211 Commits
Author SHA1 Message Date
Linus Torvalds ef3da345cc Merge tag 'vfs-7.1-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner:
 "Features:
   - coredump: add tracepoint for coredump events
   - fs: hide file and bfile caches behind runtime const machinery

  Fixes:
   - fix architecture-specific compat_ftruncate64 implementations
   - dcache: Limit the minimal number of bucket to two
   - fs/omfs: reject s_sys_blocksize smaller than OMFS_DIR_START
   - fs/mbcache: cancel shrink work before destroying the cache
   - dcache: permit dynamic_dname()s up to NAME_MAX

  Cleanups:
   - remove or unexport unused fs_context infrastructure
   - trivial ->setattr cleanups
   - selftests/filesystems: Assume that TIOCGPTPEER is defined
   - writeback: fix kernel-doc function name mismatch for wb_put_many()
   - autofs: replace manual symlink buffer allocation in autofs_dir_symlink
   - init/initramfs.c: trivial fix: FSM -> Finite-state machine
   - fs: remove stale and duplicate forward declarations
   - readdir: Introduce dirent_size()
   - fs: Replace user_access_{begin/end} by scoped user access
   - kernel: acct: fix duplicate word in comment
   - fs: write a better comment in step_into() concerning .mnt assignment
   - fs: attr: fix comment formatting and spelling issues"

* tag 'vfs-7.1-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (28 commits)
  dcache: permit dynamic_dname()s up to NAME_MAX
  fs: attr: fix comment formatting and spelling issues
  fs: hide file and bfile caches behind runtime const machinery
  fs: write a better comment in step_into() concerning .mnt assignment
  proc: rename proc_notify_change to proc_setattr
  proc: rename proc_setattr to proc_nochmod_setattr
  affs: rename affs_notify_change to affs_setattr
  adfs: rename adfs_notify_change to adfs_setattr
  hfs: update comments on hfs_inode_setattr
  kernel: acct: fix duplicate word in comment
  fs: Replace user_access_{begin/end} by scoped user access
  readdir: Introduce dirent_size()
  coredump: add tracepoint for coredump events
  fs: remove do_sys_truncate
  fs: pass on FTRUNCATE_* flags to do_truncate
  fs: fix archiecture-specific compat_ftruncate64
  fs: remove stale and duplicate forward declarations
  init/initramfs.c: trivial fix: FSM -> Finite-state machine
  autofs: replace manual symlink buffer allocation in autofs_dir_symlink
  fs/mbcache: cancel shrink work before destroying the cache
  ...
2026-04-13 14:20:11 -07:00
Breno LeitaoandChristian Brauner f30186b0c7 coredump: add tracepoint for coredump events
Coredump is a generally useful and interesting event in the lifetime
of a process. Add a tracepoint so it can be monitored through the
standard kernel tracing infrastructure.

BPF-based crash monitoring is an advanced approach that
allows real-time crash interception: by attaching a BPF program at
this point, tools can use bpf_get_stack() with BPF_F_USER_STACK to
capture the user-space stack trace at the exact moment of the crash,
before the process is fully terminated, without waiting for a
coredump file to be written and parsed.

However, there is currently no stable kernel API for this use case.
Existing tools rely on attaching fentry probes to do_coredump(),
which is an internal function whose signature changes across kernel
versions, breaking these tools.

Add a stable tracepoint that fires at the beginning of
do_coredump(), providing BPF programs a reliable attachment point.
At tracepoint time, the crashing process context is still live, so
BPF programs can call bpf_get_stack() with BPF_F_USER_STACK to
extract the user-space backtrace.

The tracepoint records:
  - sig: signal number that triggered the coredump
  - comm: process name

Example output:

  $ echo 1 > /sys/kernel/tracing/events/coredump/coredump/enable
  $ sleep 999 &
  $ kill -SEGV $!
  $ cat /sys/kernel/tracing/trace
  #           TASK-PID     CPU#  |||||  TIMESTAMP  FUNCTION
  #              | |         |   |||||     |         |
             sleep-634     [036] .....   145.222206: coredump: sig=11 comm=sleep

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260323-coredump_tracepoint-v2-1-afced083b38d@debian.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-23 13:15:52 +01:00
Linus Torvalds 32a92f8c89 Convert more 'alloc_obj' cases to default GFP_KERNEL arguments
This converts some of the visually simpler cases that have been split
over multiple lines.  I only did the ones that are easy to verify the
resulting diff by having just that final GFP_KERNEL argument on the next
line.

Somebody should probably do a proper coccinelle script for this, but for
me the trivial script actually resulted in an assertion failure in the
middle of the script.  I probably had made it a bit _too_ trivial.

So after fighting that far a while I decided to just do some of the
syntactically simpler cases with variations of the previous 'sed'
scripts.

The more syntactically complex multi-line cases would mostly really want
whitespace cleanup anyway.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 20:03:00 -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
Linus Torvalds 85f24b0ace Merge tag 'hardening-v7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull hardening updates from Kees Cook:
 "Mostly small cleanups and various scattered annotations and flex array
  warning fixes that we reviewed by unlanded in other trees. Introduces
  new annotation for expanding counted_by to pointer members, now that
  compiler behavior between GCC and Clang has been normalized.

   - Various missed __counted_by annotations (Thorsten Blum)

   - Various missed -Wflex-array-member-not-at-end fixes (Gustavo A. R.
     Silva)

   - Avoid leftover tempfiles for interrupted compile-time FORTIFY tests
     (Nicolas Schier)

   - Remove non-existant CONFIG_UBSAN_REPORT_FULL from docs (Stefan
     Wiehler)

   - fortify: Use C arithmetic not FIELD_xxx() in FORTIFY_REASON defines
     (David Laight)

   - Add __counted_by_ptr attribute, tests, and first user (Bill
     Wendling, Kees Cook)

   - Update MAINTAINERS file to make hardening section not include
     pstore"

* tag 'hardening-v7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  MAINTAINERS: pstore: Remove L: entry
  nfp: tls: Avoid -Wflex-array-member-not-at-end warnings
  carl9170: Avoid -Wflex-array-member-not-at-end warning
  coredump: Use __counted_by_ptr for struct core_name::corename
  lkdtm/bugs: Add __counted_by_ptr() test PTR_BOUNDS
  compiler_types.h: Attributes: Add __counted_by_ptr macro
  fortify: Cleanup temp file also on non-successful exit
  fortify: Rename temporary file to match ignore pattern
  fortify: Use C arithmetic not FIELD_xxx() in FORTIFY_REASON defines
  ecryptfs: Annotate struct ecryptfs_message with __counted_by
  fs/xattr: Annotate struct simple_xattr with __counted_by
  crypto: af_alg - Annotate struct af_alg_iv with __counted_by
  Kconfig.ubsan: Remove CONFIG_UBSAN_REPORT_FULL from documentation
  drm/nouveau: fifo: Avoid -Wflex-array-member-not-at-end warning
2026-02-10 08:54:13 -08:00
Kees Cook fac4ab5cd0 coredump: Use __counted_by_ptr for struct core_name::corename
Use the __counted_by annotation now available for struct pointer
members, __counted_by_ptr(). Move assignments to immediately
after allocation.

Link: https://patch.msgid.link/20251020220118.1226740-3-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
2026-01-17 11:00:37 -08:00
Al Viro e50aae1d39 non-consuming variants of do_{unlinkat,rmdir}()
similar to previous commit; replacements are filename_{unlinkat,rmdir}()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2026-01-16 12:51:50 -05:00
Linus Torvalds 8f7aa3d3c7 Merge tag 'net-next-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski:
 "Core & protocols:

   - Replace busylock at the Tx queuing layer with a lockless list.

     Resulting in a 300% (4x) improvement on heavy TX workloads, sending
     twice the number of packets per second, for half the cpu cycles.

   - Allow constantly busy flows to migrate to a more suitable CPU/NIC
     queue.

     Normally we perform queue re-selection when flow comes out of idle,
     but under extreme circumstances the flows may be constantly busy.

     Add sysctl to allow periodic rehashing even if it'd risk packet
     reordering.

   - Optimize the NAPI skb cache, make it larger, use it in more paths.

   - Attempt returning Tx skbs to the originating CPU (like we already
     did for Rx skbs).

   - Various data structure layout and prefetch optimizations from Eric.

   - Remove ktime_get() from the recvmsg() fast path, ktime_get() is
     sadly quite expensive on recent AMD machines.

   - Extend threaded NAPI polling to allow the kthread busy poll for
     packets.

   - Make MPTCP use Rx backlog processing. This lowers the lock
     pressure, improving the Rx performance.

   - Support memcg accounting of MPTCP socket memory.

   - Allow admin to opt sockets out of global protocol memory accounting
     (using a sysctl or BPF-based policy). The global limits are a poor
     fit for modern container workloads, where limits are imposed using
     cgroups.

   - Improve heuristics for when to kick off AF_UNIX garbage collection.

   - Allow users to control TCP SACK compression, and default to 33% of
     RTT.

   - Add tcp_rcvbuf_low_rtt sysctl to let datacenter users avoid
     unnecessarily aggressive rcvbuf growth and overshot when the
     connection RTT is low.

   - Preserve skb metadata space across skb_push / skb_pull operations.

   - Support for IPIP encapsulation in the nftables flowtable offload.

   - Support appending IP interface information to ICMP messages (RFC
     5837).

   - Support setting max record size in TLS (RFC 8449).

   - Remove taking rtnl_lock from RTM_GETNEIGHTBL and RTM_SETNEIGHTBL.

   - Use a dedicated lock (and RCU) in MPLS, instead of rtnl_lock.

   - Let users configure the number of write buffers in SMC.

   - Add new struct sockaddr_unsized for sockaddr of unknown length,
     from Kees.

   - Some conversions away from the crypto_ahash API, from Eric Biggers.

   - Some preparations for slimming down struct page.

   - YAML Netlink protocol spec for WireGuard.

   - Add a tool on top of YAML Netlink specs/lib for reporting commonly
     computed derived statistics and summarized system state.

  Driver API:

   - Add CAN XL support to the CAN Netlink interface.

   - Add uAPI for reporting PHY Mean Square Error (MSE) diagnostics, as
     defined by the OPEN Alliance's "Advanced diagnostic features for
     100BASE-T1 automotive Ethernet PHYs" specification.

   - Add DPLL phase-adjust-gran pin attribute (and implement it in
     zl3073x).

   - Refactor xfrm_input lock to reduce contention when NIC offloads
     IPsec and performs RSS.

   - Add info to devlink params whether the current setting is the
     default or a user override. Allow resetting back to default.

   - Add standard device stats for PSP crypto offload.

   - Leverage DSA frame broadcast to implement simple HSR frame
     duplication for a lot of switches without dedicated HSR offload.

   - Add uAPI defines for 1.6Tbps link modes.

  Device drivers:

   - Add Motorcomm YT921x gigabit Ethernet switch support.

   - Add MUCSE driver for N500/N210 1GbE NIC series.

   - Convert drivers to support dedicated ops for timestamping control,
     and away from the direct IOCTL handling. While at it support GET
     operations for PHY timestamping.

   - Add (and convert most drivers to) a dedicated ethtool callback for
     reading the Rx ring count.

   - Significant refactoring efforts in the STMMAC driver, which
     supports Synopsys turn-key MAC IP integrated into a ton of SoCs.

   - Ethernet high-speed NICs:
      - Broadcom (bnxt):
         - support PPS in/out on all pins
      - Intel (100G, ice, idpf):
         - ice: implement standard ethtool and timestamping stats
         - i40e: support setting the max number of MAC addresses per VF
         - iavf: support RSS of GTP tunnels for 5G and LTE deployments
      - nVidia/Mellanox (mlx5):
         - reduce downtime on interface reconfiguration
         - disable being an XDP redirect target by default (same as
           other drivers) to avoid wasting resources if feature is
           unused
      - Meta (fbnic):
         - add support for Linux-managed PCS on 25G, 50G, and 100G links
      - Wangxun:
         - support Rx descriptor merge, and Tx head writeback
         - support Rx coalescing offload
         - support 25G SPF and 40G QSFP modules

   - Ethernet virtual:
      - Google (gve):
         - allow ethtool to configure rx_buf_len
         - implement XDP HW RX Timestamping support for DQ descriptor
           format
      - Microsoft vNIC (mana):
         - support HW link state events
         - handle hardware recovery events when probing the device

   - Ethernet NICs consumer, and embedded:
      - usbnet: add support for Byte Queue Limits (BQL)
      - AMD (amd-xgbe):
         - add device selftests
      - NXP (enetc):
         - add i.MX94 support
      - Broadcom integrated MACs (bcmgenet, bcmasp):
         - bcmasp: add support for PHY-based Wake-on-LAN
      - Broadcom switches (b53):
         - support port isolation
         - support BCM5389/97/98 and BCM63XX ARL formats
      - Lantiq/MaxLinear switches:
         - support bridge FDB entries on the CPU port
         - use regmap for register access
         - allow user to enable/disable learning
         - support Energy Efficient Ethernet
         - support configuring RMII clock delays
         - add tagging driver for MaxLinear GSW1xx switches
      - Synopsys (stmmac):
         - support using the HW clock in free running mode
         - add Eswin EIC7700 support
         - add Rockchip RK3506 support
         - add Altera Agilex5 support
      - Cadence (macb):
         - cleanup and consolidate descriptor and DMA address handling
         - add EyeQ5 support
      - TI:
         - icssg-prueth: support AF_XDP
      - Airoha access points:
         - add missing Ethernet stats and link state callback
         - add AN7583 support
         - support out-of-order Tx completion processing
      - Power over Ethernet:
         - pd692x0: preserve PSE configuration across reboots
         - add support for TPS23881B devices

   - Ethernet PHYs:
      - Open Alliance OATC14 10BASE-T1S PHY cable diagnostic support
      - Support 50G SerDes and 100G interfaces in Linux-managed PHYs
      - micrel:
         - support for non PTP SKUs of lan8814
         - enable in-band auto-negotiation on lan8814
      - realtek:
         - cable testing support on RTL8224
         - interrupt support on RTL8221B
      - motorcomm: support for PHY LEDs on YT853
      - microchip: support for LAN867X Rev.D0 PHYs w/ SQI and cable diag
      - mscc: support for PHY LED control

   - CAN drivers:
      - m_can: add support for optional reset and system wake up
      - remove can_change_mtu() obsoleted by core handling
      - mcp251xfd: support GPIO controller functionality

   - Bluetooth:
      - add initial support for PASTa

   - WiFi:
      - split ieee80211.h file, it's way too big
      - improvements in VHT radiotap reporting, S1G, Channel Switch
        Announcement handling, rate tracking in mesh networks
      - improve multi-radio monitor mode support, and add a cfg80211
        debugfs interface for it
      - HT action frame handling on 6 GHz
      - initial chanctx work towards NAN
      - MU-MIMO sniffer improvements

   - WiFi drivers:
      - RealTek (rtw89):
         - support USB devices RTL8852AU and RTL8852CU
         - initial work for RTL8922DE
         - improved injection support
      - Intel:
         - iwlwifi: new sniffer API support
      - MediaTek (mt76):
         - WED support for >32-bit DMA
         - airoha NPU support
         - regdomain improvements
         - continued WiFi7/MLO work
      - Qualcomm/Atheros:
         - ath10k: factory test support
         - ath11k: TX power insertion support
         - ath12k: BSS color change support
         - ath12k: statistics improvements
      - brcmfmac: Acer A1 840 tablet quirk
      - rtl8xxxu: 40 MHz connection fixes/support"

* tag 'net-next-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1381 commits)
  net: page_pool: sanitise allocation order
  net: page pool: xa init with destroy on pp init
  net/mlx5e: Support XDP target xmit with dummy program
  net/mlx5e: Update XDP features in switch channels
  selftests/tc-testing: Test CAKE scheduler when enqueue drops packets
  net/sched: sch_cake: Fix incorrect qlen reduction in cake_drop
  wireguard: netlink: generate netlink code
  wireguard: uapi: generate header with ynl-gen
  wireguard: uapi: move flag enums
  wireguard: uapi: move enum wg_cmd
  wireguard: netlink: add YNL specification
  selftests: drv-net: Fix tolerance calculation in devlink_rate_tc_bw.py
  selftests: drv-net: Fix and clarify TC bandwidth split in devlink_rate_tc_bw.py
  selftests: drv-net: Set shell=True for sysfs writes in devlink_rate_tc_bw.py
  selftests: drv-net: Use Iperf3Runner in devlink_rate_tc_bw.py
  selftests: drv-net: introduce Iperf3Runner for measurement use cases
  selftests: drv-net: Add devlink_rate_tc_bw.py to TEST_PROGS
  net: ps3_gelic_net: Use napi_alloc_skb() and napi_gro_receive()
  Documentation: net: dsa: mention simple HSR offload helpers
  Documentation: net: dsa: mention availability of RedBox
  ...
2025-12-03 17:24:33 -08:00
Christian Brauner 545985dd37 coredump: use override credential guard
Use override credential guards for scoped credential override with
automatic restoration on scope exit.

Link: https://patch.msgid.link/20251103-work-creds-guards-prepare_creds-v1-10-b447b82f2c9b@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-05 23:11:52 +01:00
Christian Brauner 8ed3473c5a coredump: use prepare credential guard
Use the prepare credential guard for allocating a new set of
credentials.

Link: https://patch.msgid.link/20251103-work-creds-guards-prepare_creds-v1-9-b447b82f2c9b@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-05 23:11:52 +01:00
Christian Brauner af9803d4b8 coredump: split out do_coredump() from vfs_coredump()
Make the function easier to follow and prepare for some of the following
changes.

Link: https://patch.msgid.link/20251103-work-creds-guards-prepare_creds-v1-8-b447b82f2c9b@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-05 23:11:52 +01:00
Christian Brauner 313a335057 coredump: mark struct mm_struct as const
We don't actually modify it.

Link: https://patch.msgid.link/20251103-work-creds-guards-prepare_creds-v1-7-b447b82f2c9b@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-05 23:11:51 +01:00
Christian Brauner 1ec760fb42 coredump: pass struct linux_binfmt as const
We don't actually modify it.

Link: https://patch.msgid.link/20251103-work-creds-guards-prepare_creds-v1-6-b447b82f2c9b@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-05 23:11:51 +01:00
Christian Brauner eb937201ba coredump: move revert_cred() before coredump_cleanup()
There's no need to pin the credentials across the coredump_cleanup()
call. Nothing in there depends on elevated credentials.

Link: https://patch.msgid.link/20251103-work-creds-guards-prepare_creds-v1-5-b447b82f2c9b@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-05 23:11:51 +01:00
Kees CookandJakub Kicinski 85cb0757d7 net: Convert proto_ops connect() callbacks to use sockaddr_unsized
Update all struct proto_ops connect() callback function prototypes from
"struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the
compiler about object sizes. Calls into struct proto handlers gain casts
that will be removed in the struct proto conversion patch.

No binary changes expected.

Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-3-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-11-04 19:10:32 -08:00
Christian Brauner a779e27f24 coredump: fix core_pattern input validation
In be1e028302 ("coredump: don't pointlessly check and spew warnings")
we tried to fix input validation so it only happens during a write to
core_pattern. This would avoid needlessly logging a lot of warnings
during a read operation. However the logic accidently got inverted in
this commit. Fix it so the input validation only happens on write and is
skipped on read.

Fixes: be1e028302 ("coredump: don't pointlessly check and spew warnings")
Fixes: 16195d2c7d ("coredump: validate socket name as it is written")
Reviewed-by: Jan Kara <jack@suse.cz>
Reported-by: Yu Watanabe <watanabe.yu@gmail.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-10-07 13:12:46 +02:00
Linus Torvalds 8804d970fa Merge tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:

 - "mm, swap: improve cluster scan strategy" from Kairui Song improves
   performance and reduces the failure rate of swap cluster allocation

 - "support large align and nid in Rust allocators" from Vitaly Wool
   permits Rust allocators to set NUMA node and large alignment when
   perforning slub and vmalloc reallocs

 - "mm/damon/vaddr: support stat-purpose DAMOS" from Yueyang Pan extend
   DAMOS_STAT's handling of the DAMON operations sets for virtual
   address spaces for ops-level DAMOS filters

 - "execute PROCMAP_QUERY ioctl under per-vma lock" from Suren
   Baghdasaryan reduces mmap_lock contention during reads of
   /proc/pid/maps

 - "mm/mincore: minor clean up for swap cache checking" from Kairui Song
   performs some cleanup in the swap code

 - "mm: vm_normal_page*() improvements" from David Hildenbrand provides
   code cleanup in the pagemap code

 - "add persistent huge zero folio support" from Pankaj Raghav provides
   a block layer speedup by optionalls making the
   huge_zero_pagepersistent, instead of releasing it when its refcount
   falls to zero

 - "kho: fixes and cleanups" from Mike Rapoport adds a few touchups to
   the recently added Kexec Handover feature

 - "mm: make mm->flags a bitmap and 64-bit on all arches" from Lorenzo
   Stoakes turns mm_struct.flags into a bitmap. To end the constant
   struggle with space shortage on 32-bit conflicting with 64-bit's
   needs

 - "mm/swapfile.c and swap.h cleanup" from Chris Li cleans up some swap
   code

 - "selftests/mm: Fix false positives and skip unsupported tests" from
   Donet Tom fixes a few things in our selftests code

 - "prctl: extend PR_SET_THP_DISABLE to only provide THPs when advised"
   from David Hildenbrand "allows individual processes to opt-out of
   THP=always into THP=madvise, without affecting other workloads on the
   system".

   It's a long story - the [1/N] changelog spells out the considerations

 - "Add and use memdesc_flags_t" from Matthew Wilcox gets us started on
   the memdesc project. Please see

      https://kernelnewbies.org/MatthewWilcox/Memdescs and
      https://blogs.oracle.com/linux/post/introducing-memdesc

 - "Tiny optimization for large read operations" from Chi Zhiling
   improves the efficiency of the pagecache read path

 - "Better split_huge_page_test result check" from Zi Yan improves our
   folio splitting selftest code

 - "test that rmap behaves as expected" from Wei Yang adds some rmap
   selftests

 - "remove write_cache_pages()" from Christoph Hellwig removes that
   function and converts its two remaining callers

 - "selftests/mm: uffd-stress fixes" from Dev Jain fixes some UFFD
   selftests issues

 - "introduce kernel file mapped folios" from Boris Burkov introduces
   the concept of "kernel file pages". Using these permits btrfs to
   account its metadata pages to the root cgroup, rather than to the
   cgroups of random inappropriate tasks

 - "mm/pageblock: improve readability of some pageblock handling" from
   Wei Yang provides some readability improvements to the page allocator
   code

 - "mm/damon: support ARM32 with LPAE" from SeongJae Park teaches DAMON
   to understand arm32 highmem

 - "tools: testing: Use existing atomic.h for vma/maple tests" from
   Brendan Jackman performs some code cleanups and deduplication under
   tools/testing/

 - "maple_tree: Fix testing for 32bit compiles" from Liam Howlett fixes
   a couple of 32-bit issues in tools/testing/radix-tree.c

 - "kasan: unify kasan_enabled() and remove arch-specific
   implementations" from Sabyrzhan Tasbolatov moves KASAN arch-specific
   initialization code into a common arch-neutral implementation

 - "mm: remove zpool" from Johannes Weiner removes zspool - an
   indirection layer which now only redirects to a single thing
   (zsmalloc)

 - "mm: task_stack: Stack handling cleanups" from Pasha Tatashin makes a
   couple of cleanups in the fork code

 - "mm: remove nth_page()" from David Hildenbrand makes rather a lot of
   adjustments at various nth_page() callsites, eventually permitting
   the removal of that undesirable helper function

 - "introduce kasan.write_only option in hw-tags" from Yeoreum Yun
   creates a KASAN read-only mode for ARM, using that architecture's
   memory tagging feature. It is felt that a read-only mode KASAN is
   suitable for use in production systems rather than debug-only

 - "mm: hugetlb: cleanup hugetlb folio allocation" from Kefeng Wang does
   some tidying in the hugetlb folio allocation code

 - "mm: establish const-correctness for pointer parameters" from Max
   Kellermann makes quite a number of the MM API functions more accurate
   about the constness of their arguments. This was getting in the way
   of subsystems (in this case CEPH) when they attempt to improving
   their own const/non-const accuracy

 - "Cleanup free_pages() misuse" from Vishal Moola fixes a number of
   code sites which were confused over when to use free_pages() vs
   __free_pages()

 - "Add Rust abstraction for Maple Trees" from Alice Ryhl makes the
   mapletree code accessible to Rust. Required by nouveau and by its
   forthcoming successor: the new Rust Nova driver

 - "selftests/mm: split_huge_page_test: split_pte_mapped_thp
   improvements" from David Hildenbrand adds a fix and some cleanups to
   the thp selftesting code

 - "mm, swap: introduce swap table as swap cache (phase I)" from Chris
   Li and Kairui Song is the first step along the path to implementing
   "swap tables" - a new approach to swap allocation and state tracking
   which is expected to yield speed and space improvements. This
   patchset itself yields a 5-20% performance benefit in some situations

 - "Some ptdesc cleanups" from Matthew Wilcox utilizes the new memdesc
   layer to clean up the ptdesc code a little

 - "Fix va_high_addr_switch.sh test failure" from Chunyu Hu fixes some
   issues in our 5-level pagetable selftesting code

 - "Minor fixes for memory allocation profiling" from Suren Baghdasaryan
   addresses a couple of minor issues in relatively new memory
   allocation profiling feature

 - "Small cleanups" from Matthew Wilcox has a few cleanups in
   preparation for more memdesc work

 - "mm/damon: add addr_unit for DAMON_LRU_SORT and DAMON_RECLAIM" from
   Quanmin Yan makes some changes to DAMON in furtherance of supporting
   arm highmem

 - "selftests/mm: Add -Wunreachable-code and fix warnings" from Muhammad
   Anjum adds that compiler check to selftests code and fixes the
   fallout, by removing dead code

 - "Improvements to Victim Process Thawing and OOM Reaper Traversal
   Order" from zhongjinji makes a number of improvements in the OOM
   killer: mainly thawing a more appropriate group of victim threads so
   they can release resources

 - "mm/damon: misc fixups and improvements for 6.18" from SeongJae Park
   is a bunch of small and unrelated fixups for DAMON

 - "mm/damon: define and use DAMON initialization check function" from
   SeongJae Park implement reliability and maintainability improvements
   to a recently-added bug fix

 - "mm/damon/stat: expose auto-tuned intervals and non-idle ages" from
   SeongJae Park provides additional transparency to userspace clients
   of the DAMON_STAT information

 - "Expand scope of khugepaged anonymous collapse" from Dev Jain removes
   some constraints on khubepaged's collapsing of anon VMAs. It also
   increases the success rate of MADV_COLLAPSE against an anon vma

 - "mm: do not assume file == vma->vm_file in compat_vma_mmap_prepare()"
   from Lorenzo Stoakes moves us further towards removal of
   file_operations.mmap(). This patchset concentrates upon clearing up
   the treatment of stacked filesystems

 - "mm: Improve mlock tracking for large folios" from Kiryl Shutsemau
   provides some fixes and improvements to mlock's tracking of large
   folios. /proc/meminfo's "Mlocked" field became more accurate

 - "mm/ksm: Fix incorrect accounting of KSM counters during fork" from
   Donet Tom fixes several user-visible KSM stats inaccuracies across
   forks and adds selftest code to verify these counters

 - "mm_slot: fix the usage of mm_slot_entry" from Wei Yang addresses
   some potential but presently benign issues in KSM's mm_slot handling

* tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (372 commits)
  mm: swap: check for stable address space before operating on the VMA
  mm: convert folio_page() back to a macro
  mm/khugepaged: use start_addr/addr for improved readability
  hugetlbfs: skip VMAs without shareable locks in hugetlb_vmdelete_list
  alloc_tag: fix boot failure due to NULL pointer dereference
  mm: silence data-race in update_hiwater_rss
  mm/memory-failure: don't select MEMORY_ISOLATION
  mm/khugepaged: remove definition of struct khugepaged_mm_slot
  mm/ksm: get mm_slot by mm_slot_entry() when slot is !NULL
  hugetlb: increase number of reserving hugepages via cmdline
  selftests/mm: add fork inheritance test for ksm_merging_pages counter
  mm/ksm: fix incorrect KSM counter handling in mm_struct during fork
  drivers/base/node: fix double free in register_one_node()
  mm: remove PMD alignment constraint in execmem_vmalloc()
  mm/memory_hotplug: fix typo 'esecially' -> 'especially'
  mm/rmap: improve mlock tracking for large folios
  mm/filemap: map entire large folio faultaround
  mm/fault: try to map the entire file folio in finish_fault()
  mm/rmap: mlock large folios in try_to_unmap_one()
  mm/rmap: fix a mlock race condition in folio_referenced_one()
  ...
2025-10-02 18:18:33 -07:00
Linus Torvalds b786405685 Merge tag 'vfs-6.18-rc1.workqueue' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs workqueue updates from Christian Brauner:
 "This contains various workqueue changes affecting the filesystem
  layer.

  Currently if a user enqueue a work item using schedule_delayed_work()
  the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use
  WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies
  to schedule_work() that is using system_wq and queue_work(), that
  makes use again of WORK_CPU_UNBOUND.

  This replaces the use of system_wq and system_unbound_wq. system_wq is
  a per-CPU workqueue which isn't very obvious from the name and
  system_unbound_wq is to be used when locality is not required.

  So this renames system_wq to system_percpu_wq, and system_unbound_wq
  to system_dfl_wq.

  This also adds a new WQ_PERCPU flag to allow the fs subsystem users to
  explicitly request the use of per-CPU behavior. Both WQ_UNBOUND and
  WQ_PERCPU flags coexist for one release cycle to allow callers to
  transition their calls. WQ_UNBOUND will be removed in a next release
  cycle"

* tag 'vfs-6.18-rc1.workqueue' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  fs: WQ_PERCPU added to alloc_workqueue users
  fs: replace use of system_wq with system_percpu_wq
  fs: replace use of system_unbound_wq with system_dfl_wq
2025-09-29 10:27:17 -07:00
Marco CrivellariandChristian Brauner 7a4f92d39f fs: replace use of system_unbound_wq with system_dfl_wq
Currently if a user enqueue a work item using schedule_delayed_work() the
used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use
WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to
schedule_work() that is using system_wq and queue_work(), that makes use
again of WORK_CPU_UNBOUND.

This lack of consistentcy cannot be addressed without refactoring the API.

system_unbound_wq should be the default workqueue so as not to enforce
locality constraints for random work whenever it's not required.

Adding system_dfl_wq to encourage its use when unbound work should be used.

The old system_unbound_wq will be kept for a few release cycles.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Link: https://lore.kernel.org/20250916082906.77439-2-marco.crivellari@suse.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19 16:15:07 +02:00
Lorenzo StoakesandAndrew Morton 39f8049cd4 mm: update coredump logic to correctly use bitmap mm flags
The coredump logic is slightly different from other users in that it both
stores mm flags and additionally sets and gets using masks.

Since the MMF_DUMPABLE_* flags must remain as they are for uABI reasons,
and of course these are within the first 32-bits of the flags, it is
reasonable to provide access to these in the same fashion so this logic
can all still keep working as it has been.

Therefore, introduce coredump-specific helpers __mm_flags_get_dumpable()
and __mm_flags_set_mask_dumpable() for this purpose, and update all core
dump users of mm flags to use these.

[lorenzo.stoakes@oracle.com: abstract set_mask_bits() invocation to mm_types.h to satisfy ARC]
  Link: https://lkml.kernel.org/r/0e7ad263-1ff7-446d-81fe-97cff9c0e7ed@lucifer.local
Link: https://lkml.kernel.org/r/2a5075f7e3c5b367d988178c79a3063d12ee53a9.1755012943.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: Mariano Pache <npache@redhat.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Namhyung kim <namhyung@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-13 16:54:57 -07:00
Christian Brauner be1e028302 coredump: don't pointlessly check and spew warnings
When a write happens it doesn't make sense to check perform checks on
the input. Skip them.

Whether a fixes tag is licensed is a bit of a gray area here but I'll
add one for the socket validation part I added recently.

Link: https://lore.kernel.org/20250821-moosbedeckt-denunziant-7908663f3563@brauner
Fixes: 16195d2c7d ("coredump: validate socket name as it is written")
Reported-by: Brad Spengler <brad.spengler@opensrcsec.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-08-21 13:54:40 +02:00
Dan CarpenterandChristian Brauner 589c12edcd coredump: Fix return value in coredump_parse()
The coredump_parse() function is bool type.  It should return true on
success and false on failure.  The cn_printf() returns zero on success
or negative error codes.  This mismatch means that when "return err;"
here, it is treated as success instead of failure.  Change it to return
false instead.

Fixes: a5715af549 ("coredump: make coredump_parse() return bool")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/aKRGu14w5vPSZLgv@stanley.mountain
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-08-19 13:51:28 +02:00
Linus Torvalds 672dcda246 Merge tag 'vfs-6.17-rc1.pidfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull pidfs updates from Christian Brauner:

 - persistent info

   Persist exit and coredump information independent of whether anyone
   currently holds a pidfd for the struct pid.

   The current scheme allocated pidfs dentries on-demand repeatedly.
   This scheme is reaching it's limits as it makes it impossible to pin
   information that needs to be available after the task has exited or
   coredumped and that should not be lost simply because the pidfd got
   closed temporarily. The next opener should still see the stashed
   information.

   This is also a prerequisite for supporting extended attributes on
   pidfds to allow attaching meta information to them.

   If someone opens a pidfd for a struct pid a pidfs dentry is allocated
   and stashed in pid->stashed. Once the last pidfd for the struct pid
   is closed the pidfs dentry is released and removed from pid->stashed.

   So if 10 callers create a pidfs dentry for the same struct pid
   sequentially, i.e., each closing the pidfd before the other creates a
   new one then a new pidfs dentry is allocated every time.

   Because multiple tasks acquiring and releasing a pidfd for the same
   struct pid can race with each another a task may still find a valid
   pidfs entry from the previous task in pid->stashed and reuse it. Or
   it might find a dead dentry in there and fail to reuse it and so
   stashes a new pidfs dentry. Multiple tasks may race to stash a new
   pidfs dentry but only one will succeed, the other ones will put their
   dentry.

   The current scheme aims to ensure that a pidfs dentry for a struct
   pid can only be created if the task is still alive or if a pidfs
   dentry already existed before the task was reaped and so exit
   information has been was stashed in the pidfs inode.

   That's great except that it's buggy. If a pidfs dentry is stashed in
   pid->stashed after pidfs_exit() but before __unhash_process() is
   called we will return a pidfd for a reaped task without exit
   information being available.

   The pidfds_pid_valid() check does not guard against this race as it
   doens't sync at all with pidfs_exit(). The pid_has_task() check might
   be successful simply because we're before __unhash_process() but
   after pidfs_exit().

   Introduce a new scheme where the lifetime of information associated
   with a pidfs entry (coredump and exit information) isn't bound to the
   lifetime of the pidfs inode but the struct pid itself.

   The first time a pidfs dentry is allocated for a struct pid a struct
   pidfs_attr will be allocated which will be used to store exit and
   coredump information.

   If all pidfs for the pidfs dentry are closed the dentry and inode can
   be cleaned up but the struct pidfs_attr will stick until the struct
   pid itself is freed. This will ensure minimal memory usage while
   persisting relevant information.

   The new scheme has various advantages. First, it allows to close the
   race where we end up handing out a pidfd for a reaped task for which
   no exit information is available. Second, it minimizes memory usage.
   Third, it allows to remove complex lifetime tracking via dentries
   when registering a struct pid with pidfs. There's no need to get or
   put a reference. Instead, the lifetime of exit and coredump
   information associated with a struct pid is bound to the lifetime of
   struct pid itself.

 - extended attributes

   Now that we have a way to persist information for pidfs dentries we
   can start supporting extended attributes on pidfds. This will allow
   userspace to attach meta information to tasks.

   One natural extension would be to introduce a custom pidfs.* extended
   attribute space and allow for the inheritance of extended attributes
   across fork() and exec().

   The first simple scheme will allow privileged userspace to set
   trusted extended attributes on pidfs inodes.

 - Allow autonomous pidfs file handles

   Various filesystems such as pidfs and drm support opening file
   handles without having to require a file descriptor to identify the
   filesystem. The filesystem are global single instances and can be
   trivially identified solely on the information encoded in the file
   handle.

   This makes it possible to not have to keep or acquire a sentinal file
   descriptor just to pass it to open_by_handle_at() to identify the
   filesystem. That's especially useful when such sentinel file
   descriptor cannot or should not be acquired.

   For pidfs this means a file handle can function as full replacement
   for storing a pid in a file. Instead a file handle can be stored and
   reopened purely based on the file handle.

   Such autonomous file handles can be opened with or without specifying
   a a file descriptor. If no proper file descriptor is used the
   FD_PIDFS_ROOT sentinel must be passed. This allows us to define
   further special negative fd sentinels in the future.

   Userspace can trivially test for support by trying to open the file
   handle with an invalid file descriptor.

 - Allow pidfds for reaped tasks with SCM_PIDFD messages

   This is a logical continuation of the earlier work to create pidfds
   for reaped tasks through the SO_PEERPIDFD socket option merged in
   923ea4d448 ("Merge patch series "net, pidfs: enable handing out
   pidfds for reaped sk->sk_peer_pid"").

 - Two minor fixes:

    * Fold fs_struct->{lock,seq} into a seqlock

    * Don't bother with path_{get,put}() in unix_open_file()

* tag 'vfs-6.17-rc1.pidfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (37 commits)
  don't bother with path_get()/path_put() in unix_open_file()
  fold fs_struct->{lock,seq} into a seqlock
  selftests: net: extend SCM_PIDFD test to cover stale pidfds
  af_unix: enable handing out pidfds for reaped tasks in SCM_PIDFD
  af_unix: stash pidfs dentry when needed
  af_unix/scm: fix whitespace errors
  af_unix: introduce and use scm_replace_pid() helper
  af_unix: introduce unix_skb_to_scm helper
  af_unix: rework unix_maybe_add_creds() to allow sleep
  selftests/pidfd: decode pidfd file handles withou having to specify an fd
  fhandle, pidfs: support open_by_handle_at() purely based on file handle
  uapi/fcntl: add FD_PIDFS_ROOT
  uapi/fcntl: add FD_INVALID
  fcntl/pidfd: redefine PIDFD_SELF_THREAD_GROUP
  uapi/fcntl: mark range as reserved
  fhandle: reflow get_path_anchor()
  pidfs: add pidfs_root_path() helper
  fhandle: rename to get_path_anchor()
  fhandle: hoist copy_from_user() above get_path_from_fd()
  fhandle: raise FILEID_IS_DIR in handle_type
  ...
2025-07-28 14:10:15 -07:00
Christian Brauner da9029b47d coredump: add coredump_skip() helper
Link: https://lore.kernel.org/20250612-work-coredump-massage-v1-24-315c0c34ba94@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-07 12:24:51 +02:00