   generic pattern-matching rule to automatically ignore generated test
   files and avoid manual updates when adding new tests.

 - "mm/page_ext: remove pgdat_page_ext_init()" (Sang-Heon Jeon)

   Make the incompatibility between FLATMEM and NUMA explicit in
   mm/Kconfig and remove the unused pgdat_page_ext_init() function.

 - "zram: fix zstd error paths and add parameter validation" (Haoqin
   Huang)

   Clean up zram compression backends by removing redundant error
   cleanup, adding parameter and dictionary validation, auto-prefixing
   algorithm error logs, and resetting parameters prior to
   reinitialization.

 - "zram: fix stale scan bounds after reinitialization" (Longlong Xia)

   Prevent out-of-bounds slot accesses during concurrent zram resets by
   moving table scan bound calculations under dev_lock in
   writeback_store() and read_block_state().

 - "add anon mTHP collapse test cases" (Baolin Wang)

   Extend selftests helper functions to support arbitrary page orders
   and add new test cases and options for mTHP collapse in khugepaged.

 - "selftests/mm: Handle unsupported and transient test conditions"
   (Muhammad Usama Anjum)

   Update MM selftests to report a SKIP status instead of a failure when
   required kernel or filesystem features are unsupported, while adding
   retry logic for transient page migration errors.

 - "mm/zswap: Fixes and improves the zswap shrink" (Hao Jia)

   Fix the missing zswap global shrinker when CONFIG_MEMCG is disabled
   and extend shrink_memcg() to support batch writeback for improved
   writeback efficiency.

 - "alloc_tag: introduce IOCTL-based filtering for MAP" (Suren
   Baghdasaryan)

   Introduce an IOCTL-based binary interface for memory allocation
   profiling that enables kernel-side filtering before per-CPU counter
   aggregation.

   This eliminates the text-parsing overhead of /proc/allocinfo and
   provides up to a 20x speedup by transferring only filtered allocation
   data to userspace.

 - "better block swap batching and a different take on swap_ops v5"
   (Christoph Hellwig)

   Refactor block swap I/O to use swap_iocb for batching instead of
   single-bio requests and rebase the swap_ops interface, achieving
   faster swap throughput during kernel builds.

 - "mm: kmemleak: reduce transient false positives by confirming leaks"
   (Catalin Marinas)

   Reduce false-positive kmemleak reports by combining two kmemleak
   enhancements that add a second confirmation scan and a configurable
   minimum unreferenced scan count module parameter.

 - "mm: kmemleak: default min_unref_scans to 2 for verbose kernels"
   (Breno Leitao)

   Auto-scanning kernels can generate false-positive memory leak reports
   on single scans, so this patch defaults min_unref_scans to 2 when
   CONFIG_DEBUG_KMEMLEAK_VERBOSE is enabled to require a second
   confirming scan.

 - "swap_ops updates" (Christoph Hellwig)

   Batching I/O for synchronous swap devices causes performance
   regressions and filesystem-based swap suffers from double-indirection
   overhead. This series resolves both issues by reintroducing per-folio
   writes for synchronous swap and allowing filesystems to directly
   export their own swap_ops.

 - "mm/khugepaged: several cleanups" (Nico Pache)

   khugepaged accumulated redundant state-checking patterns and outdated
   comments following mTHP integration. Introduce dedicated helpers for
   PTE validation and event counting while refreshing the internal
   documentation.

 - "maple_tree: lock checking and clean ups" (Liam Howlett)

   Syzbot reports incorrectly blame memory management exit paths for
   locking bugs, maple tree erase operations risk allocation failures
   without gfp flags and internal documentation lacks clarity.

   Improve lock error detection, update docs, fix race and allocation
   edge cases and optimize erase allocations using a fallback to
   GFP_KERNEL | GFP_NOFAIL.

* tag 'mm-stable-2026-08-26-15-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (172 commits)
  selftests/proc: make proc-maps-race work with READ_IMPLIES_EXEC
  memcg: move LRU size accounting on reparenting instead of copying it
  mm/vmscan: fix comment logic in balance_pgdat
  maple_tree: add helper mas_make_walkable()
  maple_tree: avoid extra gap calculation
  maple_tree: fix argument name in header
  maple_tree: change two GFP flags in tests
  maple_tree: document erase and allocations better
  maple_tree: avoid mas_erase() and mtree_erase() failures
  maple_tree: document that erase may use GFP_KERNEL for allocations
  maple_tree: catch race in mas_alloc_cyclic()
  maple_tree: add bulk parent set helper
  maple_tree: micro optimisation of mas_wr_store_type()
  maple_tree: optimise mas_wr_node_store() when not in rcu mode
  maple_tree: use prefetched value in mas_wr_store_type()
  maple_tree: clarify comments on mas_nomem()
  maple_tree: drop MAPLE_ALLOC_SLOTS
  maple_tree: drop dead code from mas_extend_spanning_null()
  maple_tree: documentation fix
  maple_tree: add write lock checking with lockdep sequence numbers
  ...
Merge tag 'nfs-for-7.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs 2026-08-26T22:09:21+00:00 Linus Torvalds torvalds@linux-foundation.org 2026-08-26T22:09:21+00:00 73e3f0710014fe6d4ed98cfc02292f6121db7558 Pull NFS client updates from Trond Myklebust: "Highlights include: Stable fixes: - Use-after-free fixes for the sunrpc client code - Delegation hash table leak - NULL dereference on lockowner allocation failure - Fix a handshake completion race in the TLS code - Fix an error sign checking issue when deciding whether the pNFS layout is still in use, or can be returned - Fix a layout segment leak in pnfs_layout_process() Other bugfixes: - Fix a missing NULL check in the rpcbind client - annotate shared socket callbacks with READ_ONCE/WRITE_ONCE - nfs_inode_set_delegation() error paths should return the delegation - Use clear_and_wake_up_bit() in nfs_clear_invalid_mapping() and the pNFS code. - Fix the nfs4_alloc_client() error paths to free the IDR allocation - fix folio dereference before NULL check in nfs_inode_remove_request() - Fix delayed delegation return - Fix another state manager race with umount - Fix device leaks on parse failure - Avoid cancelling in-flight I/O during a layout recall if the server doesn't require it - flexfiles: report cancelled I/O as a layout error - flexfiles: fix NULL dereference for NFSv4.0 data servers - Fix incorrect argument passed to nfs4_delete_lease() - Fix several symlink issues resulting from nfs_atomic_open_v23() - Fix an uninitialised variable issue in the NFSv4.1 callback code - fix LAYOUTSTATS send buffer exhaustion Features and cleanups: - NFSv4.2: Allow the server to specify that file data may not be cached - localio: optimise I/O submission when when not doing memory reclaim - localio: Remove duplicate wait code in nfs_local_commit - flexfiles: support loosely coupled NFSv4.x data servers - pNFS: key the data server cache on the NFS version" * tag 'nfs-for-7.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (33 commits) NFSv4.1: fix layout segment leak on the pnfs_layout_process() forget path NFSv4/pnfs: key the data server cache on the NFS version NFSv4.2: fix LAYOUTSTATS send buffer exhaustion pNFS: Fix EBUSY check in pnfs_layout_need_return NFSv4.1: zero referring call lists before decoding nfs: fix ENXIO on O_CREAT open of existing symlink over NFSv3 SUNRPC: wait for in-flight client TLS handshake callback NFSv4: Fix incorrect argument passed to nfs4_delete_lease() in nfs4_add_lease() lockd: fix NULL dereference on lockowner allocation failure NFS: fix delegation_hash_table leak when nfs4_server_common_setup() fails NFSv4/flexfiles: support loosely coupled data servers NFSv4/flexfiles: fix NULL dereference for NFSv4.0 data servers NFSv4: pin the superblock for active state owners sunrpc: fix use-after-free in __rpc_clnt_handle_event and __rpc_clnt_remove_pipedir NFS/localio: issue commit inline when not in a memory-reclaim context NFS/localio: remove dead FLUSH_SYNC handling from nfs_local_commit NFS/localio: issue IO inline when not in a memory-reclaim context NFS: Fix delayed delegation return list handling NFS: Verify symlink inode before caching target NFS: fix folio dereference before NULL check in nfs_inode_remove_request() ... 
Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  Stable fixes:
   - Use-after-free fixes for the sunrpc client code
   - Delegation hash table leak
   - NULL dereference on lockowner allocation failure
   - Fix a handshake completion race in the TLS code
   - Fix an error sign checking issue when deciding whether the pNFS
     layout is still in use, or can be returned
   - Fix a layout segment leak in pnfs_layout_process()

  Other bugfixes:
   - Fix a missing NULL check in the rpcbind client
   - annotate shared socket callbacks with READ_ONCE/WRITE_ONCE
   - nfs_inode_set_delegation() error paths should return the delegation
   - Use clear_and_wake_up_bit() in nfs_clear_invalid_mapping() and the
     pNFS code.
   - Fix the nfs4_alloc_client() error paths to free the IDR allocation
   - fix folio dereference before NULL check in
     nfs_inode_remove_request()
   - Fix delayed delegation return
   - Fix another state manager race with umount
   - Fix device leaks on parse failure
   - Avoid cancelling in-flight I/O during a layout recall if the server
     doesn't require it
   - flexfiles: report cancelled I/O as a layout error
   - flexfiles: fix NULL dereference for NFSv4.0 data servers
   - Fix incorrect argument passed to nfs4_delete_lease()
   - Fix several symlink issues resulting from nfs_atomic_open_v23()
   - Fix an uninitialised variable issue in the NFSv4.1 callback code
   - fix LAYOUTSTATS send buffer exhaustion

  Features and cleanups:
   - NFSv4.2: Allow the server to specify that file data may not be cached
   - localio: optimise I/O submission when when not doing memory reclaim
   - localio: Remove duplicate wait code in nfs_local_commit
   - flexfiles: support loosely coupled NFSv4.x data servers
   - pNFS: key the data server cache on the NFS version"

* tag 'nfs-for-7.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (33 commits)
  NFSv4.1: fix layout segment leak on the pnfs_layout_process() forget path
  NFSv4/pnfs: key the data server cache on the NFS version
  NFSv4.2: fix LAYOUTSTATS send buffer exhaustion
  pNFS: Fix EBUSY check in pnfs_layout_need_return
  NFSv4.1: zero referring call lists before decoding
  nfs: fix ENXIO on O_CREAT open of existing symlink over NFSv3
  SUNRPC: wait for in-flight client TLS handshake callback
  NFSv4: Fix incorrect argument passed to nfs4_delete_lease() in nfs4_add_lease()
  lockd: fix NULL dereference on lockowner allocation failure
  NFS: fix delegation_hash_table leak when nfs4_server_common_setup() fails
  NFSv4/flexfiles: support loosely coupled data servers
  NFSv4/flexfiles: fix NULL dereference for NFSv4.0 data servers
  NFSv4: pin the superblock for active state owners
  sunrpc: fix use-after-free in __rpc_clnt_handle_event and __rpc_clnt_remove_pipedir
  NFS/localio: issue commit inline when not in a memory-reclaim context
  NFS/localio: remove dead FLUSH_SYNC handling from nfs_local_commit
  NFS/localio: issue IO inline when not in a memory-reclaim context
  NFS: Fix delayed delegation return list handling
  NFS: Verify symlink inode before caching target
  NFS: fix folio dereference before NULL check in nfs_inode_remove_request()
  ...
mm/swap: move swap_ops into file systems for file system-based swap 2026-08-25T01:43:20+00:00 Christoph Hellwig hch@lst.de 2026-07-23T05:46:06+00:00 22779ae8175aad7c04827db44e934e53bf2bd2d4 Currently swap to and from file systems goes through two indirect calls between the swap ops and the swap_rw method. Reduce this by directly providing the swap_ops from the file system. For this refactor swap_fs_submit into a swap_fs_prepare_rw helper that initializes the iov_iter on the callers stack so that file systems can call it directly, and use that to initialize file system specific ops in the NFS and SMB clients, which then get passed to swap_fs_activate. Link: https://lore.kernel.org/20260723054622.3460249-4-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Chris Li <chrisl@kernel.org> Cc: Baoquan He <baoquan.he@linux.dev> Cc: Kairui Song <kasong@tencent.com> Cc: Kairui Song <ryncsn@gmail.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Steve French <sfrench@samba.org> Cc: Usama Arif <usama.arif@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> 
Currently swap to and from file systems goes through two indirect calls
between the swap ops and the swap_rw method.  Reduce this by directly
providing the swap_ops from the file system.

For this refactor swap_fs_submit into a swap_fs_prepare_rw helper that
initializes the iov_iter on the callers stack so that file systems can
call it directly, and use that to initialize file system specific ops in
the NFS and SMB clients, which then get passed to swap_fs_activate.

Link: https://lore.kernel.org/20260723054622.3460249-4-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Chris Li <chrisl@kernel.org>
Cc: Baoquan He <baoquan.he@linux.dev>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kairui Song <ryncsn@gmail.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Steve French <sfrench@samba.org>
Cc: Usama Arif <usama.arif@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mm/swap: remove SWP_FS_OPS 2026-08-25T01:43:15+00:00 Christoph Hellwig hch@lst.de 2026-07-13T09:33:43+00:00 0df74c11587941b35596d1e8990dcab06bdbfeb5 Provide a swap_fs_activate helper that directly sets up swap_fs_ops, and a flag in struct swap_ops to indicate of NOFS swapping is allowed. Link: https://lore.kernel.org/20260713093350.2154226-7-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <baoquan.he@linux.dev> 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> Cc: Youngjun Park <youngjun.park@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> 
Provide a swap_fs_activate helper that directly sets up swap_fs_ops, and a
flag in struct swap_ops to indicate of NOFS swapping is allowed.

Link: https://lore.kernel.org/20260713093350.2154226-7-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <baoquan.he@linux.dev>
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>
Cc: Youngjun Park <youngjun.park@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
NFSv4.1: fix layout segment leak on the pnfs_layout_process() forget path 2026-08-20T22:18:20+00:00 Junrui Luo moonafterrain@outlook.com 2026-08-16T08:01:29+00:00 ee5a386cfe60f3f8286de16a9db8e1a08f0bc124 When the server returns a new layout stateid while a valid one is still held, pnfs_layout_process() calls pnfs_mark_matching_lsegs_return() on the on-stack free_me list and jumps to out_forget. Segments whose reference count drops to zero are unlinked from lo->plh_segs and moved to free_me by mark_lseg_invalid(); for an idle cached segment the layout header holds the only reference, so this happens on the first decrement. out_forget never drains free_me -- only the success path calls pnfs_free_lseg_list(). Commit 814b84971388 ("pNFS/NFSv4: Fix a layout segment leak in pnfs_layout_process()") added the drain; commit 08bd8dbe8882 ("pNFS/NFSv4: Try to return invalid layout in pnfs_layout_process()") removed it while switching the destination to lo->plh_return_segs, which is drained elsewhere. Commit fb700ef02676 ("NFSv4.1: Simplify layout return in pnfs_layout_process()") switched the destination back to free_me without restoring the drain. Restore the pnfs_free_lseg_list() call. Fixes: fb700ef02676 ("NFSv4.1: Simplify layout return in pnfs_layout_process()") Reported-by: Yuhao Jiang <danisjiang@gmail.com> Assisted-by: Claude:claude-opus-5 Cc: stable@vger.kernel.org Signed-off-by: Junrui Luo <moonafterrain@outlook.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> 
When the server returns a new layout stateid while a valid one is still
held, pnfs_layout_process() calls pnfs_mark_matching_lsegs_return() on
the on-stack free_me list and jumps to out_forget. Segments whose
reference count drops to zero are unlinked from lo->plh_segs and moved
to free_me by mark_lseg_invalid(); for an idle cached segment the layout
header holds the only reference, so this happens on the first decrement.

out_forget never drains free_me -- only the success path calls
pnfs_free_lseg_list().

Commit 814b84971388 ("pNFS/NFSv4: Fix a layout segment leak in
pnfs_layout_process()") added the drain; commit 08bd8dbe8882
("pNFS/NFSv4: Try to return invalid layout in pnfs_layout_process()")
removed it while switching the destination to lo->plh_return_segs, which
is drained elsewhere. Commit fb700ef02676 ("NFSv4.1: Simplify layout
return in pnfs_layout_process()") switched the destination back to
free_me without restoring the drain.

Restore the pnfs_free_lseg_list() call.

Fixes: fb700ef02676 ("NFSv4.1: Simplify layout return in pnfs_layout_process()")
Reported-by: Yuhao Jiang <danisjiang@gmail.com>
Assisted-by: Claude:claude-opus-5
Cc: stable@vger.kernel.org
Signed-off-by: Junrui Luo <moonafterrain@outlook.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
NFSv4/pnfs: key the data server cache on the NFS version 2026-08-20T22:18:20+00:00 Junrui Luo moonafterrain@outlook.com 2026-08-16T08:01:28+00:00 13c23c5cb977f66390795437fd3837887ce1fd75 nfs4_pnfs_ds_add() keys the per-net data server cache on the multipath address set alone, and struct nfs4_pnfs_ds records no version. That suffices for the files layout driver, which always connects with version 4, but flexfiles takes its version tuple from GETDEVICEINFO per device, and one address can legitimately serve both NFSv3 and NFSv4. Two deviceids on one address with different ds_versions[0].version therefore share a single nfs4_pnfs_ds, and whichever mirror connects first pins ds_clp to its own version. The other one is handed that client anyway, so it selects rpc_call_ops for a version the connection does not speak, and the mismatched sequence-slot handling dereferences NULL. Add the version to the cache key so the two cannot alias, giving each version its own nfs4_pnfs_ds and connection while both mirrors stay usable. Only the major version is compared, since that is what selects rpc_call_ops and rpc_ops; v4.0 and v4.1 keep sharing a client. The files layout driver passes the 4 it already hardcodes at connect time. Fixes: d67ae825a59d ("pnfs/flexfiles: Add the FlexFile Layout Driver") Reported-by: Yuhao Jiang <danisjiang@gmail.com> Assisted-by: Claude:claude-opus-5 Signed-off-by: Junrui Luo <moonafterrain@outlook.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> 
nfs4_pnfs_ds_add() keys the per-net data server cache on the multipath
address set alone, and struct nfs4_pnfs_ds records no version. That
suffices for the files layout driver, which always connects with version
4, but flexfiles takes its version tuple from GETDEVICEINFO per device,
and one address can legitimately serve both NFSv3 and NFSv4.

Two deviceids on one address with different ds_versions[0].version
therefore share a single nfs4_pnfs_ds, and whichever mirror connects
first pins ds_clp to its own version. The other one is handed that
client anyway, so it selects rpc_call_ops for a version the connection
does not speak, and the mismatched sequence-slot handling dereferences
NULL.

Add the version to the cache key so the two cannot alias, giving each
version its own nfs4_pnfs_ds and connection while both mirrors stay
usable. Only the major version is compared, since that is what selects
rpc_call_ops and rpc_ops; v4.0 and v4.1 keep sharing a client. The files
layout driver passes the 4 it already hardcodes at connect time.

Fixes: d67ae825a59d ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Reported-by: Yuhao Jiang <danisjiang@gmail.com>
Assisted-by: Claude:claude-opus-5
Signed-off-by: Junrui Luo <moonafterrain@outlook.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
pNFS: Fix EBUSY check in pnfs_layout_need_return 2026-08-20T22:18:20+00:00 Tim Menninger tmenninger@everpuredata.com 2026-08-19T12:41:21+00:00 20358201777496fd0bb7b4336fcb4d3fc13cad28 Commit 41d0a8ead9720 ("NFSv4/pnfs: Add support for the PNFS_LAYOUT_FILE_BULK_RETURN flag") replaced pnfs_layout_segments_returnable() in pnfs_layout_need_return() with a direct call to pnfs_mark_layout_stateid_return(). The old helper checked the return value against -EBUSY, but the replacement compares against EBUSY. Since pnfs_mark_layout_stateid_return() returns negative errno values, the -EBUSY case is never detected. Fix the comparison in pnfs_layout_need_return() to check against -EBUSY. Fixes: 41d0a8ead9720 ("NFSv4/pnfs: Add support for the PNFS_LAYOUT_FILE_BULK_RETURN flag") Cc: stable@vger.kernel.org Signed-off-by: Tim Menninger <tmenninger@everpuredata.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> 
Commit 41d0a8ead9720 ("NFSv4/pnfs: Add support for the
PNFS_LAYOUT_FILE_BULK_RETURN flag") replaced
pnfs_layout_segments_returnable() in pnfs_layout_need_return() with a
direct call to pnfs_mark_layout_stateid_return().

The old helper checked the return value against -EBUSY, but the
replacement compares against EBUSY. Since
pnfs_mark_layout_stateid_return() returns negative errno values, the
-EBUSY case is never detected.

Fix the comparison in pnfs_layout_need_return() to check against -EBUSY.

Fixes: 41d0a8ead9720 ("NFSv4/pnfs: Add support for the PNFS_LAYOUT_FILE_BULK_RETURN flag")
Cc: stable@vger.kernel.org
Signed-off-by: Tim Menninger <tmenninger@everpuredata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
NFSv4.1: zero referring call lists before decoding 2026-08-20T21:51:53+00:00 Jérémy Jean Jeremy.Jean@oss.cyber.gouv.fr 2026-08-20T20:53:29+00:00 8fa4804fe62ca4155a2d8fc2789d630376cbf2fc decode_cb_sequence_args() allocates csa_rclists with kmalloc_objs(), so each referring_call_list starts uninitialized. decode_rc_list() assigns rcl_refcalls only when rcl_nrefcalls is nonzero. A valid list with zero referring calls therefore leaves the pointer uninitialized, and nfs4_callback_sequence() later passes stale slab contents to kfree(). Allocate csa_rclists with kzalloc_objs() so every rcl_refcalls member is NULL from the beginning, including valid empty referring call lists. Fixes: 4aece6a19cf7 ("nfs41: cb_sequence xdr implementation") Assisted-by: Codex:gpt-5 Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> 
decode_cb_sequence_args() allocates csa_rclists with kmalloc_objs(), so
each referring_call_list starts uninitialized. decode_rc_list() assigns
rcl_refcalls only when rcl_nrefcalls is nonzero. A valid list with zero
referring calls therefore leaves the pointer uninitialized, and
nfs4_callback_sequence() later passes stale slab contents to kfree().

Allocate csa_rclists with kzalloc_objs() so every rcl_refcalls member is
NULL from the beginning, including valid empty referring call lists.

Fixes: 4aece6a19cf7 ("nfs41: cb_sequence xdr implementation")
Assisted-by: Codex:gpt-5
Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Merge tag 'nfsd-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux 2026-08-20T19:39:56+00:00 Linus Torvalds torvalds@linux-foundation.org 2026-08-20T19:39:56+00:00 d141ec2825b4d3ec52f27c43bdd864090159273a Pull nfsd updates from Chuck Lever: - CB_NOTIFY support for NFSD's NFSv4.1 directory delegations The server used to recall a delegation as soon as the directory changed. NFSD now watches delegated directories through fsnotify and reports adds, removes, renames, and directory attribute changes, carrying the filehandle and attributes of the affected entry, so clients can keep their caches. Some of the NOTIFY4 flags come from RFC 8881bis (Jeff Layton) - Continued netlink work A new server-stats-get operation reports what /proc/net/rpc/nfsd publishes, plus NFSv4 callback counts, and SUNRPC now keeps its per-procedure call counts per network namespace, so a container sees its own numbers. nfsstat reads all of this over netlink, with a procfs fallback for older kernels (Jeff Layton) - Remove SUNRPC service thread pool mode selection Per node is the right choice on any host we run today, so the auto, global, and percpu modes have been removed. A single-node host still gets one pool. A multi-NUMA host now gets a pool per node. sunrpc.pool_mode accepts the old names but no longer selects anything. - Bug fixes, clean-ups, and small optimizations: - async COPY offload rework (Jeff Layton) - more use-after-free fixes in the NFSv4 state revocation paths - percpu counter contention removed from the reply cache and IO accounting - a long list of hardening fixes (Chris Mason) Sincere thanks to all contributors, reviewers, testers, and bug reporters who participated in the v7.3 NFSD development cycle. * tag 'nfsd-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (182 commits) nfsd: export NFSv4 callback op stats via netlink nfsd: count NFSv4 callback operations per netns sunrpc: remove unused svc_version vs_count field nfsd: implement server-stats-get netlink handler sunrpc: use per-net counts in svc_seq_show() sunrpc: add per-netns per-procedure call counts to svc_stat NFSD: Document reply_cache_stats ABI NFSD: Eliminate percpu counter contention in IO byte accounting NFSD: Eliminate percpu counter contention in reply cache statistics NFSD: Eliminate percpu counter contention in DRC memory accounting NFSD: Fix off-by-one in DRC bucket pruning limit NFSD: Relocate NFSv4 "supported attributes" to new header NFSD: Relocate nfsd4_set_netaddr() NFSD: Relocate nfsd_user_namespace() NFSD: Move struct readdir_cd NFSD: Move the export.h include from nfsd.h to auth.c NFSD: Remove '#include "nfsd.h"' from fs/nfsd/cache.h NFSD: include "netns.h" NFSD: Explicitly include "stats.h" NFSD: Make "stats.h" self-contained ... 
Pull nfsd updates from Chuck Lever:

 - CB_NOTIFY support for NFSD's NFSv4.1 directory delegations

   The server used to recall a delegation as soon as the directory
   changed. NFSD now watches delegated directories through fsnotify and
   reports adds, removes, renames, and directory attribute changes,
   carrying the filehandle and attributes of the affected entry, so
   clients can keep their caches. Some of the NOTIFY4 flags come from
   RFC 8881bis (Jeff Layton)

 - Continued netlink work

   A new server-stats-get operation reports what /proc/net/rpc/nfsd
   publishes, plus NFSv4 callback counts, and SUNRPC now keeps its
   per-procedure call counts per network namespace, so a container sees
   its own numbers. nfsstat reads all of this over netlink, with a
   procfs fallback for older kernels (Jeff Layton)

 - Remove SUNRPC service thread pool mode selection

   Per node is the right choice on any host we run today, so the auto,
   global, and percpu modes have been removed. A single-node host still
   gets one pool. A multi-NUMA host now gets a pool per node.

   sunrpc.pool_mode accepts the old names but no longer selects
   anything.

 - Bug fixes, clean-ups, and small optimizations:
    - async COPY offload rework (Jeff Layton)
    - more use-after-free fixes in the NFSv4 state revocation paths
    - percpu counter contention removed from the reply cache and IO
      accounting
    - a long list of hardening fixes (Chris Mason)

Sincere thanks to all contributors, reviewers, testers, and bug
reporters who participated in the v7.3 NFSD development cycle.

* tag 'nfsd-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (182 commits)
  nfsd: export NFSv4 callback op stats via netlink
  nfsd: count NFSv4 callback operations per netns
  sunrpc: remove unused svc_version vs_count field
  nfsd: implement server-stats-get netlink handler
  sunrpc: use per-net counts in svc_seq_show()
  sunrpc: add per-netns per-procedure call counts to svc_stat
  NFSD: Document reply_cache_stats ABI
  NFSD: Eliminate percpu counter contention in IO byte accounting
  NFSD: Eliminate percpu counter contention in reply cache statistics
  NFSD: Eliminate percpu counter contention in DRC memory accounting
  NFSD: Fix off-by-one in DRC bucket pruning limit
  NFSD: Relocate NFSv4 "supported attributes" to new header
  NFSD: Relocate nfsd4_set_netaddr()
  NFSD: Relocate nfsd_user_namespace()
  NFSD: Move struct readdir_cd
  NFSD: Move the export.h include from nfsd.h to auth.c
  NFSD: Remove '#include "nfsd.h"' from fs/nfsd/cache.h
  NFSD: include "netns.h"
  NFSD: Explicitly include "stats.h"
  NFSD: Make "stats.h" self-contained
  ...
Merge tag 'vfs-7.3-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs 2026-08-17T19:56:12+00:00 Linus Torvalds torvalds@linux-foundation.org 2026-08-17T19:56:12+00:00 1c3e8cef79ea5f1415cff0d3c507e2e07b71ade8 Pull misc vfs updates from Christian Brauner: "Bigger cleanups: - The lockref dead-count handling is tidied up. The open-coded check for a count below zero as the dead marker relies on information the caller should not have. - make put_mnt_ns() leave mounts connected. Destroying a mount namespace disconnected its mounts from their mount points. So a file descriptor still open on the parent of a mount point could be used to peek under it. Locked mounts were already kept connected to prevent exactly that. But a mount is only locked when its tree is copied across a user namespace boundary. So a mount namespace set up by a privileged component had no locked mounts and its mounts were disconnected. Passing UMOUNT_CONNECTED keeps every mount connected and prevents that bug. - vfs_prepare_mode() passes S_IFDIR for directories. I meant to fix that ago but didn't get to it. So now someone finally did it. This kills the exception where the mode could be 0 when a directory was created whereas every other creation operation passed it explicitly already. - move long delayed work for ufs, jffs2, hfsplus, hfs and affs from the per-cpu system_long_wq to the new unbound system_dfl_long_wq. None of that work relies on per-cpu state and the work item is enqueued with queue_delayed_work() whose timer is global anyway. So it may as well benefit from scheduler task placement. Smaller fixes and cleanups: - unlock_buffer() and journal_end_buffer_io_sync() use clear_and_wake_up_bit() - the pipe page pools are unified into a single per-pipe pool and the extra wake_up(rd_wait) is limited to EPOLLET consumers - eventpoll now computes its timer slack lazily in ep_poll() - shrink_dcache_for_umount() keeps making progress on busy roots - excess xarray nodes are freed in clear_inode() - romfs detects hard link cycles - the user path of nested backing files is fixed - pidfd holds exec_update_lock around the namespace ioctl - non-memcg-aware nr_cached_objects is skipped during memcg slab shrink - iomap_write_iter() always returns status - mangle_path() is renamed to seq_mangle_path() - inode timestamp accessors are annotated - new regression test for pipe->poll_usage. - a few documentation, kernel-doc and selftest fixes" * tag 'vfs-7.3-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (67 commits) selftests/namespaces: Fix racy pipe handshake in timens and pidns_separate selftests/epoll: add a regression test for pipe->poll_usage pipe: only enable the extra wake_up(rd_wait) for EPOLLET consumers pidfd: hold exec_update_lock around namespace ioctl fs: fix user path of nested backing files fs: remove stale inode_insert5() kernel-doc parameter fs: fix switch/case indentation in sysfs() syscall fs: document semantics of kstat::{uid,gid} fields dcache: keep shrink_dcache_for_umount() making progress on busy roots seq_file: rename mangle_path to seq_mangle_path nstree: add/fix struct ns_id_req kernel-doc member fields dcache: use lockref routines for dead count checks lockref: tidy up dead count handling initramfs: fix typo in reserve_initrd_mem comment fs/pipe: unify the page pools into a single per-pipe pool fs: annotate inode timestamp accessors eventpoll: compute timer slack lazily in ep_poll() selftests/filesystems: add mntns cleanup test put_mnt_ns(): leave mounts connected affs: Move long delayed work on system_dfl_long_wq ... 
Pull misc vfs updates from Christian Brauner:
 "Bigger cleanups:

   - The lockref dead-count handling is tidied up.

     The open-coded check for a count below zero as the dead marker
     relies on information the caller should not have.

   - make put_mnt_ns() leave mounts connected. Destroying a mount
     namespace disconnected its mounts from their mount points. So a
     file descriptor still open on the parent of a mount point could be
     used to peek under it.

     Locked mounts were already kept connected to prevent exactly that.
     But a mount is only locked when its tree is copied across a user
     namespace boundary. So a mount namespace set up by a privileged
     component had no locked mounts and its mounts were disconnected.
     Passing UMOUNT_CONNECTED keeps every mount connected and prevents
     that bug.

   - vfs_prepare_mode() passes S_IFDIR for directories. I meant to fix
     that ago but didn't get to it. So now someone finally did it.

     This kills the exception where the mode could be 0 when a directory
     was created whereas every other creation operation passed it
     explicitly already.

   - move long delayed work for ufs, jffs2, hfsplus, hfs and affs from
     the per-cpu system_long_wq to the new unbound system_dfl_long_wq.

     None of that work relies on per-cpu state and the work item is
     enqueued with queue_delayed_work() whose timer is global anyway. So
     it may as well benefit from scheduler task placement.

  Smaller fixes and cleanups:

   - unlock_buffer() and journal_end_buffer_io_sync() use
     clear_and_wake_up_bit()

   - the pipe page pools are unified into a single per-pipe pool and the
     extra wake_up(rd_wait) is limited to EPOLLET consumers

   - eventpoll now computes its timer slack lazily in ep_poll()

   - shrink_dcache_for_umount() keeps making progress on busy roots

   - excess xarray nodes are freed in clear_inode()

   - romfs detects hard link cycles

   - the user path of nested backing files is fixed

   - pidfd holds exec_update_lock around the namespace ioctl

   - non-memcg-aware nr_cached_objects is skipped during memcg slab
     shrink

   - iomap_write_iter() always returns status

   - mangle_path() is renamed to seq_mangle_path()

   - inode timestamp accessors are annotated

   - new regression test for pipe->poll_usage.

   - a few documentation, kernel-doc and selftest fixes"

* tag 'vfs-7.3-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (67 commits)
  selftests/namespaces: Fix racy pipe handshake in timens and pidns_separate
  selftests/epoll: add a regression test for pipe->poll_usage
  pipe: only enable the extra wake_up(rd_wait) for EPOLLET consumers
  pidfd: hold exec_update_lock around namespace ioctl
  fs: fix user path of nested backing files
  fs: remove stale inode_insert5() kernel-doc parameter
  fs: fix switch/case indentation in sysfs() syscall
  fs: document semantics of kstat::{uid,gid} fields
  dcache: keep shrink_dcache_for_umount() making progress on busy roots
  seq_file: rename mangle_path to seq_mangle_path
  nstree: add/fix struct ns_id_req kernel-doc member fields
  dcache: use lockref routines for dead count checks
  lockref: tidy up dead count handling
  initramfs: fix typo in reserve_initrd_mem comment
  fs/pipe: unify the page pools into a single per-pipe pool
  fs: annotate inode timestamp accessors
  eventpoll: compute timer slack lazily in ep_poll()
  selftests/filesystems: add mntns cleanup test
  put_mnt_ns(): leave mounts connected
  affs: Move long delayed work on system_dfl_long_wq
  ...