2618 Commits
Author SHA1 Message Date
Hristo Venev 544576f0f0 ceph: put folios not suitable for writeback
The batch holds references to the folios (see `filemap_get_folios`,
`folio_batch_release`), so we need to `folio_put` the folios we remove.

Tested on v6.18.

Cc: stable@vger.kernel.org
Link: https://tracker.ceph.com/issues/74156
Signed-off-by: Hristo Venev <hristo@venev.name>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-05-11 10:39:22 +02:00
Viacheslav Dubeyko 10d9be4011 ceph: add ceph_has_realms_with_quotas() check to ceph_quota_update_statfs()
When MDS rejects a session, remove_session_caps() ->
__ceph_remove_cap() -> ceph_change_snap_realm() clears
i_snap_realm for every inode that loses its last cap.
The realm is restored once caps are re-granted after
reconnect. It is not a real error and this patch changes
pr_err_ratelimited_client() on doutc().

Every quota methods ceph_quota_is_max_files_exceeded(),
ceph_quota_is_max_bytes_exceeded(),
ceph_quota_is_max_bytes_approaching() calls
ceph_has_realms_with_quotas() check. This patch adds
the missing ceph_has_realms_with_quotas() call into
ceph_quota_update_statfs().

[ idryomov: add braces around both arms of multiline ifs ]

Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Alex Markuze <amarkuze@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-05-11 10:39:22 +02:00
Viacheslav Dubeyko 0c22d9511c ceph: fix BUG_ON in __ceph_build_xattrs_blob() due to stale blob size
The generic/642 test-case can reproduce the kernel crash:

[40243.605254] ------------[ cut here ]------------
[40243.605956] kernel BUG at fs/ceph/xattr.c:918!
[40243.607142] Oops: invalid opcode: 0000 [#1] SMP PTI
[40243.608067] CPU: 7 UID: 0 PID: 498762 Comm: kworker/7:1 Not tainted 7.0.0-rc7+ #3 PREEMPT(full)
[40243.609700] Hardware name: QEMU Ubuntu 25.10 PC v2 (i440FX + PIIX, + 10.1 machine, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[40243.611820] Workqueue: ceph-msgr ceph_con_workfn
[40243.612715] RIP: 0010:__ceph_build_xattrs_blob+0x1b8/0x1e0
[40243.613731] Code: 0f 84 82 fe ff ff e9 cf 8e 56 ff 48 8d 65 e8 31 c0 5b 41 5c 41 5d 5d 31 d2 31 c9 31 f6 31 ff 45 31 c0 45 31 c9 c3 cc cc cc cc <0f> 0b 4c 8b 62 08 41 8b 85 24 07 00 00 49 83 c4 04 41 89 44 24 fc
[40243.616888] RSP: 0018:ffffcc80c4d4b688 EFLAGS: 00010287
[40243.617773] RAX: 0000000000010026 RBX: 0000000000000001 RCX: 0000000000000000
[40243.618928] RDX: ffff8a773798dee0 RSI: 0000000000000000 RDI: 0000000000000000
[40243.620158] RBP: ffffcc80c4d4b6a0 R08: 0000000000000000 R09: 0000000000000000
[40243.621573] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8a75f3b58000
[40243.622907] R13: ffff8a75f3b58000 R14: 0000000000000080 R15: 000000000000bffd
[40243.624054] FS:  0000000000000000(0000) GS:ffff8a787d1b4000(0000) knlGS:0000000000000000
[40243.625331] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[40243.626269] CR2: 000072f390b623c0 CR3: 000000011c02a003 CR4: 0000000000372ef0
[40243.627408] Call Trace:
[40243.627839]  <TASK>
[40243.628188]  __prep_cap+0x3fd/0x4a0
[40243.628789]  ? do_raw_spin_unlock+0x4e/0xe0
[40243.629474]  ceph_check_caps+0x46a/0xc80
[40243.630094]  ? __lock_acquire+0x4a2/0x2650
[40243.630773]  ? find_held_lock+0x31/0x90
[40243.631347]  ? handle_cap_grant+0x79f/0x1060
[40243.632068]  ? lock_release+0xd9/0x300
[40243.632696]  ? __mutex_unlock_slowpath+0x3e/0x340
[40243.633429]  ? lock_release+0xd9/0x300
[40243.634052]  handle_cap_grant+0xcf6/0x1060
[40243.634745]  ceph_handle_caps+0x122b/0x2110
[40243.635415]  mds_dispatch+0x5bd/0x2160
[40243.636034]  ? ceph_con_process_message+0x65/0x190
[40243.636828]  ? lock_release+0xd9/0x300
[40243.637431]  ceph_con_process_message+0x7a/0x190
[40243.638184]  ? kfree+0x311/0x4f0
[40243.638749]  ? kfree+0x311/0x4f0
[40243.639268]  process_message+0x16/0x1a0
[40243.639915]  ? sg_free_table+0x39/0x90
[40243.640572]  ceph_con_v2_try_read+0xf58/0x2120
[40243.641255]  ? lock_acquire+0xc8/0x300
[40243.641863]  ceph_con_workfn+0x151/0x820
[40243.642493]  process_one_work+0x22f/0x630
[40243.643093]  ? process_one_work+0x254/0x630
[40243.643770]  worker_thread+0x1e2/0x400
[40243.644332]  ? __pfx_worker_thread+0x10/0x10
[40243.645020]  kthread+0x109/0x140
[40243.645560]  ? __pfx_kthread+0x10/0x10
[40243.646125]  ret_from_fork+0x3f8/0x480
[40243.646752]  ? __pfx_kthread+0x10/0x10
[40243.647316]  ? __pfx_kthread+0x10/0x10
[40243.647919]  ret_from_fork_asm+0x1a/0x30
[40243.648556]  </TASK>
[40243.648902] Modules linked in: overlay hctr2 libpolyval chacha libchacha adiantum libnh libpoly1305 essiv intel_rapl_msr intel_rapl_common intel_uncore_frequency_common skx_edac_common nfit kvm_intel kvm irqbypass joydev ghash_clmulni_intel aesni_intel rapl input_leds mac_hid psmouse vga16fb serio_raw vgastate floppy i2c_piix4 pata_acpi bochs qemu_fw_cfg i2c_smbus sch_fq_codel rbd dm_crypt msr parport_pc ppdev lp parport efi_pstore
[40243.654766] ---[ end trace 0000000000000000 ]---

Commit d93231a6bc ("ceph: prevent a client from exceeding the MDS
maximum xattr size") moved the required_blob_size computation to before
the __build_xattrs() call, introducing a race.

__build_xattrs() releases and reacquires i_ceph_lock during execution.
In that window, handle_cap_grant() may update i_xattrs.blob with a
newer MDS-provided blob and bump i_xattrs.version.  When
__build_xattrs() detects that index_version < version, it destroys and
rebuilds the entire xattr rb-tree from the new blob, potentially
increasing count, names_size, and vals_size.

The prealloc_blob size check that follows still uses the stale
required_blob_size computed before the rebuild, so it passes even when
prealloc_blob is too small for the now-larger tree. After __set_xattr()
adds one more xattr on top, __ceph_build_xattrs_blob() is called from
the cap flush path and hits:

    BUG_ON(need > ci->i_xattrs.prealloc_blob->alloc_len);

Fix this by recomputing required_blob_size after __build_xattrs()
returns, using the current tree state. Also re-validate against
m_max_xattr_size to fall back to the sync path if the rebuilt tree now
exceeds the MDS limit.

Cc: stable@vger.kernel.org
Fixes: d93231a6bc ("ceph: prevent a client from exceeding the MDS maximum xattr size")
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Alex Markuze <amarkuze@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-05-11 10:39:22 +02:00
Viacheslav Dubeyko 5d3cc36b4e ceph: fix a buffer leak in __ceph_setxattr()
The old_blob in __ceph_setxattr() can store
ci->i_xattrs.prealloc_blob value during the retry.
However, it is never called the ceph_buffer_put()
for the old_blob object. This patch fixes the issue of
the buffer leak.

Cc: stable@vger.kernel.org
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Alex Markuze <amarkuze@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-05-11 10:39:22 +02:00
Linus Torvalds ac2dc6d574 Merge tag 'ceph-for-7.1-rc1' of https://github.com/ceph/ceph-client
Pull ceph updates from Ilya Dryomov:
 "We have a series from Alex which extends CephFS client metrics with
  support for per-subvolume data I/O performance and latency tracking
  (metadata operations aren't included) and a good variety of fixes and
  cleanups across RBD and CephFS"

* tag 'ceph-for-7.1-rc1' of https://github.com/ceph/ceph-client:
  ceph: add subvolume metrics collection and reporting
  ceph: parse subvolume_id from InodeStat v9 and store in inode
  ceph: handle InodeStat v8 versioned field in reply parsing
  libceph: Fix slab-out-of-bounds access in auth message processing
  rbd: fix null-ptr-deref when device_add_disk() fails
  crush: cleanup in crush_do_rule() method
  ceph: clear s_cap_reconnect when ceph_pagelist_encode_32() fails
  ceph: only d_add() negative dentries when they are unhashed
  libceph: update outdated comment in ceph_sock_write_space()
  libceph: Remove obsolete session key alignment logic
  ceph: fix num_ops off-by-one when crypto allocation fails
  libceph: Prevent potential null-ptr-deref in ceph_handle_auth_reply()
2026-04-24 13:47:19 -07:00
Alex Markuze b1137e0b3d ceph: add subvolume metrics collection and reporting
Add complete infrastructure for per-subvolume I/O metrics collection
and reporting to the MDS. This enables administrators to monitor I/O
patterns at the subvolume granularity, which is useful for multi-tenant
CephFS deployments.

This patch adds:
- CEPHFS_FEATURE_SUBVOLUME_METRICS feature flag for MDS negotiation
- CEPH_SUBVOLUME_ID_NONE constant (0) for unknown/unset state
- Red-black tree based metrics tracker for efficient per-subvolume
  aggregation with kmem_cache for entry allocations
- Wire format encoding matching the MDS C++ AggregatedIOMetrics struct
- Integration with the existing CLIENT_METRICS message
- Recording of I/O operations from file read/write and writeback paths
- Debugfs interfaces for monitoring (metrics/subvolumes, metrics/metric_features)

Metrics tracked per subvolume include:
- Read/write operation counts
- Read/write byte counts
- Read/write latency sums (for average calculation)

The metrics are periodically sent to the MDS as part of the existing
metrics reporting infrastructure when the MDS advertises support for
the SUBVOLUME_METRICS feature.

CEPH_SUBVOLUME_ID_NONE enforces subvolume_id immutability. Following
the FUSE client convention, 0 means unknown/unset. Once an inode has
a valid (non-zero) subvolume_id, it should not change during the
inode's lifetime.

Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-04-22 01:40:23 +02:00
Alex Markuze 4a1c543479 ceph: parse subvolume_id from InodeStat v9 and store in inode
Add support for parsing the subvolume_id field from InodeStat v9 and
storing it in the inode for later use by subvolume metrics tracking.

The subvolume_id identifies which CephFS subvolume an inode belongs to,
enabling per-subvolume I/O metrics collection and reporting.

This patch:
- Adds subvolume_id field to struct ceph_mds_reply_info_in
- Adds i_subvolume_id field to struct ceph_inode_info
- Parses subvolume_id from v9 InodeStat in parse_reply_info_in()
- Adds ceph_inode_set_subvolume() helper to propagate the ID to inodes
- Initializes i_subvolume_id in inode allocation and clears on destroy

Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-04-22 01:40:23 +02:00
Alex Markuze e58103caff ceph: handle InodeStat v8 versioned field in reply parsing
Add forward-compatible handling for the new versioned field introduced
in InodeStat v8. This patch only skips the field without using it,
preparing for future protocol extensions.

The v8 encoding adds a versioned sub-structure that needs to be properly
decoded and skipped to maintain compatibility with newer MDS versions.

Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-04-22 01:40:23 +02:00
Max Kellermann cc56430954 ceph: clear s_cap_reconnect when ceph_pagelist_encode_32() fails
This MDS reconnect error path leaves s_cap_reconnect set.
send_mds_reconnect() sets the bit at the beginning of the reconnect,
but the first failing operation after that, ceph_pagelist_encode_32(),
can jump to `fail:` without clearing it.

__ceph_remove_cap() consults that flag to decide whether cap releases
should be queued. A reconnect-preparation failure therefore leaves the
session in reconnect mode from the cap-release path's point of view
and can strand release work until some later state transition repairs
it.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-04-22 01:40:23 +02:00
Max Kellermann 803447f93d ceph: only d_add() negative dentries when they are unhashed
Ceph can call d_add(dentry, NULL) on a negative dentry that is already
present in the primary dcache hash.

In the current VFS that is not safe.  d_add() goes through __d_add()
to __d_rehash(), which unconditionally reinserts dentry->d_hash into
the hlist_bl bucket.  If the dentry is already hashed, reinserting the
same node can corrupt the bucket, including creating a self-loop.
Once that happens, __d_lookup() can spin forever in the hlist_bl walk,
typically looping only on the d_name.hash mismatch check and
eventually triggering RCU stall reports like this one:

 rcu: INFO: rcu_sched self-detected stall on CPU
 rcu:         87-....: (2100 ticks this GP) idle=3a4c/1/0x4000000000000000 softirq=25003319/25003319 fqs=829
 rcu:         (t=2101 jiffies g=79058445 q=698988 ncpus=192)
 CPU: 87 UID: 2952868916 PID: 3933303 Comm: php-cgi8.3 Not tainted 6.18.17-i1-amd #950 NONE
 Hardware name: Dell Inc. PowerEdge R7615/0G9DHV, BIOS 1.6.6 09/22/2023
 RIP: 0010:__d_lookup+0x46/0xb0
 Code: c1 e8 07 48 8d 04 c2 48 8b 00 49 89 fc 49 89 f5 48 89 c3 48 83 e3 fe 48 83 f8 01 77 0f eb 2d 0f 1f 44 00 00 48 8b 1b 48 85 db <74> 20 39 6b 18 75 f3 48 8d 7b 78 e8 ba 85 d0 00 4c 39 63 10 74 1f
 RSP: 0018:ff745a70c8253898 EFLAGS: 00000282
 RAX: ff26e470054cb208 RBX: ff26e470054cb208 RCX: 000000006e958966
 RDX: ff26e48267340000 RSI: ff745a70c82539b0 RDI: ff26e458f74655c0
 RBP: 000000006e958966 R08: 0000000000000180 R09: 9cd08d909b919a89
 R10: ff26e458f74655c0 R11: 0000000000000000 R12: ff26e458f74655c0
 R13: ff745a70c82539b0 R14: d0d0d0d0d0d0d0d0 R15: 2f2f2f2f2f2f2f2f
 FS:  00007f5770896980(0000) GS:ff26e482c5d88000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f5764de50c0 CR3: 000000a72abb5001 CR4: 0000000000771ef0
 PKRU: 55555554
 Call Trace:
  <TASK>
  lookup_fast+0x9f/0x100
  walk_component+0x1f/0x150
  link_path_walk+0x20e/0x3d0
  path_lookupat+0x68/0x180
  filename_lookup+0xdc/0x1e0
  vfs_statx+0x6c/0x140
  vfs_fstatat+0x67/0xa0
  __do_sys_newfstatat+0x24/0x60
  do_syscall_64+0x6a/0x230
  entry_SYSCALL_64_after_hwframe+0x76/0x7e

This is reachable with reused cached negative dentries.  A Ceph lookup
or atomic_open can be handed a negative dentry that is already hashed,
and fs/ceph/dir.c then hits one of two paths that incorrectly assume
"negative" also means "unhashed":

  - ceph_finish_lookup():
      MDS reply is -ENOENT with no trace
      -> d_add(dentry, NULL)

  - ceph_lookup():
      local ENOENT fast path for a complete directory with shared caps
      -> d_add(dentry, NULL)

Both paths can therefore re-add an already-hashed negative dentry.

Ceph already uses the correct pattern elsewhere: ceph_fill_trace() only
calls d_add(dn, NULL) for a negative null-dentry reply when d_unhashed(dn)
is true.

Fix both fs/ceph/dir.c sites the same way: only call d_add() for a
negative dentry when it is actually unhashed.  If the negative dentry
is already hashed, leave it in place and reuse it as-is.

This preserves the existing behavior for unhashed dentries while
avoiding d_hash list corruption for reused hashed negatives.

Cc: stable@vger.kernel.org
Fixes: 2817b000b0 ("ceph: directory operations")
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-04-22 01:40:23 +02:00
Sam Edwards a0d9555bf9 ceph: fix num_ops off-by-one when crypto allocation fails
move_dirty_folio_in_page_array() may fail if the file is encrypted, the
dirty folio is not the first in the batch, and it fails to allocate a
bounce buffer to hold the ciphertext. When that happens,
ceph_process_folio_batch() simply redirties the folio and flushes the
current batch -- it can retry that folio in a future batch.

However, if this failed folio is not contiguous with the last folio that
did make it into the batch, then ceph_process_folio_batch() has already
incremented `ceph_wbc->num_ops`; because it doesn't follow through and
add the discontiguous folio to the array, ceph_submit_write() -- which
expects that `ceph_wbc->num_ops` accurately reflects the number of
contiguous ranges (and therefore the required number of "write extent"
ops) in the writeback -- will panic the kernel:

    BUG_ON(ceph_wbc->op_idx + 1 != req->r_num_ops);

This issue can be reproduced on affected kernels by writing to
fscrypt-enabled CephFS file(s) with a 4KiB-written/4KiB-skipped/repeat
pattern (total filesize should not matter) and gradually increasing the
system's memory pressure until a bounce buffer allocation fails.

Fix this crash by decrementing `ceph_wbc->num_ops` back to the correct
value when move_dirty_folio_in_page_array() fails, but the folio already
started counting a new (i.e. still-empty) extent.

The defect corrected by this patch has existed since 2022 (see first
`Fixes:`), but another bug blocked multi-folio encrypted writeback until
recently (see second `Fixes:`). The second commit made it into 6.18.16,
6.19.6, and 7.0-rc1, unmasking the panic in those versions. This patch
therefore fixes a regression (panic) introduced by cac190c767.

Cc: stable@vger.kernel.org
Fixes: d55207717d ("ceph: add encryption support to writepage and writepages")
Fixes: cac190c767 ("ceph: fix write storm on fscrypted files")
Signed-off-by: Sam Edwards <CFSworks@gmail.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-04-22 01:40:22 +02:00
Linus Torvalds 292a2bcd17 Merge tag 'pull-dcache-busy-wait' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull dcache busy loop updates from Al Viro:
 "Fix livelocks in shrink_dcache_tree()

  If shrink_dcache_tree() finds a dentry in the middle of being killed
  by another thread, it has to wait until the victim finishes dying,
  gets detached from the tree and ceases to pin its parent.

  The way we used to deal with that amounted to busy-wait;
  unfortunately, it's not just inefficient but can lead to reliably
  reproducible hard livelocks.

  Solved by having shrink_dentry_tree() attach a completion to such
  dentry, with dentry_unlist() calling complete() on all objects
  attached to it. With a bit of care it can be done without growing
  struct dentry or adding overhead in normal case"

* tag 'pull-dcache-busy-wait' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  get rid of busy-waiting in shrink_dcache_tree()
  dcache.c: more idiomatic "positives are not allowed" sanity checks
  struct dentry: make ->d_u anonymous
  for_each_alias(): helper macro for iterating through dentries of given inode
2026-04-21 07:30:44 -07:00
Linus Torvalds 334fbe734e Merge tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:

 - "maple_tree: Replace big node with maple copy" (Liam Howlett)

   Mainly prepararatory work for ongoing development but it does reduce
   stack usage and is an improvement.

 - "mm, swap: swap table phase III: remove swap_map" (Kairui Song)

   Offers memory savings by removing the static swap_map. It also yields
   some CPU savings and implements several cleanups.

 - "mm: memfd_luo: preserve file seals" (Pratyush Yadav)

   File seal preservation to LUO's memfd code

 - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan
   Chen)

   Additional userspace stats reportng to zswap

 - "arch, mm: consolidate empty_zero_page" (Mike Rapoport)

   Some cleanups for our handling of ZERO_PAGE() and zero_pfn

 - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu
   Han)

   A robustness improvement and some cleanups in the kmemleak code

 - "Improve khugepaged scan logic" (Vernon Yang)

   Improve khugepaged scan logic and reduce CPU consumption by
   prioritizing scanning tasks that access memory frequently

 - "Make KHO Stateless" (Jason Miu)

   Simplify Kexec Handover by transitioning KHO from an xarray-based
   metadata tracking system with serialization to a radix tree data
   structure that can be passed directly to the next kernel

 - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas
   Ballasi and Steven Rostedt)

   Enhance vmscan's tracepointing

 - "mm: arch/shstk: Common shadow stack mapping helper and
   VM_NOHUGEPAGE" (Catalin Marinas)

   Cleanup for the shadow stack code: remove per-arch code in favour of
   a generic implementation

 - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin)

   Fix a WARN() which can be emitted the KHO restores a vmalloc area

 - "mm: Remove stray references to pagevec" (Tal Zussman)

   Several cleanups, mainly udpating references to "struct pagevec",
   which became folio_batch three years ago

 - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl
   Shutsemau)

   Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail
   pages encode their relationship to the head page

 - "mm/damon/core: improve DAMOS quota efficiency for core layer
   filters" (SeongJae Park)

   Improve two problematic behaviors of DAMOS that makes it less
   efficient when core layer filters are used

 - "mm/damon: strictly respect min_nr_regions" (SeongJae Park)

   Improve DAMON usability by extending the treatment of the
   min_nr_regions user-settable parameter

 - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka)

   The proper fix for a previously hotfixed SMP=n issue. Code
   simplifications and cleanups ensued

 - "mm: cleanups around unmapping / zapping" (David Hildenbrand)

   A bunch of cleanups around unmapping and zapping. Mostly
   simplifications, code movements, documentation and renaming of
   zapping functions

 - "support batched checking of the young flag for MGLRU" (Baolin Wang)

   Batched checking of the young flag for MGLRU. It's part cleanups; one
   benchmark shows large performance benefits for arm64

 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner)

   memcg cleanup and robustness improvements

 - "Allow order zero pages in page reporting" (Yuvraj Sakshith)

   Enhance free page reporting - it is presently and undesirably order-0
   pages when reporting free memory.

 - "mm: vma flag tweaks" (Lorenzo Stoakes)

   Cleanup work following from the recent conversion of the VMA flags to
   a bitmap

 - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae
   Park)

   Add some more developer-facing debug checks into DAMON core

 - "mm/damon: test and document power-of-2 min_region_sz requirement"
   (SeongJae Park)

   An additional DAMON kunit test and makes some adjustments to the
   addr_unit parameter handling

 - "mm/damon/core: make passed_sample_intervals comparisons
   overflow-safe" (SeongJae Park)

   Fix a hard-to-hit time overflow issue in DAMON core

 - "mm/damon: improve/fixup/update ratio calculation, test and
   documentation" (SeongJae Park)

   A batch of misc/minor improvements and fixups for DAMON

 - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David
   Hildenbrand)

   Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code
   movement was required.

 - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky)

   A somewhat random mix of fixups, recompression cleanups and
   improvements in the zram code

 - "mm/damon: support multiple goal-based quota tuning algorithms"
   (SeongJae Park)

   Extend DAMOS quotas goal auto-tuning to support multiple tuning
   algorithms that users can select

 - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao)

   Fix the khugpaged sysfs handling so we no longer spam the logs with
   reams of junk when starting/stopping khugepaged

 - "mm: improve map count checks" (Lorenzo Stoakes)

   Provide some cleanups and slight fixes in the mremap, mmap and vma
   code

 - "mm/damon: support addr_unit on default monitoring targets for
   modules" (SeongJae Park)

   Extend the use of DAMON core's addr_unit tunable

 - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache)

   Cleanups to khugepaged and is a base for Nico's planned khugepaged
   mTHP support

 - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand)

   Code movement and cleanups in the memhotplug and sparsemem code

 - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup
   CONFIG_MIGRATION" (David Hildenbrand)

   Rationalize some memhotplug Kconfig support

 - "change young flag check functions to return bool" (Baolin Wang)

   Cleanups to change all young flag check functions to return bool

 - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh
   Law and SeongJae Park)

   Fix a few potential DAMON bugs

 - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo
   Stoakes)

   Convert a lot of the existing use of the legacy vm_flags_t data type
   to the new vma_flags_t type which replaces it. Mainly in the vma
   code.

 - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes)

   Expand the mmap_prepare functionality, which is intended to replace
   the deprecated f_op->mmap hook which has been the source of bugs and
   security issues for some time. Cleanups, documentation, extension of
   mmap_prepare into filesystem drivers

 - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes)

   Simplify and clean up zap_huge_pmd(). Additional cleanups around
   vm_normal_folio_pmd() and the softleaf functionality are performed.

* tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
  mm: fix deferred split queue races during migration
  mm/khugepaged: fix issue with tracking lock
  mm/huge_memory: add and use has_deposited_pgtable()
  mm/huge_memory: add and use normal_or_softleaf_folio_pmd()
  mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio()
  mm/huge_memory: separate out the folio part of zap_huge_pmd()
  mm/huge_memory: use mm instead of tlb->mm
  mm/huge_memory: remove unnecessary sanity checks
  mm/huge_memory: deduplicate zap deposited table call
  mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE()
  mm/huge_memory: add a common exit path to zap_huge_pmd()
  mm/huge_memory: handle buggy PMD entry in zap_huge_pmd()
  mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc
  mm/huge: avoid big else branch in zap_huge_pmd()
  mm/huge_memory: simplify vma_is_specal_huge()
  mm: on remap assert that input range within the proposed VMA
  mm: add mmap_action_map_kernel_pages[_full]()
  uio: replace deprecated mmap hook with mmap_prepare in uio_info
  drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare
  mm: allow handling of stacked mmap_prepare hooks in more drivers
  ...
2026-04-15 12:59:16 -07:00
Linus Torvalds b7d74ea0fd Merge tag 'vfs-7.1-rc1.kino' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs i_ino updates from Christian Brauner:
 "For historical reasons, the inode->i_ino field is an unsigned long,
  which means that it's 32 bits on 32 bit architectures. This has caused
  a number of filesystems to implement hacks to hash a 64-bit identifier
  into a 32-bit field, and deprives us of a universal identifier field
  for an inode.

  This changes the inode->i_ino field from an unsigned long to a u64.
  This shouldn't make any material difference on 64-bit hosts, but
  32-bit hosts will see struct inode grow by at least 4 bytes. This
  could have effects on slabcache sizes and field alignment.

  The bulk of the changes are to format strings and tracepoints, since
  the kernel itself doesn't care that much about the i_ino field. The
  first patch changes some vfs function arguments, so check that one out
  carefully.

  With this change, we may be able to shrink some inode structures. For
  instance, struct nfs_inode has a fileid field that holds the 64-bit
  inode number. With this set of changes, that field could be
  eliminated. I'd rather leave that sort of cleanups for later just to
  keep this simple"

* tag 'vfs-7.1-rc1.kino' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  nilfs2: fix 64-bit division operations in nilfs_bmap_find_target_in_group()
  EVM: add comment describing why ino field is still unsigned long
  vfs: remove externs from fs.h on functions modified by i_ino widening
  treewide: fix missed i_ino format specifier conversions
  ext4: fix signed format specifier in ext4_load_inode trace event
  treewide: change inode->i_ino from unsigned long to u64
  nilfs2: widen trace event i_ino fields to u64
  f2fs: widen trace event i_ino fields to u64
  ext4: widen trace event i_ino fields to u64
  zonefs: widen trace event i_ino fields to u64
  hugetlbfs: widen trace event i_ino fields to u64
  ext2: widen trace event i_ino fields to u64
  cachefiles: widen trace event i_ino fields to u64
  vfs: widen trace event i_ino fields to u64
  net: change sock.sk_ino and sock_i_ino() to u64
  audit: widen ino fields to u64
  vfs: widen inode hash/lookup functions to u64
2026-04-13 12:19:01 -07:00
Tal Zussman 4e1d77a8f3 folio_batch: rename pagevec.h to folio_batch.h
struct pagevec was removed in commit 1e0877d58b ("mm: remove struct
pagevec").  Rename include/linux/pagevec.h to reflect reality and update
includes tree-wide.  Add the new filename to MAINTAINERS explicitly, as it
no longer matches the "include/linux/page[-_]*" pattern in MEMORY
MANAGEMENT - CORE.

Link: https://lkml.kernel.org/r/20260225-pagevec_cleanup-v2-3-716868cc2d11@columbia.edu
Signed-off-by: Tal Zussman <tz2294@columbia.edu>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05 13:53:07 -07:00
Al Viro 2420067cec struct dentry: make ->d_u anonymous
Making ->d_rcu and (then) ->d_child overlapping dates back to
2006; anon unions support had been added to gcc only in 4.6
(2011) and the minimal gcc version hadn't been bumped to that
until 4.19 (2018).

These days there's no reason not to keep that union named.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2026-04-02 03:47:31 -04:00
Al Viro 408d8af01f for_each_alias(): helper macro for iterating through dentries of given inode
Most of the places using d_alias are loops iterating through all aliases for
given inode; introduce a helper macro (for_each_alias(dentry, inode))
and convert open-coded instances of such loop to it.

They are easier to read that way and it reduces the noise on the next steps.

You _must_ hold inode->i_lock over that thing.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2026-04-02 03:45:02 -04:00
Hristo Venev 081a0b78ef ceph: do not skip the first folio of the next object in writeback
When `ceph_process_folio_batch` encounters a folio past the end of the
current object, it should leave it in the batch so that it is picked up
in the next iteration.

Removing the folio from the batch means that it does not get written
back and remains dirty instead. This makes `fsync()` silently skip some
of the data, delays capability release, and breaks coherence with
`O_DIRECT`.

The link below contains instructions for reproducing the bug.

Cc: stable@vger.kernel.org
Fixes: ce80b76dd3 ("ceph: introduce ceph_process_folio_batch() method")
Link: https://tracker.ceph.com/issues/75156
Signed-off-by: Hristo Venev <hristo@venev.name>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-03-09 12:34:40 +01:00
Max Kellermann 040d159a45 ceph: fix memory leaks in ceph_mdsc_build_path()
Add __putname() calls to error code paths that did not free the "path"
pointer obtained by __getname().  If ownership of this pointer is not
passed to the caller via path_info.path, the function must free it
before returning.

Cc: stable@vger.kernel.org
Fixes: 3fd945a79e ("ceph: encode encrypted name in ceph_mdsc_build_path and dentry release")
Fixes: 550f7ca98e ("ceph: give up on paths longer than PATH_MAX")
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-03-09 12:34:40 +01:00
Max Kellermann 43323a5934 ceph: add a bunch of missing ceph_path_info initializers
ceph_mdsc_build_path() must be called with a zero-initialized
ceph_path_info parameter, or else the following
ceph_mdsc_free_path_info() may crash.

Example crash (on Linux 6.18.12):

  virt_to_cache: Object is not a Slab page!
  WARNING: CPU: 184 PID: 2871736 at mm/slub.c:6732 kmem_cache_free+0x316/0x400
  [...]
  Call Trace:
   [...]
   ceph_open+0x13d/0x3e0
   do_dentry_open+0x134/0x480
   vfs_open+0x2a/0xe0
   path_openat+0x9a3/0x1160
  [...]
  cache_from_obj: Wrong slab cache. names_cache but object is from ceph_inode_info
  WARNING: CPU: 184 PID: 2871736 at mm/slub.c:6746 kmem_cache_free+0x2dd/0x400
  [...]
  kernel BUG at mm/slub.c:634!
  Oops: invalid opcode: 0000 [#1] SMP NOPTI
  RIP: 0010:__slab_free+0x1a4/0x350

Some of the ceph_mdsc_build_path() callers had initializers, but
others had not, even though they were all added by commit 15f519e9f8
("ceph: fix race condition validating r_parent before applying state").
The ones without initializer are suspectible to random crashes.  (I can
imagine it could even be possible to exploit this bug to elevate
privileges.)

Unfortunately, these Ceph functions are undocumented and its semantics
can only be derived from the code.  I see that ceph_mdsc_build_path()
initializes the structure only on success, but not on error.

Calling ceph_mdsc_free_path_info() after a failed
ceph_mdsc_build_path() call does not even make sense, but that's what
all callers do, and for it to be safe, the structure must be
zero-initialized.  The least intrusive approach to fix this is
therefore to add initializers everywhere.

Cc: stable@vger.kernel.org
Fixes: 15f519e9f8 ("ceph: fix race condition validating r_parent before applying state")
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-03-09 12:34:40 +01:00
Max Kellermann ce0123cbb4 ceph: fix i_nlink underrun during async unlink
During async unlink, we drop the `i_nlink` counter before we receive
the completion (that will eventually update the `i_nlink`) because "we
assume that the unlink will succeed".  That is not a bad idea, but it
races against deletions by other clients (or against the completion of
our own unlink) and can lead to an underrun which emits a WARNING like
this one:

 WARNING: CPU: 85 PID: 25093 at fs/inode.c:407 drop_nlink+0x50/0x68
 Modules linked in:
 CPU: 85 UID: 3221252029 PID: 25093 Comm: php-cgi8.1 Not tainted 6.14.11-cm4all1-ampere #655
 Hardware name: Supermicro ARS-110M-NR/R12SPD-A, BIOS 1.1b 10/17/2023
 pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : drop_nlink+0x50/0x68
 lr : ceph_unlink+0x6c4/0x720
 sp : ffff80012173bc90
 x29: ffff80012173bc90 x28: ffff086d0a45aaf8 x27: ffff0871d0eb5680
 x26: ffff087f2a64a718 x25: 0000020000000180 x24: 0000000061c88647
 x23: 0000000000000002 x22: ffff07ff9236d800 x21: 0000000000001203
 x20: ffff07ff9237b000 x19: ffff088b8296afc0 x18: 00000000f3c93365
 x17: 0000000000070000 x16: ffff08faffcbdfe8 x15: ffff08faffcbdfec
 x14: 0000000000000000 x13: 45445f65645f3037 x12: 34385f6369706f74
 x11: 0000a2653104bb20 x10: ffffd85f26d73290 x9 : ffffd85f25664f94
 x8 : 00000000000000c0 x7 : 0000000000000000 x6 : 0000000000000002
 x5 : 0000000000000081 x4 : 0000000000000481 x3 : 0000000000000000
 x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff08727d3f91e8
 Call trace:
  drop_nlink+0x50/0x68 (P)
  vfs_unlink+0xb0/0x2e8
  do_unlinkat+0x204/0x288
  __arm64_sys_unlinkat+0x3c/0x80
  invoke_syscall.constprop.0+0x54/0xe8
  do_el0_svc+0xa4/0xc8
  el0_svc+0x18/0x58
  el0t_64_sync_handler+0x104/0x130
  el0t_64_sync+0x154/0x158

In ceph_unlink(), a call to ceph_mdsc_submit_request() submits the
CEPH_MDS_OP_UNLINK to the MDS, but does not wait for completion.

Meanwhile, between this call and the following drop_nlink() call, a
worker thread may process a CEPH_CAP_OP_IMPORT, CEPH_CAP_OP_GRANT or
just a CEPH_MSG_CLIENT_REPLY (the latter of which could be our own
completion).  These will lead to a set_nlink() call, updating the
`i_nlink` counter to the value received from the MDS.  If that new
`i_nlink` value happens to be zero, it is illegal to decrement it
further.  But that is exactly what ceph_unlink() will do then.

The WARNING can be reproduced this way:

1. Force async unlink; only the async code path is affected.  Having
   no real clue about Ceph internals, I was unable to find out why the
   MDS wouldn't give me the "Fxr" capabilities, so I patched
   get_caps_for_async_unlink() to always succeed.

   (Note that the WARNING dump above was found on an unpatched kernel,
   without this kludge - this is not a theoretical bug.)

2. Add a sleep call after ceph_mdsc_submit_request() so the unlink
   completion gets handled by a worker thread before drop_nlink() is
   called.  This guarantees that the `i_nlink` is already zero before
   drop_nlink() runs.

The solution is to skip the counter decrement when it is already zero,
but doing so without a lock is still racy (TOCTOU).  Since
ceph_fill_inode() and handle_cap_grant() both hold the
`ceph_inode_info.i_ceph_lock` spinlock while set_nlink() runs, this
seems like the proper lock to protect the `i_nlink` updates.

I found prior art in NFS and SMB (using `inode.i_lock`) and AFS (using
`afs_vnode.cb_lock`).  All three have the zero check as well.

Cc: stable@vger.kernel.org
Fixes: 2ccb45462a ("ceph: perform asynchronous unlink if we have sufficient caps")
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-03-09 12:34:40 +01:00
Jeff Layton 0b2600f81c treewide: change inode->i_ino from unsigned long to u64
On 32-bit architectures, unsigned long is only 32 bits wide, which
causes 64-bit inode numbers to be silently truncated. Several
filesystems (NFS, XFS, BTRFS, etc.) can generate inode numbers that
exceed 32 bits, and this truncation can lead to inode number collisions
and other subtle bugs on 32-bit systems.

Change the type of inode->i_ino from unsigned long to u64 to ensure that
inode numbers are always represented as 64-bit values regardless of
architecture. Update all format specifiers treewide from %lu/%lx to
%llu/%llx to match the new type, along with corresponding local variable
types.

This is the bulk treewide conversion. Earlier patches in this series
handled trace events separately to allow trace field reordering for
better struct packing on 32-bit.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20260304-iino-u64-v3-12-2257ad83d372@kernel.org
Acked-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-06 14:31:28 +01:00
Kees Cook 189f164e57 Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses
Conversion performed via this Coccinelle script:

  // SPDX-License-Identifier: GPL-2.0-only
  // Options: --include-headers-for-types --all-includes --include-headers --keep-comments
  virtual patch

  @gfp depends on patch && !(file in "tools") && !(file in "samples")@
  identifier ALLOC = {kmalloc_obj,kmalloc_objs,kmalloc_flex,
 		    kzalloc_obj,kzalloc_objs,kzalloc_flex,
		    kvmalloc_obj,kvmalloc_objs,kvmalloc_flex,
		    kvzalloc_obj,kvzalloc_objs,kvzalloc_flex};
  @@

  	ALLOC(...
  -		, GFP_KERNEL
  	)

  $ make coccicheck MODE=patch COCCI=gfp.cocci

Build and boot tested x86_64 with Fedora 42's GCC and Clang:

Linux version 6.19.0+ (user@host) (gcc (GCC) 15.2.1 20260123 (Red Hat 15.2.1-7), GNU ld version 2.44-12.fc42) #1 SMP PREEMPT_DYNAMIC 1970-01-01
Linux version 6.19.0+ (user@host) (clang version 20.1.8 (Fedora 20.1.8-4.fc42), LLD 20.1.8) #1 SMP PREEMPT_DYNAMIC 1970-01-01

Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-22 08:26:33 -08:00
Linus Torvalds bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook 69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00