Commit Graph

24281 Commits

Author SHA1 Message Date
Linus Torvalds
1b98f357da Merge tag 'net-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Paolo Abeni:
 "Core:

   - Implement the Device Memory TCP transmit path, allowing zero-copy
     data transmission on top of TCP from e.g. GPU memory to the wire.

   - Move all the IPv6 routing tables management outside the RTNL scope,
     under its own lock and RCU. The route control path is now 3x times
     faster.

   - Convert queue related netlink ops to instance lock, reducing again
     the scope of the RTNL lock. This improves the control plane
     scalability.

   - Refactor the software crc32c implementation, removing unneeded
     abstraction layers and improving significantly the related
     micro-benchmarks.

   - Optimize the GRO engine for UDP-tunneled traffic, for a 10%
     performance improvement in related stream tests.

   - Cover more per-CPU storage with local nested BH locking; this is a
     prep work to remove the current per-CPU lock in local_bh_disable()
     on PREMPT_RT.

   - Introduce and use nlmsg_payload helper, combining buffer bounds
     verification with accessing payload carried by netlink messages.

  Netfilter:

   - Rewrite the procfs conntrack table implementation, improving
     considerably the dump performance. A lot of user-space tools still
     use this interface.

   - Implement support for wildcard netdevice in netdev basechain and
     flowtables.

   - Integrate conntrack information into nft trace infrastructure.

   - Export set count and backend name to userspace, for better
     introspection.

  BPF:

   - BPF qdisc support: BPF-qdisc can be implemented with BPF struct_ops
     programs and can be controlled in similar way to traditional qdiscs
     using the "tc qdisc" command.

   - Refactor the UDP socket iterator, addressing long standing issues
     WRT duplicate hits or missed sockets.

  Protocols:

   - Improve TCP receive buffer auto-tuning and increase the default
     upper bound for the receive buffer; overall this improves the
     single flow maximum thoughput on 200Gbs link by over 60%.

   - Add AFS GSSAPI security class to AF_RXRPC; it provides transport
     security for connections to the AFS fileserver and VL server.

   - Improve TCP multipath routing, so that the sources address always
     matches the nexthop device.

   - Introduce SO_PASSRIGHTS for AF_UNIX, to allow disabling SCM_RIGHTS,
     and thus preventing DoS caused by passing around problematic FDs.

   - Retire DCCP socket. DCCP only receives updates for bugs, and major
     distros disable it by default. Its removal allows for better
     organisation of TCP fields to reduce the number of cache lines hit
     in the fast path.

   - Extend TCP drop-reason support to cover PAWS checks.

  Driver API:

   - Reorganize PTP ioctl flag support to require an explicit opt-in for
     the drivers, avoiding the problem of drivers not rejecting new
     unsupported flags.

   - Converted several device drivers to timestamping APIs.

   - Introduce per-PHY ethtool dump helpers, improving the support for
     dump operations targeting PHYs.

  Tests and tooling:

   - Add support for classic netlink in user space C codegen, so that
     ynl-c can now read, create and modify links, routes addresses and
     qdisc layer configuration.

   - Add ynl sub-types for binary attributes, allowing ynl-c to output
     known struct instead of raw binary data, clarifying the classic
     netlink output.

   - Extend MPTCP selftests to improve the code-coverage.

   - Add tests for XDP tail adjustment in AF_XDP.

  New hardware / drivers:

   - OpenVPN virtual driver: offload OpenVPN data channels processing to
     the kernel-space, increasing the data transfer throughput WRT the
     user-space implementation.

   - Renesas glue driver for the gigabit ethernet RZ/V2H(P) SoC.

   - Broadcom asp-v3.0 ethernet driver.

   - AMD Renoir ethernet device.

   - ReakTek MT9888 2.5G ethernet PHY driver.

   - Aeonsemi 10G C45 PHYs driver.

  Drivers:

   - Ethernet high-speed NICs:
       - nVidia/Mellanox (mlx5):
           - refactor the steering table handling to significantly
             reduce the amount of memory used
           - add support for complex matches in H/W flow steering
           - improve flow streeing error handling
           - convert to netdev instance locking
       - Intel (100G, ice, igb, ixgbe, idpf):
           - ice: add switchdev support for LLDP traffic over VF
           - ixgbe: add firmware manipulation and regions devlink support
           - igb: introduce support for frame transmission premption
           - igb: adds persistent NAPI configuration
           - idpf: introduce RDMA support
           - idpf: add initial PTP support
       - Meta (fbnic):
           - extend hardware stats coverage
           - add devlink dev flash support
       - Broadcom (bnxt):
           - add support for RX-side device memory TCP
       - Wangxun (txgbe):
           - implement support for udp tunnel offload
           - complete PTP and SRIOV support for AML 25G/10G devices

   - Ethernet NICs embedded and virtual:
       - Google (gve):
           - add device memory TCP TX support
       - Amazon (ena):
           - support persistent per-NAPI config
       - Airoha:
           - add H/W support for L2 traffic offload
           - add per flow stats for flow offloading
       - RealTek (rtl8211): add support for WoL magic packet
       - Synopsys (stmmac):
           - dwmac-socfpga 1000BaseX support
           - add Loongson-2K3000 support
           - introduce support for hardware-accelerated VLAN stripping
       - Broadcom (bcmgenet):
           - expose more H/W stats
       - Freescale (enetc, dpaa2-eth):
           - enetc: add MAC filter, VLAN filter RSS and loopback support
           - dpaa2-eth: convert to H/W timestamping APIs
       - vxlan: convert FDB table to rhashtable, for better scalabilty
       - veth: apply qdisc backpressure on full ring to reduce TX drops

   - Ethernet switches:
       - Microchip (kzZ88x3): add ETS scheduler support

   - Ethernet PHYs:
       - RealTek (rtl8211):
           - add support for WoL magic packet
           - add support for PHY LEDs

   - CAN:
       - Adds RZ/G3E CANFD support to the rcar_canfd driver.
       - Preparatory work for CAN-XL support.
       - Add self-tests framework with support for CAN physical interfaces.

   - WiFi:
       - mac80211:
           - scan improvements with multi-link operation (MLO)
       - Qualcomm (ath12k):
           - enable AHB support for IPQ5332
           - add monitor interface support to QCN9274
           - add multi-link operation support to WCN7850
           - add 802.11d scan offload support to WCN7850
           - monitor mode for WCN7850, better 6 GHz regulatory
       - Qualcomm (ath11k):
           - restore hibernation support
       - MediaTek (mt76):
           - WiFi-7 improvements
           - implement support for mt7990
       - Intel (iwlwifi):
           - enhanced multi-link single-radio (EMLSR) support on 5 GHz links
           - rework device configuration
       - RealTek (rtw88):
           - improve throughput for RTL8814AU
       - RealTek (rtw89):
           - add multi-link operation support
           - STA/P2P concurrency improvements
           - support different SAR configs by antenna

   - Bluetooth:
       - introduce HCI Driver protocol
       - btintel_pcie: do not generate coredump for diagnostic events
       - btusb: add HCI Drv commands for configuring altsetting
       - btusb: add RTL8851BE device 0x0bda:0xb850
       - btusb: add new VID/PID 13d3/3584 for MT7922
       - btusb: add new VID/PID 13d3/3630 and 13d3/3613 for MT7925
       - btnxpuart: implement host-wakeup feature"

* tag 'net-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1611 commits)
  selftests/bpf: Fix bpf selftest build warning
  selftests: netfilter: Fix skip of wildcard interface test
  net: phy: mscc: Stop clearing the the UDPv4 checksum for L2 frames
  net: openvswitch: Fix the dead loop of MPLS parse
  calipso: Don't call calipso functions for AF_INET sk.
  selftests/tc-testing: Add a test for HFSC eltree double add with reentrant enqueue behaviour on netem
  net_sched: hfsc: Address reentrant enqueue adding class to eltree twice
  octeontx2-pf: QOS: Refactor TC_HTB_LEAF_DEL_LAST callback
  octeontx2-pf: QOS: Perform cache sync on send queue teardown
  net: mana: Add support for Multi Vports on Bare metal
  net: devmem: ncdevmem: remove unused variable
  net: devmem: ksft: upgrade rx test to send 1K data
  net: devmem: ksft: add 5 tuple FS support
  net: devmem: ksft: add exit_wait to make rx test pass
  net: devmem: ksft: add ipv4 support
  net: devmem: preserve sockc_err
  page_pool: fix ugly page_pool formatting
  net: devmem: move list_add to net_devmem_bind_dmabuf.
  selftests: netfilter: nft_queue.sh: include file transfer duration in log message
  net: phy: mscc: Fix memory leak when using one step timestamping
  ...
2025-05-28 15:24:36 -07:00
Linus Torvalds
47cf96fbe3 Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
 "The headline feature is the re-enablement of support for Arm's
  Scalable Matrix Extension (SME) thanks to a bumper crop of fixes
  from Mark Rutland.

  If matrices aren't your thing, then Ryan's page-table optimisation
  work is much more interesting.

  Summary:

  ACPI, EFI and PSCI:

   - Decouple Arm's "Software Delegated Exception Interface" (SDEI)
     support from the ACPI GHES code so that it can be used by platforms
     booted with device-tree

   - Remove unnecessary per-CPU tracking of the FPSIMD state across EFI
     runtime calls

   - Fix a node refcount imbalance in the PSCI device-tree code

  CPU Features:

   - Ensure register sanitisation is applied to fields in ID_AA64MMFR4

   - Expose AIDR_EL1 to userspace via sysfs, primarily so that KVM
     guests can reliably query the underlying CPU types from the VMM

   - Re-enabling of SME support (CONFIG_ARM64_SME) as a result of fixes
     to our context-switching, signal handling and ptrace code

  Entry code:

   - Hook up TIF_NEED_RESCHED_LAZY so that CONFIG_PREEMPT_LAZY can be
     selected

  Memory management:

   - Prevent BSS exports from being used by the early PI code

   - Propagate level and stride information to the low-level TLB
     invalidation routines when operating on hugetlb entries

   - Use the page-table contiguous hint for vmap() mappings with
     VM_ALLOW_HUGE_VMAP where possible

   - Optimise vmalloc()/vmap() page-table updates to use "lazy MMU mode"
     and hook this up on arm64 so that the trailing DSB (used to publish
     the updates to the hardware walker) can be deferred until the end
     of the mapping operation

   - Extend mmap() randomisation for 52-bit virtual addresses (on par
     with 48-bit addressing) and remove limited support for
     randomisation of the linear map

  Perf and PMUs:

   - Add support for probing the CMN-S3 driver using ACPI

   - Minor driver fixes to the CMN, Arm-NI and amlogic PMU drivers

  Selftests:

   - Fix FPSIMD and SME tests to align with the freshly re-enabled SME
     support

   - Fix default setting of the OUTPUT variable so that tests are
     installed in the right location

  vDSO:

   - Replace raw counter access from inline assembly code with a call to
     the the __arch_counter_get_cntvct() helper function

  Miscellaneous:

   - Add some missing header inclusions to the CCA headers

   - Rework rendering of /proc/cpuinfo to follow the x86-approach and
     avoid repeated buffer expansion (the user-visible format remains
     identical)

   - Remove redundant selection of CONFIG_CRC32

   - Extend early error message when failing to map the device-tree
     blob"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (83 commits)
  arm64: cputype: Add cputype definition for HIP12
  arm64: el2_setup.h: Make __init_el2_fgt labels consistent, again
  perf/arm-cmn: Add CMN S3 ACPI binding
  arm64/boot: Disallow BSS exports to startup code
  arm64/boot: Move global CPU override variables out of BSS
  arm64/boot: Move init_pgdir[] and init_idmap_pgdir[] into __pi_ namespace
  perf/arm-cmn: Initialise cmn->cpu earlier
  kselftest/arm64: Set default OUTPUT path when undefined
  arm64: Update comment regarding values in __boot_cpu_mode
  arm64: mm: Drop redundant check in pmd_trans_huge()
  arm64/mm: Re-organise setting up FEAT_S1PIE registers PIRE0_EL1 and PIR_EL1
  arm64/mm: Permit lazy_mmu_mode to be nested
  arm64/mm: Disable barrier batching in interrupt contexts
  arm64/cpuinfo: only show one cpu's info in c_show()
  arm64/mm: Batch barriers when updating kernel mappings
  mm/vmalloc: Enter lazy mmu mode while manipulating vmalloc ptes
  arm64/mm: Support huge pte-mapped pages in vmap
  mm/vmalloc: Gracefully unmap huge ptes
  mm/vmalloc: Warn on improper use of vunmap_range()
  arm64/mm: Hoist barriers out of set_ptes_anysz() loop
  ...
2025-05-28 14:55:35 -07:00
Linus Torvalds
48cfc5791d Merge tag 'hardening-v6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull hardening updates from Kees Cook:

 - Update overflow helpers to ease refactoring of on-stack flex array
   instances (Gustavo A. R. Silva, Kees Cook)

 - lkdtm: Use SLAB_NO_MERGE instead of constructors (Harry Yoo)

 - Simplify CONFIG_CC_HAS_COUNTED_BY (Jan Hendrik Farr)

 - Disable u64 usercopy KUnit test on 32-bit SPARC (Thomas Weißschuh)

 - Add missed designated initializers now exposed by fixed randstruct
   (Nathan Chancellor, Kees Cook)

 - Document compilers versions for __builtin_dynamic_object_size

 - Remove ARM_SSP_PER_TASK GCC plugin

 - Fix GCC plugin randstruct, add selftests, and restore COMPILE_TEST
   builds

 - Kbuild: induce full rebuilds when dependencies change with GCC
   plugins, the Clang sanitizer .scl file, or the randstruct seed.

 - Kbuild: Switch from -Wvla to -Wvla-larger-than=1

 - Correct several __nonstring uses for -Wunterminated-string-initialization

* tag 'hardening-v6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (23 commits)
  Revert "hardening: Disable GCC randstruct for COMPILE_TEST"
  lib/tests: randstruct: Add deep function pointer layout test
  lib/tests: Add randstruct KUnit test
  randstruct: gcc-plugin: Remove bogus void member
  net: qede: Initialize qede_ll_ops with designated initializer
  scsi: qedf: Use designated initializer for struct qed_fcoe_cb_ops
  md/bcache: Mark __nonstring look-up table
  integer-wrap: Force full rebuild when .scl file changes
  randstruct: Force full rebuild when seed changes
  gcc-plugins: Force full rebuild when plugins change
  kbuild: Switch from -Wvla to -Wvla-larger-than=1
  hardening: simplify CONFIG_CC_HAS_COUNTED_BY
  overflow: Fix direct struct member initialization in _DEFINE_FLEX()
  kunit/overflow: Add tests for STACK_FLEX_ARRAY_SIZE() helper
  overflow: Add STACK_FLEX_ARRAY_SIZE() helper
  input/joystick: magellan: Mark __nonstring look-up table const
  watchdog: exar: Shorten identity name to fit correctly
  mod_devicetable: Enlarge the maximum platform_device_id name length
  overflow: Clarify expectations for getting DEFINE_FLEX variable sizes
  compiler_types: Identify compiler versions for __builtin_dynamic_object_size
  ...
2025-05-28 07:47:10 -07:00
Linus Torvalds
3b66e6b3c0 Merge tag 'cgroup-for-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:

 - cgroup rstat shared the tracking tree across all controllers with the
   rationale being that a cgroup which is using one resource is likely
   to be using other resources at the same time (ie. if something is
   allocating memory, it's probably consuming CPU cycles).

   However, this turned out to not scale very well especially with memcg
   using rstat for internal operations which made memcg stat read and
   flush patterns substantially different from other controllers. JP
   Kobryn split the rstat tree per controller.

 - cgroup BPF support was hooking into cgroup init/exit paths directly.

   Convert them to use a notifier chain instead so that other usages can
   be added easily. The two of the patches which implement this are
   mislabeled as belonging to sched_ext instead of cgroup. Sorry.

 - Relatively minor cpuset updates

 - Documentation updates

* tag 'cgroup-for-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (23 commits)
  sched_ext: Convert cgroup BPF support to use cgroup_lifetime_notifier
  sched_ext: Introduce cgroup_lifetime_notifier
  cgroup: Minor reorganization of cgroup_create()
  cgroup, docs: cpu controller's interaction with various scheduling policies
  cgroup, docs: convert space indentation to tab indentation
  cgroup: avoid per-cpu allocation of size zero rstat cpu locks
  cgroup, docs: be specific about bandwidth control of rt processes
  cgroup: document the rstat per-cpu initialization
  cgroup: helper for checking rstat participation of css
  cgroup: use subsystem-specific rstat locks to avoid contention
  cgroup: use separate rstat trees for each subsystem
  cgroup: compare css to cgroup::self in helper for distingushing css
  cgroup: warn on rstat usage by early init subsystems
  cgroup/cpuset: drop useless cpumask_empty() in compute_effective_exclusive_cpumask()
  cgroup/rstat: Improve cgroup_rstat_push_children() documentation
  cgroup: fix goto ordering in cgroup_init()
  cgroup: fix pointer check in css_rstat_init()
  cgroup/cpuset: Add warnings to catch inconsistency in exclusive CPUs
  cgroup/cpuset: Fix obsolete comment in cpuset_css_offline()
  cgroup/cpuset: Always use cpu_active_mask
  ...
2025-05-27 20:59:53 -07:00
Linus Torvalds
b3570b00dc Merge tag 'locking-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
 "Futexes:

   - Add support for task local hash maps (Sebastian Andrzej Siewior,
     Peter Zijlstra)

   - Implement the FUTEX2_NUMA ABI, which feature extends the futex
     interface to be NUMA-aware. On NUMA-aware futexes a second u32 word
     containing the NUMA node is added to after the u32 futex value word
     (Peter Zijlstra)

   - Implement the FUTEX2_MPOL ABI, which feature extends the futex
     interface to be mempolicy-aware as well, to further refine futex
     node mappings and lookups (Peter Zijlstra)

  Locking primitives:

   - Misc cleanups (Andy Shevchenko, Borislav Petkov, Colin Ian King,
     Ingo Molnar, Nam Cao, Peter Zijlstra)

  Lockdep:

   - Prevent abuse of lockdep subclasses (Waiman Long)

   - Add number of dynamic keys to /proc/lockdep_stats (Waiman Long)

  Plus misc cleanups and fixes"

* tag 'locking-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits)
  selftests/futex: Fix spelling mistake "unitiliazed" -> "uninitialized"
  futex: Correct the kernedoc return value for futex_wait_setup().
  tools headers: Synchronize prctl.h ABI header
  futex: Use RCU_INIT_POINTER() in futex_mm_init().
  selftests/futex: Use TAP output in futex_numa_mpol
  selftests/futex: Use TAP output in futex_priv_hash
  futex: Fix kernel-doc comments
  futex: Relax the rcu_assign_pointer() assignment of mm->futex_phash in futex_mm_init()
  futex: Fix outdated comment in struct restart_block
  locking/lockdep: Add number of dynamic keys to /proc/lockdep_stats
  locking/lockdep: Prevent abuse of lockdep subclass
  locking/lockdep: Move hlock_equal() to the respective #ifdeffery
  futex,selftests: Add another FUTEX2_NUMA selftest
  selftests/futex: Add futex_numa_mpol
  selftests/futex: Add futex_priv_hash
  selftests/futex: Build without headers nonsense
  tools/perf: Allow to select the number of hash buckets
  tools headers: Synchronize prctl.h ABI header
  futex: Implement FUTEX2_MPOL
  futex: Implement FUTEX2_NUMA
  ...
2025-05-26 14:42:07 -07:00
Linus Torvalds
6f59de9bc0 Merge tag 'for-6.16/block-20250523' of git://git.kernel.dk/linux
Pull block updates from Jens Axboe:

 - ublk updates:
      - Add support for updating the size of a ublk instance
      - Zero-copy improvements
      - Auto-registering of buffers for zero-copy
      - Series simplifying and improving GET_DATA and request lookup
      - Series adding quiesce support
      - Lots of selftests additions
      - Various cleanups

 - NVMe updates via Christoph:
      - add per-node DMA pools and use them for PRP/SGL allocations
        (Caleb Sander Mateos, Keith Busch)
      - nvme-fcloop refcounting fixes (Daniel Wagner)
      - support delayed removal of the multipath node and optionally
        support the multipath node for private namespaces (Nilay Shroff)
      - support shared CQs in the PCI endpoint target code (Wilfred
        Mallawa)
      - support admin-queue only authentication (Hannes Reinecke)
      - use the crc32c library instead of the crypto API (Eric Biggers)
      - misc cleanups (Christoph Hellwig, Marcelo Moreira, Hannes
        Reinecke, Leon Romanovsky, Gustavo A. R. Silva)

 - MD updates via Yu:
      - Fix that normal IO can be starved by sync IO, found by mkfs on
        newly created large raid5, with some clean up patches for bdev
        inflight counters

 - Clean up brd, getting rid of atomic kmaps and bvec poking

 - Add loop driver specifically for zoned IO testing

 - Eliminate blk-rq-qos calls with a static key, if not enabled

 - Improve hctx locking for when a plug has IO for multiple queues
   pending

 - Remove block layer bouncing support, which in turn means we can
   remove the per-node bounce stat as well

 - Improve blk-throttle support

 - Improve delay support for blk-throttle

 - Improve brd discard support

 - Unify IO scheduler switching. This should also fix a bunch of lockdep
   warnings we've been seeing, after enabling lockdep support for queue
   freezing/unfreezeing

 - Add support for block write streams via FDP (flexible data placement)
   on NVMe

 - Add a bunch of block helpers, facilitating the removal of a bunch of
   duplicated boilerplate code

 - Remove obsolete BLK_MQ pci and virtio Kconfig options

 - Add atomic/untorn write support to blktrace

 - Various little cleanups and fixes

* tag 'for-6.16/block-20250523' of git://git.kernel.dk/linux: (186 commits)
  selftests: ublk: add test for UBLK_F_QUIESCE
  ublk: add feature UBLK_F_QUIESCE
  selftests: ublk: add test case for UBLK_U_CMD_UPDATE_SIZE
  traceevent/block: Add REQ_ATOMIC flag to block trace events
  ublk: run auto buf unregisgering in same io_ring_ctx with registering
  io_uring: add helper io_uring_cmd_ctx_handle()
  ublk: remove io argument from ublk_auto_buf_reg_fallback()
  ublk: handle ublk_set_auto_buf_reg() failure correctly in ublk_fetch()
  selftests: ublk: add test for covering UBLK_AUTO_BUF_REG_FALLBACK
  selftests: ublk: support UBLK_F_AUTO_BUF_REG
  ublk: support UBLK_AUTO_BUF_REG_FALLBACK
  ublk: register buffer to local io_uring with provided buf index via UBLK_F_AUTO_BUF_REG
  ublk: prepare for supporting to register request buffer automatically
  ublk: convert to refcount_t
  selftests: ublk: make IO & device removal test more stressful
  nvme: rename nvme_mpath_shutdown_disk to nvme_mpath_remove_disk
  nvme: introduce multipath_always_on module param
  nvme-multipath: introduce delayed removal of the multipath head node
  nvme-pci: derive and better document max segments limits
  nvme-pci: use struct_size for allocation struct nvme_dev
  ...
2025-05-26 11:39:36 -07:00
Linus Torvalds
181d8e399f Merge tag 'vfs-6.16-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner:
 "This contains the usual selections of misc updates for this cycle.

  Features:

   - Use folios for symlinks in the page cache

     FUSE already uses folios for its symlinks. Mirror that conversion
     in the generic code and the NFS code. That lets us get rid of a few
     folio->page->folio conversions in this path, and some of the few
     remaining users of read_cache_page() / read_mapping_page()

   - Try and make a few filesystem operations killable on the VFS
     inode->i_mutex level

   - Add sysctl vfs_cache_pressure_denom for bulk file operations

     Some workloads need to preserve more dentries than we currently
     allow through out sysctl interface

     A HDFS servers with 12 HDDs per server, on a HDFS datanode startup
     involves scanning all files and caching their metadata (including
     dentries and inodes) in memory. Each HDD contains approximately 2
     million files, resulting in a total of ~20 million cached dentries
     after initialization

     To minimize dentry reclamation, they set vfs_cache_pressure to 1.
     Despite this configuration, memory pressure conditions can still
     trigger reclamation of up to 50% of cached dentries, reducing the
     cache from 20 million to approximately 10 million entries. During
     the subsequent cache rebuild period, any HDFS datanode restart
     operation incurs substantial latency penalties until full cache
     recovery completes

     To maintain service stability, more dentries need to be preserved
     during memory reclamation. The current minimum reclaim ratio (1/100
     of total dentries) remains too aggressive for such workload. This
     patch introduces vfs_cache_pressure_denom for more granular cache
     pressure control

     The configuration [vfs_cache_pressure=1,
     vfs_cache_pressure_denom=10000] effectively maintains the full 20
     million dentry cache under memory pressure, preventing datanode
     restart performance degradation

   - Avoid some jumps in inode_permission() using likely()/unlikely()

   - Avid a memory access which is most likely a cache miss when
     descending into devcgroup_inode_permission()

   - Add fastpath predicts for stat() and fdput()

   - Anonymous inodes currently don't come with a proper mode causing
     issues in the kernel when we want to add useful VFS debug assert.
     Fix that by giving them a proper mode and masking it off when we
     report it to userspace which relies on them not having any mode

   - Anonymous inodes currently allow to change inode attributes because
     the VFS falls back to simple_setattr() if i_op->setattr isn't
     implemented. This means the ownership and mode for every single
     user of anon_inode_inode can be changed. Block that as it's either
     useless or actively harmful. If specific ownership is needed the
     respective subsystem should allocate anonymous inodes from their
     own private superblock

   - Raise SB_I_NODEV and SB_I_NOEXEC on the anonymous inode superblock

   - Add proper tests for anonymous inode behavior

   - Make it easy to detect proper anonymous inodes and to ensure that
     we can detect them in codepaths such as readahead()

  Cleanups:

   - Port pidfs to the new anon_inode_{g,s}etattr() helpers

   - Try to remove the uselib() system call

   - Add unlikely branch hint return path for poll

   - Add unlikely branch hint on return path for core_sys_select

   - Don't allow signals to interrupt getdents copying for fuse

   - Provide a size hint to dir_context for during readdir()

   - Use writeback_iter directly in mpage_writepages

   - Update compression and mtime descriptions in initramfs
     documentation

   - Update main netfs API document

   - Remove useless plus one in super_cache_scan()

   - Remove unnecessary NULL-check guards during setns()

   - Add separate separate {get,put}_cgroup_ns no-op cases

  Fixes:

   - Fix typo in root= kernel parameter description

   - Use KERN_INFO for infof()|info_plog()|infofc()

   - Correct comments of fs_validate_description()

   - Mark an unlikely if condition with unlikely() in
     vfs_parse_monolithic_sep()

   - Delete macro fsparam_u32hex()

   - Remove unused and problematic validate_constant_table()

   - Fix potential unsigned integer underflow in fs_name()

   - Make file-nr output the total allocated file handles"

* tag 'vfs-6.16-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (43 commits)
  fs: Pass a folio to page_put_link()
  nfs: Use a folio in nfs_get_link()
  fs: Convert __page_get_link() to use a folio
  fs/read_write: make default_llseek() killable
  fs/open: make do_truncate() killable
  fs/open: make chmod_common() and chown_common() killable
  include/linux/fs.h: add inode_lock_killable()
  readdir: supply dir_context.count as readdir buffer size hint
  vfs: Add sysctl vfs_cache_pressure_denom for bulk file operations
  fuse: don't allow signals to interrupt getdents copying
  Documentation: fix typo in root= kernel parameter description
  include/cgroup: separate {get,put}_cgroup_ns no-op case
  kernel/nsproxy: remove unnecessary guards
  fs: use writeback_iter directly in mpage_writepages
  fs: remove useless plus one in super_cache_scan()
  fs: add S_ANON_INODE
  fs: remove uselib() system call
  device_cgroup: avoid access to ->i_rdev in the common case in devcgroup_inode_permission()
  fs/fs_parse: Remove unused and problematic validate_constant_table()
  fs: touch up predicts in inode_permission()
  ...
2025-05-26 09:02:39 -07:00
Linus Torvalds
dc76285144 Merge tag 'vfs-6.16-rc1.writepage' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull final writepage conversion from Christian Brauner:
 "This converts vboxfs from ->writepage() to ->writepages().

  This was the last user of the ->writepage() method. So remove
  ->writepage() completely and all references to it"

* tag 'vfs-6.16-rc1.writepage' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  fs: Remove aops->writepage
  mm: Remove swap_writepage() and shmem_writepage()
  ttm: Call shmem_writeout() from ttm_backup_backup_page()
  i915: Use writeback_iter()
  shmem: Add shmem_writeout()
  writeback: Remove writeback_use_writepage()
  migrate: Remove call to ->writepage
  vboxsf: Convert to writepages
  9p: Add a migrate_folio method
2025-05-26 08:23:09 -07:00
Linus Torvalds
0f8c0258bf Merge tag 'mm-hotfixes-stable-2025-05-25-00-58' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull hotfixes from Andrew Morton:
 "22 hotfixes.

  13 are cc:stable and the remainder address post-6.14 issues or aren't
  considered necessary for -stable kernels. 19 are for MM"

* tag 'mm-hotfixes-stable-2025-05-25-00-58' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (22 commits)
  mailmap: add Jarkko's employer email address
  mm: fix copy_vma() error handling for hugetlb mappings
  memcg: always call cond_resched() after fn()
  mm/hugetlb: fix kernel NULL pointer dereference when replacing free hugetlb folios
  mm: vmalloc: only zero-init on vrealloc shrink
  mm: vmalloc: actually use the in-place vrealloc region
  alloc_tag: allocate percpu counters for module tags dynamically
  module: release codetag section when module load fails
  mm/cma: make detection of highmem_start more robust
  MAINTAINERS: add mm memory policy section
  MAINTAINERS: add mm ksm section
  kasan: avoid sleepable page allocation from atomic context
  highmem: add folio_test_partial_kmap()
  MAINTAINERS: add hung-task detector section
  taskstats: fix struct taskstats breaks backward compatibility since version 15
  mm/truncate: fix out-of-bounds when doing a right-aligned split
  MAINTAINERS: add mm reclaim section
  MAINTAINERS: update page allocator section
  mm: fix VM_UFFD_MINOR == VM_SHADOW_STACK on USERFAULTFD=y && ARM64_GCS=y
  mm: mmap: map MAP_STACK to VM_NOHUGEPAGE only if THP is enabled
  ...
2025-05-25 07:48:35 -07:00
Ingo Molnar
94ec70880f Merge branch 'locking/futex' into locking/core, to pick up pending futex changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-05-25 10:10:08 +02:00
Ricardo Cañuelo Navarro
ee40c9920a mm: fix copy_vma() error handling for hugetlb mappings
If, during a mremap() operation for a hugetlb-backed memory mapping,
copy_vma() fails after the source vma has been duplicated and opened (ie. 
vma_link() fails), the error is handled by closing the new vma.  This
updates the hugetlbfs reservation counter of the reservation map which at
this point is referenced by both the source vma and the new copy.  As a
result, once the new vma has been freed and copy_vma() returns, the
reservation counter for the source vma will be incorrect.

This patch addresses this corner case by clearing the hugetlb private page
reservation reference for the new vma and decrementing the reference
before closing the vma, so that vma_close() won't update the reservation
counter.  This is also what copy_vma_and_data() does with the source vma
if copy_vma() succeeds, so a helper function has been added to do the
fixup in both functions.

The issue was reported by a private syzbot instance and can be reproduced
using the C reproducer in [1].  It's also a possible duplicate of public
syzbot report [2].  The WARNING report is:

============================================================
page_counter underflow: -1024 nr_pages=1024
WARNING: CPU: 0 PID: 3287 at mm/page_counter.c:61 page_counter_cancel+0xf6/0x120
Modules linked in:
CPU: 0 UID: 0 PID: 3287 Comm: repro__WARNING_ Not tainted 6.15.0-rc7+ #54 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-2-gc13ff2cd-prebuilt.qemu.org 04/01/2014
RIP: 0010:page_counter_cancel+0xf6/0x120
Code: ff 5b 41 5e 41 5f 5d c3 cc cc cc cc e8 f3 4f 8f ff c6 05 64 01 27 06 01 48 c7 c7 60 15 f8 85 48 89 de 4c 89 fa e8 2a a7 51 ff <0f> 0b e9 66 ff ff ff 44 89 f9 80 e1 07 38 c1 7c 9d 4c 81
RSP: 0018:ffffc900025df6a0 EFLAGS: 00010246
RAX: 2edfc409ebb44e00 RBX: fffffffffffffc00 RCX: ffff8880155f0000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff81c4a23c R09: 1ffff1100330482a
R10: dffffc0000000000 R11: ffffed100330482b R12: 0000000000000000
R13: ffff888058a882c0 R14: ffff888058a882c0 R15: 0000000000000400
FS:  0000000000000000(0000) GS:ffff88808fc53000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004b33e0 CR3: 00000000076d6000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 page_counter_uncharge+0x33/0x80
 hugetlb_cgroup_uncharge_counter+0xcb/0x120
 hugetlb_vm_op_close+0x579/0x960
 ? __pfx_hugetlb_vm_op_close+0x10/0x10
 remove_vma+0x88/0x130
 exit_mmap+0x71e/0xe00
 ? __pfx_exit_mmap+0x10/0x10
 ? __mutex_unlock_slowpath+0x22e/0x7f0
 ? __pfx_exit_aio+0x10/0x10
 ? __up_read+0x256/0x690
 ? uprobe_clear_state+0x274/0x290
 ? mm_update_next_owner+0xa9/0x810
 __mmput+0xc9/0x370
 exit_mm+0x203/0x2f0
 ? __pfx_exit_mm+0x10/0x10
 ? taskstats_exit+0x32b/0xa60
 do_exit+0x921/0x2740
 ? do_raw_spin_lock+0x155/0x3b0
 ? __pfx_do_exit+0x10/0x10
 ? __pfx_do_raw_spin_lock+0x10/0x10
 ? _raw_spin_lock_irq+0xc5/0x100
 do_group_exit+0x20c/0x2c0
 get_signal+0x168c/0x1720
 ? __pfx_get_signal+0x10/0x10
 ? schedule+0x165/0x360
 arch_do_signal_or_restart+0x8e/0x7d0
 ? __pfx_arch_do_signal_or_restart+0x10/0x10
 ? __pfx___se_sys_futex+0x10/0x10
 syscall_exit_to_user_mode+0xb8/0x2c0
 do_syscall_64+0x75/0x120
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x422dcd
Code: Unable to access opcode bytes at 0x422da3.
RSP: 002b:00007ff266cdb208 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007ff266cdbcdc RCX: 0000000000422dcd
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00000000004c7bec
RBP: 00007ff266cdb220 R08: 203a6362696c6720 R09: 203a6362696c6720
R10: 0000200000c00000 R11: 0000000000000246 R12: ffffffffffffffd0
R13: 0000000000000002 R14: 00007ffe1cb5f520 R15: 00007ff266cbb000
 </TASK>
============================================================

Link: https://lkml.kernel.org/r/20250523-warning_in_page_counter_cancel-v2-1-b6df1a8cfefd@igalia.com
Link: https://people.igalia.com/rcn/kernel_logs/20250422__WARNING_in_page_counter_cancel__repro.c [1]
Link: https://lore.kernel.org/all/67000a50.050a0220.49194.048d.GAE@google.com/ [2]
Signed-off-by: Ricardo Cañuelo Navarro <rcn@igalia.com>
Suggested-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Florent Revest <revest@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-25 00:53:49 -07:00
Breno Leitao
06717a7b6c memcg: always call cond_resched() after fn()
I am seeing soft lockup on certain machine types when a cgroup OOMs.  This
is happening because killing the process in certain machine might be very
slow, which causes the soft lockup and RCU stalls.  This happens usually
when the cgroup has MANY processes and memory.oom.group is set.

Example I am seeing in real production:

       [462012.244552] Memory cgroup out of memory: Killed process 3370438 (crosvm) ....
       ....
       [462037.318059] Memory cgroup out of memory: Killed process 4171372 (adb) ....
       [462037.348314] watchdog: BUG: soft lockup - CPU#64 stuck for 26s! [stat_manager-ag:1618982]
       ....

Quick look at why this is so slow, it seems to be related to serial flush
for certain machine types.  For all the crashes I saw, the target CPU was
at console_flush_all().

In the case above, there are thousands of processes in the cgroup, and it
is soft locking up before it reaches the 1024 limit in the code (which
would call the cond_resched()).  So, cond_resched() in 1024 blocks is not
sufficient.

Remove the counter-based conditional rescheduling logic and call
cond_resched() unconditionally after each task iteration, after fn() is
called.  This avoids the lockup independently of how slow fn() is.

Link: https://lkml.kernel.org/r/20250523-memcg_fix-v1-1-ad3eafb60477@debian.org
Fixes: ade81479c7 ("memcg: fix soft lockup in the OOM process")
Signed-off-by: Breno Leitao <leitao@debian.org>
Suggested-by: Rik van Riel <riel@surriel.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Michael van der Westhuizen <rmikey@meta.com>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Chen Ridong <chenridong@huawei.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-25 00:53:49 -07:00
Ge Yang
113ed54ad2 mm/hugetlb: fix kernel NULL pointer dereference when replacing free hugetlb folios
A kernel crash was observed when replacing free hugetlb folios:

BUG: kernel NULL pointer dereference, address: 0000000000000028
PGD 0 P4D 0
Oops: Oops: 0000 [#1] SMP NOPTI
CPU: 28 UID: 0 PID: 29639 Comm: test_cma.sh Tainted 6.15.0-rc6-zp #41 PREEMPT(voluntary)
RIP: 0010:alloc_and_dissolve_hugetlb_folio+0x1d/0x1f0
RSP: 0018:ffffc9000b30fa90 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000342cca RCX: ffffea0043000000
RDX: ffffc9000b30fb08 RSI: ffffea0043000000 RDI: 0000000000000000
RBP: ffffc9000b30fb20 R08: 0000000000001000 R09: 0000000000000000
R10: ffff88886f92eb00 R11: 0000000000000000 R12: ffffea0043000000
R13: 0000000000000000 R14: 00000000010c0200 R15: 0000000000000004
FS:  00007fcda5f14740(0000) GS:ffff8888ec1d8000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000028 CR3: 0000000391402000 CR4: 0000000000350ef0
Call Trace:
<TASK>
 replace_free_hugepage_folios+0xb6/0x100
 alloc_contig_range_noprof+0x18a/0x590
 ? srso_return_thunk+0x5/0x5f
 ? down_read+0x12/0xa0
 ? srso_return_thunk+0x5/0x5f
 cma_range_alloc.constprop.0+0x131/0x290
 __cma_alloc+0xcf/0x2c0
 cma_alloc_write+0x43/0xb0
 simple_attr_write_xsigned.constprop.0.isra.0+0xb2/0x110
 debugfs_attr_write+0x46/0x70
 full_proxy_write+0x62/0xa0
 vfs_write+0xf8/0x420
 ? srso_return_thunk+0x5/0x5f
 ? filp_flush+0x86/0xa0
 ? srso_return_thunk+0x5/0x5f
 ? filp_close+0x1f/0x30
 ? srso_return_thunk+0x5/0x5f
 ? do_dup2+0xaf/0x160
 ? srso_return_thunk+0x5/0x5f
 ksys_write+0x65/0xe0
 do_syscall_64+0x64/0x170
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

There is a potential race between __update_and_free_hugetlb_folio() and
replace_free_hugepage_folios():

CPU1                              CPU2
__update_and_free_hugetlb_folio   replace_free_hugepage_folios
                                    folio_test_hugetlb(folio)
                                    -- It's still hugetlb folio.

  __folio_clear_hugetlb(folio)
  hugetlb_free_folio(folio)
                                    h = folio_hstate(folio)
                                    -- Here, h is NULL pointer

When the above race condition occurs, folio_hstate(folio) returns NULL,
and subsequent access to this NULL pointer will cause the system to crash.
To resolve this issue, execute folio_hstate(folio) under the protection
of the hugetlb_lock lock, ensuring that folio_hstate(folio) does not
return NULL.

Link: https://lkml.kernel.org/r/1747884137-26685-1-git-send-email-yangge1116@126.com
Fixes: 04f13d241b ("mm: replace free hugepage folios after migration")
Signed-off-by: Ge Yang <yangge1116@126.com>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <21cnbao@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-25 00:53:48 -07:00
Kees Cook
70d1eb031a mm: vmalloc: only zero-init on vrealloc shrink
The common case is to grow reallocations, and since init_on_alloc will
have already zeroed the whole allocation, we only need to zero when
shrinking the allocation.

Link: https://lkml.kernel.org/r/20250515214217.619685-2-kees@kernel.org
Fixes: a0309faf1c ("mm: vmalloc: support more granular vrealloc() sizing")
Signed-off-by: Kees Cook <kees@kernel.org>
Tested-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: "Erhard F." <erhard_f@mailbox.org>
Cc: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-25 00:53:48 -07:00
Kees Cook
f7a35a3c36 mm: vmalloc: actually use the in-place vrealloc region
Patch series "mm: vmalloc: Actually use the in-place vrealloc region".

This fixes a performance regression[1] with vrealloc()[1].


The refactoring to not build a new vmalloc region only actually worked
when shrinking.  Actually return the resized area when it grows.  Ugh.

Link: https://lkml.kernel.org/r/20250515214217.619685-1-kees@kernel.org
Fixes: a0309faf1c ("mm: vmalloc: support more granular vrealloc() sizing")
Signed-off-by: Kees Cook <kees@kernel.org>
Reported-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Closes: https://lore.kernel.org/all/20250515-bpf-verifier-slowdown-vwo2meju4cgp2su5ckj@6gi6ssxbnfqg [1]
Tested-by: Eduard Zingerman <eddyz87@gmail.com>
Tested-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Tested-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Reviewed-by: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Cc: "Erhard F." <erhard_f@mailbox.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-25 00:53:48 -07:00
Mike Rapoport (Microsoft)
07c9214c79 mm/cma: make detection of highmem_start more robust
Pratyush Yadav reports the following crash:

    ------------[ cut here ]------------
    kernel BUG at arch/x86/mm/physaddr.c:23!
    ception 0x06 IP 10:ffffffff812ebbf8 error 0 cr2 0xffff88903ffff000
    CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.15.0-rc6+ #231 PREEMPT(undef)
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014
    RIP: 0010:__phys_addr+0x58/0x60
    Code: 01 48 89 c2 48 d3 ea 48 85 d2 75 05 e9 91 52 cf 00 0f 0b 48 3d ff ff ff 1f 77 0f 48 8b 05 20 54 55 01 48 01 d0 e9 78 52 cf 00 <0f> 0b 90 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90
    RSP: 0000:ffffffff82803dd8 EFLAGS: 00010006 ORIG_RAX: 0000000000000000
    RAX: 000000007fffffff RBX: 00000000ffffffff RCX: 0000000000000000
    RDX: 000000007fffffff RSI: 0000000280000000 RDI: ffffffffffffffff
    RBP: ffffffff82803e68 R08: 0000000000000000 R09: 0000000000000000
    R10: ffffffff83153180 R11: ffffffff82803e48 R12: ffffffff83c9aed0
    R13: 0000000000000000 R14: 0000001040000000 R15: 0000000000000000
    FS:  0000000000000000(0000) GS:0000000000000000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: ffff88903ffff000 CR3: 0000000002838000 CR4: 00000000000000b0
    Call Trace:
     <TASK>
     ? __cma_declare_contiguous_nid+0x6e/0x340
     ? cma_declare_contiguous_nid+0x33/0x70
     ? dma_contiguous_reserve_area+0x2f/0x70
     ? setup_arch+0x6f1/0x870
     ? start_kernel+0x52/0x4b0
     ? x86_64_start_reservations+0x29/0x30
     ? x86_64_start_kernel+0x7c/0x80
     ? common_startup_64+0x13e/0x141

  The reason is that __cma_declare_contiguous_nid() does:

          highmem_start = __pa(high_memory - 1) + 1;

  If dma_contiguous_reserve_area() (or any other CMA declaration) is
  called before free_area_init(), high_memory is uninitialized. Without
  CONFIG_DEBUG_VIRTUAL, it will likely work but use the wrong value for
  highmem_start.

The issue occurs because commit e120d1bc12 ("arch, mm: set high_memory
in free_area_init()") moved initialization of high_memory after the call
to dma_contiguous_reserve() -> __cma_declare_contiguous_nid() on several
architectures.

In the case CONFIG_HIGHMEM is enabled, some architectures that actually
support HIGHMEM (arm, powerpc and x86) have initialization of high_memory
before a possible call to __cma_declare_contiguous_nid() and some
initialized high_memory late anyway (arc, csky, microblase, mips, sparc,
xtensa) even before the commit e120d1bc12 so they are fine with using
uninitialized value of high_memory.

And in the case CONFIG_HIGHMEM is disabled high_memory essentially becomes
the first address after memory end, so instead of relying on high_memory
to calculate highmem_start use memblock_end_of_DRAM() and eliminate the
dependency of CMA area creation on high_memory in majority of
configurations.

Link: https://lkml.kernel.org/r/20250519171805.1288393-1-rppt@kernel.org
Fixes: e120d1bc12 ("arch, mm: set high_memory in free_area_init()")
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reported-by: Pratyush Yadav <ptyadav@amazon.de>
Tested-by: Pratyush Yadav <ptyadav@amazon.de>
Tested-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-25 00:53:47 -07:00
Jakub Kicinski
33e1b1b399 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-6.15-rc8).

Conflicts:
  80f2ab46c2 ("irdma: free iwdev->rf after removing MSI-X")
  4bcc063939 ("ice, irdma: fix an off by one in error handling code")
  c24a65b6a2 ("iidc/ice/irdma: Update IDC to support multiple consumers")
https://lore.kernel.org/20250513130630.280ee6c5@canb.auug.org.au

No extra adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-22 09:42:41 -07:00
Alexander Gordeev
b6ea95a34c kasan: avoid sleepable page allocation from atomic context
apply_to_pte_range() enters the lazy MMU mode and then invokes
kasan_populate_vmalloc_pte() callback on each page table walk iteration. 
However, the callback can go into sleep when trying to allocate a single
page, e.g.  if an architecutre disables preemption on lazy MMU mode enter.

On s390 if make arch_enter_lazy_mmu_mode() -> preempt_enable() and
arch_leave_lazy_mmu_mode() -> preempt_disable(), such crash occurs:

[    0.663336] BUG: sleeping function called from invalid context at ./include/linux/sched/mm.h:321
[    0.663348] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2, name: kthreadd
[    0.663358] preempt_count: 1, expected: 0
[    0.663366] RCU nest depth: 0, expected: 0
[    0.663375] no locks held by kthreadd/2.
[    0.663383] Preemption disabled at:
[    0.663386] [<0002f3284cbb4eda>] apply_to_pte_range+0xfa/0x4a0
[    0.663405] CPU: 0 UID: 0 PID: 2 Comm: kthreadd Not tainted 6.15.0-rc5-gcc-kasan-00043-gd76bb1ebb558-dirty #162 PREEMPT
[    0.663408] Hardware name: IBM 3931 A01 701 (KVM/Linux)
[    0.663409] Call Trace:
[    0.663410]  [<0002f3284c385f58>] dump_stack_lvl+0xe8/0x140
[    0.663413]  [<0002f3284c507b9e>] __might_resched+0x66e/0x700
[    0.663415]  [<0002f3284cc4f6c0>] __alloc_frozen_pages_noprof+0x370/0x4b0
[    0.663419]  [<0002f3284ccc73c0>] alloc_pages_mpol+0x1a0/0x4a0
[    0.663421]  [<0002f3284ccc8518>] alloc_frozen_pages_noprof+0x88/0xc0
[    0.663424]  [<0002f3284ccc8572>] alloc_pages_noprof+0x22/0x120
[    0.663427]  [<0002f3284cc341ac>] get_free_pages_noprof+0x2c/0xc0
[    0.663429]  [<0002f3284cceba70>] kasan_populate_vmalloc_pte+0x50/0x120
[    0.663433]  [<0002f3284cbb4ef8>] apply_to_pte_range+0x118/0x4a0
[    0.663435]  [<0002f3284cbc7c14>] apply_to_pmd_range+0x194/0x3e0
[    0.663437]  [<0002f3284cbc99be>] __apply_to_page_range+0x2fe/0x7a0
[    0.663440]  [<0002f3284cbc9e88>] apply_to_page_range+0x28/0x40
[    0.663442]  [<0002f3284ccebf12>] kasan_populate_vmalloc+0x82/0xa0
[    0.663445]  [<0002f3284cc1578c>] alloc_vmap_area+0x34c/0xc10
[    0.663448]  [<0002f3284cc1c2a6>] __get_vm_area_node+0x186/0x2a0
[    0.663451]  [<0002f3284cc1e696>] __vmalloc_node_range_noprof+0x116/0x310
[    0.663454]  [<0002f3284cc1d950>] __vmalloc_node_noprof+0xd0/0x110
[    0.663457]  [<0002f3284c454b88>] alloc_thread_stack_node+0xf8/0x330
[    0.663460]  [<0002f3284c458d56>] dup_task_struct+0x66/0x4d0
[    0.663463]  [<0002f3284c45be90>] copy_process+0x280/0x4b90
[    0.663465]  [<0002f3284c460940>] kernel_clone+0xd0/0x4b0
[    0.663467]  [<0002f3284c46115e>] kernel_thread+0xbe/0xe0
[    0.663469]  [<0002f3284c4e440e>] kthreadd+0x50e/0x7f0
[    0.663472]  [<0002f3284c38c04a>] __ret_from_fork+0x8a/0xf0
[    0.663475]  [<0002f3284ed57ff2>] ret_from_fork+0xa/0x38

Instead of allocating single pages per-PTE, bulk-allocate the shadow
memory prior to applying kasan_populate_vmalloc_pte() callback on a page
range.

Link: https://lkml.kernel.org/r/c61d3560297c93ed044f0b1af085610353a06a58.1747316918.git.agordeev@linux.ibm.com
Fixes: 3c5c3cfb9e ("kasan: support backing vmalloc space with real shadow memory")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Suggested-by: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-20 22:49:40 -07:00
Zhang Yi
66f28ffb38 mm/truncate: fix out-of-bounds when doing a right-aligned split
When performing a right split on a folio, the split_at2 may point to a
not-present page if the offset + length equals the original folio size,
which will trigger the following error:

 BUG: unable to handle page fault for address: ffffea0006000008
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 143ffb9067 P4D 143ffb9067 PUD 143ffb8067 PMD 0
 Oops: Oops: 0000 [#1] SMP PTI
 CPU: 0 UID: 0 PID: 502640 Comm: fsx Not tainted 6.15.0-rc3-gc6156189fc6b #889 PR
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/4
 RIP: 0010:truncate_inode_partial_folio+0x208/0x620
 Code: ff 03 48 01 da e8 78 7e 13 00 48 83 05 10 b5 5a 0c 01 85 c0 0f 85 1c 02 001
 RSP: 0018:ffffc90005bafab0 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: ffffea0005ffff00 RCX: 0000000000000002
 RDX: 000000000000000c RSI: 0000000000013975 RDI: ffffc90005bafa30
 RBP: ffffea0006000000 R08: 0000000000000000 R09: 00000000000009bf
 R10: 00000000000007e0 R11: 0000000000000000 R12: 0000000000001633
 R13: 0000000000000000 R14: ffffea0005ffff00 R15: fffffffffffffffe
 FS:  00007f9f9a161740(0000) GS:ffff8894971fd000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: ffffea0006000008 CR3: 000000017c2ae000 CR4: 00000000000006f0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
  <TASK>
  truncate_inode_pages_range+0x226/0x720
  truncate_pagecache+0x57/0x90
  ...

Fix this issue by skipping the split if truncation aligns with the folio
size, make sure the split page number lies within the folio.

Link: https://lkml.kernel.org/r/20250512062825.3533342-1-yi.zhang@huaweicloud.com
Fixes: 7460b470a1 ("mm/truncate: use folio_split() in truncate operation")
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: ErKun Yang <yangerkun@huawei.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-20 22:49:39 -07:00
Tianyang Zhang
e05741fb10 mm/page_alloc.c: avoid infinite retries caused by cpuset race
__alloc_pages_slowpath has no change detection for ac->nodemask in the
part of retry path, while cpuset can modify it in parallel.  For some
processes that set mempolicy as MPOL_BIND, this results ac->nodemask
changes, and then the should_reclaim_retry will judge based on the latest
nodemask and jump to retry, while the get_page_from_freelist only
traverses the zonelist from ac->preferred_zoneref, which selected by a
expired nodemask and may cause infinite retries in some cases

cpu 64:
__alloc_pages_slowpath {
        /* ..... */
retry:
        /* ac->nodemask = 0x1, ac->preferred->zone->nid = 1 */
        if (alloc_flags & ALLOC_KSWAPD)
                wake_all_kswapds(order, gfp_mask, ac);
        /* cpu 1:
        cpuset_write_resmask
            update_nodemask
                update_nodemasks_hier
                    update_tasks_nodemask
                        mpol_rebind_task
                         mpol_rebind_policy
                          mpol_rebind_nodemask
		// mempolicy->nodes has been modified,
		// which ac->nodemask point to

        */
        /* ac->nodemask = 0x3, ac->preferred->zone->nid = 1 */
        if (should_reclaim_retry(gfp_mask, order, ac, alloc_flags,
                                 did_some_progress > 0, &no_progress_loops))
                goto retry;
}

Simultaneously starting multiple cpuset01 from LTP can quickly reproduce
this issue on a multi node server when the maximum memory pressure is
reached and the swap is enabled

Link: https://lkml.kernel.org/r/20250416082405.20988-1-zhangtianyang@loongson.cn
Fixes: c33d6c06f6 ("mm, page_alloc: avoid looking up the first zone in a zonelist twice")
Signed-off-by: Tianyang Zhang <zhangtianyang@loongson.cn>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-20 22:49:37 -07:00
Keith Busch
1c9a93bf1d dmapool: add NUMA affinity support
Introduce dma_pool_create_node(), like dma_pool_create() but taking an
additional NUMA node argument. Allocate struct dma_pool on the desired
node, and store the node on dma_pool for allocating struct dma_page.
Make dma_pool_create() an alias for dma_pool_create_node() with node set
to NUMA_NO_NODE.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2025-05-20 05:34:27 +02:00
Linus Torvalds
e72e784fb1 Merge tag 'mm-hotfixes-stable-2025-05-17-09-41' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull hotfixes from Andrew Morton:
 "Nine singleton hotfixes, all MM.  Four are cc:stable"

* tag 'mm-hotfixes-stable-2025-05-17-09-41' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  mm: userfaultfd: correct dirty flags set for both present and swap pte
  zsmalloc: don't underflow size calculation in zs_obj_write()
  mm/page_alloc: fix race condition in unaccepted memory handling
  mm/page_alloc: ensure try_alloc_pages() plays well with unaccepted memory
  MAINTAINERS: add mm GUP section
  mm/codetag: move tag retrieval back upfront in __free_pages()
  mm/memory: fix mapcount / refcount sanity check for mTHP reuse
  kernel/fork: only call untrack_pfn_clear() on VMAs duplicated for fork()
  mm: hugetlb: fix incorrect fallback for subpool
2025-05-17 10:56:52 -07:00
Jakub Kicinski
bebd7b2626 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-6.15-rc7).

Conflicts:

tools/testing/selftests/drivers/net/hw/ncdevmem.c
  97c4e094a4 ("tests/ncdevmem: Fix double-free of queue array")
  2f1a805f32 ("selftests: ncdevmem: Implement devmem TCP TX")
https://lore.kernel.org/20250514122900.1e77d62d@canb.auug.org.au

Adjacent changes:

net/core/devmem.c
net/core/devmem.h
  0afc44d8cd ("net: devmem: fix kernel panic when netlink socket close after module unload")
  bd61848900 ("net: devmem: Implement TX path")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-15 11:28:30 -07:00
Linus Torvalds
e238e49b18 Merge tag 'vfs-6.15-rc7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:

 - Ensure that simple_xattr_list() always includes security.* xattrs

 - Fix eventpoll busy loop optimization when combined with timeouts

 - Disable swapon() for devices with block sizes greater than page sizes

 - Don't call errseq_set() twice during mark_buffer_write_io_error().
   Just use mapping_set_error() which takes care to not deference
   unconditionally

* tag 'vfs-6.15-rc7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  fs: Remove redundant errseq_set call in mark_buffer_write_io_error.
  swapfile: disable swapon for bs > ps devices
  fs/eventpoll: fix endless busy loop after timeout has expired
  fs/xattr.c: fix simple_xattr_list to always include security.* xattrs
2025-05-12 10:04:14 -07:00
Barry Song
75cb1cca2c mm: userfaultfd: correct dirty flags set for both present and swap pte
As David pointed out, what truly matters for mremap and userfaultfd move
operations is the soft dirty bit.  The current comment and
implementation—which always sets the dirty bit for present PTEs and
fails to set the soft dirty bit for swap PTEs—are incorrect.  This could
break features like Checkpoint-Restore in Userspace (CRIU).

This patch updates the behavior to correctly set the soft dirty bit for
both present and swap PTEs in accordance with mremap.

Link: https://lkml.kernel.org/r/20250508220912.7275-1-21cnbao@gmail.com
Fixes: adef440691 ("userfaultfd: UFFDIO_MOVE uABI")
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Reported-by: David Hildenbrand <david@redhat.com>
Closes: https://lore.kernel.org/linux-mm/02f14ee1-923f-47e3-a994-4950afb9afcc@redhat.com/
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11 17:29:55 -07:00
Sergey Senozhatsky
02f5bf89f0 zsmalloc: don't underflow size calculation in zs_obj_write()
Do not mix class->size and object size during offsets/sizes calculation in
zs_obj_write().  Size classes can merge into clusters, based on
objects-per-zspage and pages-per-zspage characteristics, so some size
classes can store objects smaller than class->size.  This becomes
problematic when object size is much smaller than class->size.  zsmalloc
can falsely decide that object spans two physical pages, because a larger
class->size value is used for that check, while the actual object is much
smaller and fits the free space of the first physical page, so there is
nothing to write to the second page and memcpy() size calculation
underflows.

 Unable to handle kernel paging request at virtual address ffffc00081ff4000
 pc : __memcpy+0x10/0x24
 lr : zs_obj_write+0x1b0/0x1d0 [zsmalloc]
 Call trace:
  __memcpy+0x10/0x24 (P)
  zram_write_page+0x150/0x4fc [zram]
  zram_submit_bio+0x5e0/0x6a4 [zram]
  __submit_bio+0x168/0x220
  submit_bio_noacct_nocheck+0x128/0x2c8
  submit_bio_noacct+0x19c/0x2f8

This is mostly seen on system with larger page-sizes, because size class
cluters of such systems hold wider size ranges than on 4K PAGE_SIZE
systems.

Assume a 16K PAGE_SIZE system, a write of 820 bytes object to a 864-bytes
size class at offset 15560.  15560 + 864 is more than 16384 so zsmalloc
attempts to memcpy() it to two physical pages.  However, 16384 - 15560 =
824 which is more than 820, so the object in fact doesn't span two
physical pages, and there is no data to write to the second physical page.

We always know the exact size in bytes of the object that we are about to
write (store), so use it instead of class->size.

Link: https://lkml.kernel.org/r/20250507054312.4135983-1-senozhatsky@chromium.org
Fixes: 44f7641349 ("zsmalloc: introduce new object mapping API")
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reported-by: Igor Belousov <igor.b@beldev.am>
Tested-by: Igor Belousov <igor.b@beldev.am>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11 17:26:07 -07:00
Kirill A. Shutemov
fefc075182 mm/page_alloc: fix race condition in unaccepted memory handling
The page allocator tracks the number of zones that have unaccepted memory
using static_branch_enc/dec() and uses that static branch in hot paths to
determine if it needs to deal with unaccepted memory.

Borislav and Thomas pointed out that the tracking is racy: operations on
static_branch are not serialized against adding/removing unaccepted pages
to/from the zone.

Sanity checks inside static_branch machinery detects it:

WARNING: CPU: 0 PID: 10 at kernel/jump_label.c:276 __static_key_slow_dec_cpuslocked+0x8e/0xa0

The comment around the WARN() explains the problem:

	/*
	 * Warn about the '-1' case though; since that means a
	 * decrement is concurrent with a first (0->1) increment. IOW
	 * people are trying to disable something that wasn't yet fully
	 * enabled. This suggests an ordering problem on the user side.
	 */

The effect of this static_branch optimization is only visible on
microbenchmark.

Instead of adding more complexity around it, remove it altogether.

Link: https://lkml.kernel.org/r/20250506133207.1009676-1-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Fixes: dcdfdd40fa ("mm: Add support for unaccepted memory")
Link: https://lore.kernel.org/all/20250506092445.GBaBnVXXyvnazly6iF@fat_crate.local
Reported-by: Borislav Petkov <bp@alien8.de>
Tested-by: Borislav Petkov (AMD) <bp@alien8.de>
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org>	[6.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11 17:26:07 -07:00
Kirill A. Shutemov
23fa022a07 mm/page_alloc: ensure try_alloc_pages() plays well with unaccepted memory
try_alloc_pages() will not attempt to allocate memory if the system has
*any* unaccepted memory.  Memory is accepted as needed and can remain in
the system indefinitely, causing the interface to always fail.

Rather than immediately giving up, attempt to use already accepted memory
on free lists.

Pass 'alloc_flags' to cond_accept_memory() and do not accept new memory
for ALLOC_TRYLOCK requests.

Found via code inspection - only BPF uses this at present and the
runtime effects are unclear.

Link: https://lkml.kernel.org/r/20250506112509.905147-2-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Fixes: 97769a53f1 ("mm, bpf: Introduce try_alloc_pages() for opportunistic page allocation")
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11 17:26:07 -07:00
David Wang
0ae0227fa3 mm/codetag: move tag retrieval back upfront in __free_pages()
Commit 51ff4d7486 ("mm: avoid extra mem_alloc_profiling_enabled()
 checks") introduces a possible use-after-free scenario, when page
is non-compound, page[0] could be released by other thread right
after put_page_testzero failed in current thread, pgalloc_tag_sub_pages
afterwards would manipulate an invalid page for accounting remaining
pages:

[timeline]   [thread1]                     [thread2]
  |          alloc_page non-compound
  V
  |                                        get_page, rf counter inc
  V
  |          in ___free_pages
  |          put_page_testzero fails
  V
  |                                        put_page, page released
  V
  |          in ___free_pages,
  |          pgalloc_tag_sub_pages
  |          manipulate an invalid page
  V

Restore __free_pages() to its state before, retrieve alloc tag
beforehand.

Link: https://lkml.kernel.org/r/20250505193034.91682-1-00107082@163.com
Fixes: 51ff4d7486 ("mm: avoid extra mem_alloc_profiling_enabled() checks")
Signed-off-by: David Wang <00107082@163.com>
Acked-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11 17:26:06 -07:00
Kairui Song
4b7c0857f8 mm/memory: fix mapcount / refcount sanity check for mTHP reuse
The following WARNING was triggered during swap stress test with mTHP
enabled:

[ 6609.335758] ------------[ cut here ]------------
[ 6609.337758] WARNING: CPU: 82 PID: 755116 at mm/memory.c:3794 do_wp_page+0x1084/0x10e0
[ 6609.340922] Modules linked in: zram virtiofs
[ 6609.342699] CPU: 82 UID: 0 PID: 755116 Comm: sh Kdump: loaded Not tainted 6.15.0-rc1+ #1429 PREEMPT(voluntary)
[ 6609.347620] Hardware name: Red Hat KVM/RHEL-AV, BIOS 0.0.0 02/06/2015
[ 6609.349909] RIP: 0010:do_wp_page+0x1084/0x10e0
[ 6609.351532] Code: ff ff 48 c7 c6 80 ba 49 82 4c 89 ef e8 95 fd fe ff 0f 0b bd f5 ff ff ff e9 43 fb ff ff 41 83 a9 bc 12 00 00 01 e9 5c fb ff ff <0f> 0b e9 a6 fc ff ff 65 ff 00 f0 48 0f b
a 6d 00 1f 0f 83 82 fc ff
[ 6609.357959] RSP: 0000:ffffc90002273d40 EFLAGS: 00010287
[ 6609.359915] RAX: 000000000000000f RBX: 0000000000000000 RCX: 000fffffffe00000
[ 6609.362606] RDX: 0000000000000010 RSI: 000055a119ac1000 RDI: ffffea000ae6ec00
[ 6609.365143] RBP: ffffea000ae6ec68 R08: 84000002b9bb1025 R09: 000055a119ab6000
[ 6609.367569] R10: ffff8881caa2ad80 R11: 0000000000000000 R12: ffff8881caa2ad80
[ 6609.370255] R13: ffffea000ae6ec00 R14: 000055a119ac1c9c R15: ffffc90002273dd8
[ 6609.373007] FS:  00007f08e467f740(0000) GS:ffff88a07c214000(0000) knlGS:0000000000000000
[ 6609.375999] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 6609.377946] CR2: 000055a119ac1c9c CR3: 00000001adfd6005 CR4: 0000000000770eb0
[ 6609.380376] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 6609.382853] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 6609.385216] PKRU: 55555554
[ 6609.386141] Call Trace:
[ 6609.387017]  <TASK>
[ 6609.387718]  ? ___pte_offset_map+0x1b/0x110
[ 6609.389056]  __handle_mm_fault+0xa51/0xf00
[ 6609.390363]  ? exc_page_fault+0x6a/0x140
[ 6609.391629]  handle_mm_fault+0x13d/0x360
[ 6609.392856]  do_user_addr_fault+0x2f2/0x7f0
[ 6609.394160]  ? sigprocmask+0x77/0xa0
[ 6609.395375]  exc_page_fault+0x6a/0x140
[ 6609.396735]  asm_exc_page_fault+0x26/0x30
[ 6609.398224] RIP: 0033:0x55a1050bc18b
[ 6609.399567] Code: 8b 3f 4d 85 ff 74 40 41 39 5f 18 75 f2 49 8b 7f 08 44 38 27 75 e9 4c 89 c6 4c 89 45 c8 e8 bd 83 fa ff 4c 8b 45 c8 85 c0 75 d5 <41> 83 47 1c 01 48 83 c4 28 4c 89 f8 5b 4
1 5c 41 5d 41 5e 41 5f 5d
[ 6609.405971] RSP: 002b:00007ffcf5f37d90 EFLAGS: 00010246
[ 6609.407737] RAX: 0000000000000000 RBX: 00000000182768fa RCX: 0000000000000000
[ 6609.410151] RDX: 00000000000000fa RSI: 000055a105175c7b RDI: 000055a119ac1c60
[ 6609.412606] RBP: 00007ffcf5f37de0 R08: 000055a105175c7b R09: 0000000000000000
[ 6609.414998] R10: 000000004d2dfb5a R11: 0000000000000246 R12: 0000000000000050
[ 6609.417193] R13: 00000000000000fa R14: 000055a119abaf60 R15: 000055a119ac1c80
[ 6609.419268]  </TASK>
[ 6609.419928] ---[ end trace 0000000000000000 ]---

The WARN_ON here is simply incorrect.  The refcount here must be at least
the mapcount, not the opposite.  Each mapcount must have a corresponding
refcount, but the refcount may increase if other components grab the
folio, which is acceptable.  Meanwhile, having a mapcount larger than
refcount is a real problem.

So fix the WARN_ON condition.

Link: https://lkml.kernel.org/r/20250425074325.61833-1-ryncsn@gmail.com
Fixes: 1da190f4d0 ("mm: Copy-on-Write (COW) reuse support for PTE-mapped THP")
Signed-off-by: Kairui Song <kasong@tencent.com>
Reported-by: Kairui Song <kasong@tencent.com>
Closes: https://lore.kernel.org/all/CAMgjq7D+ea3eg9gRCVvRnto3Sv3_H3WVhupX4e=k8T5QAfBHbw@mail.gmail.com/
Suggested-by: David Hildenbrand <david@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11 17:26:06 -07:00
Wupeng Ma
a833a693a4 mm: hugetlb: fix incorrect fallback for subpool
During our testing with hugetlb subpool enabled, we observe that
hstate->resv_huge_pages may underflow into negative values.  Root cause
analysis reveals a race condition in subpool reservation fallback handling
as follow:

hugetlb_reserve_pages()
    /* Attempt subpool reservation */
    gbl_reserve = hugepage_subpool_get_pages(spool, chg);

    /* Global reservation may fail after subpool allocation */
    if (hugetlb_acct_memory(h, gbl_reserve) < 0)
        goto out_put_pages;

out_put_pages:
    /* This incorrectly restores reservation to subpool */
    hugepage_subpool_put_pages(spool, chg);

When hugetlb_acct_memory() fails after subpool allocation, the current
implementation over-commits subpool reservations by returning the full
'chg' value instead of the actual allocated 'gbl_reserve' amount.  This
discrepancy propagates to global reservations during subsequent releases,
eventually causing resv_huge_pages underflow.

This problem can be trigger easily with the following steps:
1. reverse hugepage for hugeltb allocation
2. mount hugetlbfs with min_size to enable hugetlb subpool
3. alloc hugepages with two task(make sure the second will fail due to
   insufficient amount of hugepages)
4. with for a few seconds and repeat step 3 which will make
   hstate->resv_huge_pages to go below zero.

To fix this problem, return corrent amount of pages to subpool during the
fallback after hugepage_subpool_get_pages is called.

Link: https://lkml.kernel.org/r/20250410062633.3102457-1-mawupeng1@huawei.com
Fixes: 1c5ecae3a9 ("hugetlbfs: add minimum size accounting to subpools")
Signed-off-by: Wupeng Ma <mawupeng1@huawei.com>
Tested-by: Joshua Hahn <joshua.hahnjy@gmail.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Ma Wupeng <mawupeng1@huawei.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11 17:26:06 -07:00
Linus Torvalds
6f5bf947ba Merge tag 'its-for-linus-20250509' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 ITS mitigation from Dave Hansen:
 "Mitigate Indirect Target Selection (ITS) issue.

  I'd describe this one as a good old CPU bug where the behavior is
  _obviously_ wrong, but since it just results in bad predictions it
  wasn't wrong enough to notice. Well, the researchers noticed and also
  realized that thus bug undermined a bunch of existing indirect branch
  mitigations.

  Thus the unusually wide impact on this one. Details:

  ITS is a bug in some Intel CPUs that affects indirect branches
  including RETs in the first half of a cacheline. Due to ITS such
  branches may get wrongly predicted to a target of (direct or indirect)
  branch that is located in the second half of a cacheline. Researchers
  at VUSec found this behavior and reported to Intel.

  Affected processors:

   - Cascade Lake, Cooper Lake, Whiskey Lake V, Coffee Lake R, Comet
     Lake, Ice Lake, Tiger Lake and Rocket Lake.

  Scope of impact:

   - Guest/host isolation:

     When eIBRS is used for guest/host isolation, the indirect branches
     in the VMM may still be predicted with targets corresponding to
     direct branches in the guest.

   - Intra-mode using cBPF:

     cBPF can be used to poison the branch history to exploit ITS.
     Realigning the indirect branches and RETs mitigates this attack
     vector.

   - User/kernel:

     With eIBRS enabled user/kernel isolation is *not* impacted by ITS.

   - Indirect Branch Prediction Barrier (IBPB):

     Due to this bug indirect branches may be predicted with targets
     corresponding to direct branches which were executed prior to IBPB.
     This will be fixed in the microcode.

  Mitigation:

  As indirect branches in the first half of cacheline are affected, the
  mitigation is to replace those indirect branches with a call to thunk that
  is aligned to the second half of the cacheline.

  RETs that take prediction from RSB are not affected, but they may be
  affected by RSB-underflow condition. So, RETs in the first half of
  cacheline are also patched to a return thunk that executes the RET aligned
  to second half of cacheline"

* tag 'its-for-linus-20250509' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  selftest/x86/bugs: Add selftests for ITS
  x86/its: FineIBT-paranoid vs ITS
  x86/its: Use dynamic thunks for indirect branches
  x86/ibt: Keep IBT disabled during alternative patching
  mm/execmem: Unify early execmem_cache behaviour
  x86/its: Align RETs in BHB clear sequence to avoid thunking
  x86/its: Add support for RSB stuffing mitigation
  x86/its: Add "vmexit" option to skip mitigation on some CPUs
  x86/its: Enable Indirect Target Selection mitigation
  x86/its: Add support for ITS-safe return thunk
  x86/its: Add support for ITS-safe indirect thunk
  x86/its: Enumerate Indirect Target Selection (ITS) bug
  Documentation: x86/bugs/its: Add ITS documentation
2025-05-11 17:23:03 -07:00
Linus Torvalds
f717acc6e9 Merge tag 'fixes-2025-05-11' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock
Pull memblock fixes from Mike Rapoport:

 - Mark set_high_memory() as __init to fix section mismatch

 - Accept memory allocated in memblock_double_array() to mitigate crash
   of SNP guests

* tag 'fixes-2025-05-11' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock:
  memblock: Accept allocated memory before use in memblock_double_array()
  mm,mm_init: Mark set_high_memory as __init
2025-05-11 10:23:53 -07:00
Peter Zijlstra
d6d1e3e658 mm/execmem: Unify early execmem_cache behaviour
Early kernel memory is RWX, only at the end of early boot (before SMP)
do we mark things ROX. Have execmem_cache mirror this behaviour for
early users.

This avoids having to remember what code is execmem and what is not --
we can poke everything with impunity ;-) Also performance for not
having to do endless text_poke_mm switches.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
2025-05-09 13:33:20 -07:00
Ryan Roberts
44562c71e2 mm/vmalloc: Enter lazy mmu mode while manipulating vmalloc ptes
Wrap vmalloc's pte table manipulation loops with
arch_enter_lazy_mmu_mode() / arch_leave_lazy_mmu_mode(). This provides
the arch code with the opportunity to optimize the pte manipulations.

Note that vmap_pfn() already uses lazy mmu mode since it delegates to
apply_to_page_range() which enters lazy mmu mode for both user and
kernel mappings.

These hooks will shortly be used by arm64 to improve vmalloc
performance.

Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Tested-by: Luiz Capitulino <luizcap@redhat.com>
Link: https://lore.kernel.org/r/20250422081822.1836315-11-ryan.roberts@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2025-05-09 13:43:07 +01:00
Ryan Roberts
2fba13371f mm/vmalloc: Gracefully unmap huge ptes
Commit f7ee1f13d6 ("mm/vmalloc: enable mapping of huge pages at pte
level in vmap") added its support by reusing the set_huge_pte_at() API,
which is otherwise only used for user mappings. But when unmapping those
huge ptes, it continued to call ptep_get_and_clear(), which is a
layering violation. To date, the only arch to implement this support is
powerpc and it all happens to work ok for it.

But arm64's implementation of ptep_get_and_clear() can not be safely
used to clear a previous set_huge_pte_at(). So let's introduce a new
arch opt-in function, arch_vmap_pte_range_unmap_size(), which can
provide the size of a (present) pte. Then we can call
huge_ptep_get_and_clear() to tear it down properly.

Note that if vunmap_range() is called with a range that starts in the
middle of a huge pte-mapped page, we must unmap the entire huge page so
the behaviour is consistent with pmd and pud block mappings. In this
case emit a warning just like we do for pmd/pud mappings.

Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Tested-by: Luiz Capitulino <luizcap@redhat.com>
Link: https://lore.kernel.org/r/20250422081822.1836315-9-ryan.roberts@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2025-05-09 13:43:07 +01:00
Ryan Roberts
61ef8ddaa3 mm/vmalloc: Warn on improper use of vunmap_range()
A call to vmalloc_huge() may cause memory blocks to be mapped at pmd or
pud level. But it is possible to subsequently call vunmap_range() on a
sub-range of the mapped memory, which partially overlaps a pmd or pud.
In this case, vmalloc unmaps the entire pmd or pud so that the
no-overlapping portion is also unmapped. Clearly that would have a bad
outcome, but it's not something that any callers do today as far as I
can tell. So I guess it's just expected that callers will not do this.

However, it would be useful to know if this happened in future; let's
add a warning to cover the eventuality.

Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Tested-by: Luiz Capitulino <luizcap@redhat.com>
Link: https://lore.kernel.org/r/20250422081822.1836315-8-ryan.roberts@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2025-05-09 13:43:07 +01:00
Ryan Roberts
91e40668e7 mm/page_table_check: Batch-check pmds/puds just like ptes
Convert page_table_check_p[mu]d_set(...) to
page_table_check_p[mu]ds_set(..., nr) to allow checking a contiguous set
of pmds/puds in single batch. We retain page_table_check_p[mu]d_set(...)
as macros that call new batch functions with nr=1 for compatibility.

arm64 is about to reorganise its pte/pmd/pud helpers to reuse more code
and to allow the implementation for huge_pte to more efficiently set
ptes/pmds/puds in batches. We need these batch-helpers to make the
refactoring possible.

Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Tested-by: Luiz Capitulino <luizcap@redhat.com>
Link: https://lore.kernel.org/r/20250422081822.1836315-4-ryan.roberts@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2025-05-09 13:43:07 +01:00
Tom Lendacky
da8bf5daa5 memblock: Accept allocated memory before use in memblock_double_array()
When increasing the array size in memblock_double_array() and the slab
is not yet available, a call to memblock_find_in_range() is used to
reserve/allocate memory. However, the range returned may not have been
accepted, which can result in a crash when booting an SNP guest:

  RIP: 0010:memcpy_orig+0x68/0x130
  Code: ...
  RSP: 0000:ffffffff9cc03ce8 EFLAGS: 00010006
  RAX: ff11001ff83e5000 RBX: 0000000000000000 RCX: fffffffffffff000
  RDX: 0000000000000bc0 RSI: ffffffff9dba8860 RDI: ff11001ff83e5c00
  RBP: 0000000000002000 R08: 0000000000000000 R09: 0000000000002000
  R10: 000000207fffe000 R11: 0000040000000000 R12: ffffffff9d06ef78
  R13: ff11001ff83e5000 R14: ffffffff9dba7c60 R15: 0000000000000c00
  memblock_double_array+0xff/0x310
  memblock_add_range+0x1fb/0x2f0
  memblock_reserve+0x4f/0xa0
  memblock_alloc_range_nid+0xac/0x130
  memblock_alloc_internal+0x53/0xc0
  memblock_alloc_try_nid+0x3d/0xa0
  swiotlb_init_remap+0x149/0x2f0
  mem_init+0xb/0xb0
  mm_core_init+0x8f/0x350
  start_kernel+0x17e/0x5d0
  x86_64_start_reservations+0x14/0x30
  x86_64_start_kernel+0x92/0xa0
  secondary_startup_64_no_verify+0x194/0x19b

Mitigate this by calling accept_memory() on the memory range returned
before the slab is available.

Prior to v6.12, the accept_memory() interface used a 'start' and 'end'
parameter instead of 'start' and 'size', therefore the accept_memory()
call must be adjusted to specify 'start + size' for 'end' when applying
to kernels prior to v6.12.

Cc: stable@vger.kernel.org # see patch description, needs adjustments for <= 6.11
Fixes: dcdfdd40fa ("mm: Add support for unaccepted memory")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/da1ac73bf4ded761e21b4e4bb5178382a580cd73.1746725050.git.thomas.lendacky@amd.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
2025-05-09 08:53:12 +03:00
Kees Cook
5e88c48cb4 kbuild: Switch from -Wvla to -Wvla-larger-than=1
Variable Length Arrays (VLAs) on the stack must not be used in the kernel.
Function parameter VLAs[1] should be usable, but -Wvla will warn for
those. For example, this will produce a warning but it is not using a
stack VLA:

    int something(size_t n, int array[n]) { ...

Clang has no way yet to distinguish between the VLA types[2], so
depend on GCC for now to keep stack VLAs out of the tree by using GCC's
-Wvla-larger-than=N option (though GCC may split -Wvla similarly[3] to
how Clang is planning to).

While GCC 8+ supports -Wvla-larger-than, only 9+ supports ...=0[4],
so use -Wvla-larger-than=1. Adjust mm/kasan/Makefile to remove it from
CFLAGS (GCC <9 appears unable to disable the warning correctly[5]).

The VLA usage in lib/test_ubsan.c was removed in commit 9d7ca61b13
("lib/test_ubsan.c: VLA no longer used in kernel") so the lib/Makefile
disabling of VLA checking can be entirely removed.

Link: https://en.cppreference.com/w/c/language/array [1]
Link: https://github.com/llvm/llvm-project/issues/57098 [2]
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98217 [3]
Link: https://lore.kernel.org/lkml/7780883c-0ac8-4aaa-b850-469e33b50672@linux.ibm.com/ [4]
Link: https://lore.kernel.org/r/202505071331.4iOzqmuE-lkp@intel.com/ [5]
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Link: https://lore.kernel.org/r/20250418213235.work.532-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
2025-05-08 09:42:06 -07:00
Jakub Kicinski
6b02fd7799 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-6.15-rc6).

No conflicts.

Adjacent changes:

net/core/dev.c:
  08e9f2d584 ("net: Lock netdevices during dev_shutdown")
  a82dc19db1 ("net: avoid potential race between netdev_get_by_index_lock() and netns switch")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-08 08:59:02 -07:00
Petr Vaněk
7b08b74f3d mm: fix folio_pte_batch() on XEN PV
On XEN PV, folio_pte_batch() can incorrectly batch beyond the end of a
folio due to a corner case in pte_advance_pfn().  Specifically, when the
PFN following the folio maps to an invalidated MFN,

	expected_pte = pte_advance_pfn(expected_pte, nr);

produces a pte_none().  If the actual next PTE in memory is also
pte_none(), the pte_same() succeeds,

	if (!pte_same(pte, expected_pte))
		break;

the loop is not broken, and batching continues into unrelated memory.

For example, with a 4-page folio, the PTE layout might look like this:

[   53.465673] [ T2552] folio_pte_batch: printing PTE values at addr=0x7f1ac9dc5000
[   53.465674] [ T2552]   PTE[453] = 000000010085c125
[   53.465679] [ T2552]   PTE[454] = 000000010085d125
[   53.465682] [ T2552]   PTE[455] = 000000010085e125
[   53.465684] [ T2552]   PTE[456] = 000000010085f125
[   53.465686] [ T2552]   PTE[457] = 0000000000000000 <-- not present
[   53.465689] [ T2552]   PTE[458] = 0000000101da7125

pte_advance_pfn(PTE[456]) returns a pte_none() due to invalid PFN->MFN
mapping.  The next actual PTE (PTE[457]) is also pte_none(), so the loop
continues and includes PTE[457] in the batch, resulting in 5 batched
entries for a 4-page folio.  This triggers the following warning:

[   53.465751] [ T2552] page: refcount:85 mapcount:20 mapping:ffff88813ff4f6a8 index:0x110 pfn:0x10085c
[   53.465754] [ T2552] head: order:2 mapcount:80 entire_mapcount:0 nr_pages_mapped:4 pincount:0
[   53.465756] [ T2552] memcg:ffff888003573000
[   53.465758] [ T2552] aops:0xffffffff8226fd20 ino:82467c dentry name(?):"libc.so.6"
[   53.465761] [ T2552] flags: 0x2000000000416c(referenced|uptodate|lru|active|private|head|node=0|zone=2)
[   53.465764] [ T2552] raw: 002000000000416c ffffea0004021f08 ffffea0004021908 ffff88813ff4f6a8
[   53.465767] [ T2552] raw: 0000000000000110 ffff888133d8bd40 0000005500000013 ffff888003573000
[   53.465768] [ T2552] head: 002000000000416c ffffea0004021f08 ffffea0004021908 ffff88813ff4f6a8
[   53.465770] [ T2552] head: 0000000000000110 ffff888133d8bd40 0000005500000013 ffff888003573000
[   53.465772] [ T2552] head: 0020000000000202 ffffea0004021701 000000040000004f 00000000ffffffff
[   53.465774] [ T2552] head: 0000000300000003 8000000300000002 0000000000000013 0000000000000004
[   53.465775] [ T2552] page dumped because: VM_WARN_ON_FOLIO((_Generic((page + nr_pages - 1), const struct page *: (const struct folio *)_compound_head(page + nr_pages - 1), struct page *: (struct folio *)_compound_head(page + nr_pages - 1))) != folio)

Original code works as expected everywhere, except on XEN PV, where
pte_advance_pfn() can yield a pte_none() after balloon inflation due to
MFNs invalidation.  In XEN, pte_advance_pfn() ends up calling
__pte()->xen_make_pte()->pte_pfn_to_mfn(), which returns pte_none() when
mfn == INVALID_P2M_ENTRY.

The pte_pfn_to_mfn() documents that nastiness:

	If there's no mfn for the pfn, then just create an
	empty non-present pte.  Unfortunately this loses
	information about the original pfn, so
	pte_mfn_to_pfn is asymmetric.

While such hacks should certainly be removed, we can do better in
folio_pte_batch() and simply check ahead of time how many PTEs we can
possibly batch in our folio.

This way, we can not only fix the issue but cleanup the code: removing the
pte_pfn() check inside the loop body and avoiding end_ptr comparison +
arithmetic.

Link: https://lkml.kernel.org/r/20250502215019.822-2-arkamar@atlas.cz
Fixes: f8d937761d ("mm/memory: optimize fork() with PTE-mapped THP")
Co-developed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Petr Vaněk <arkamar@atlas.cz>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-07 23:39:42 -07:00
Frank van der Linden
dac2a4f663 mm/hugetlb: copy the CMA flag when demoting
Since commit d2d7867140 ("mm/hugetlb: enable bootmem allocation from CMA
areas"), a flag is used to mark hugetlb folios as allocated from CMA. 
This flag is also used to decide if it should be freed to CMA.

However, the flag isn't copied to the smaller folios when a hugetlb folio
is broken up for demotion, which would cause it to be freed incorrectly.

Fix this by copying the flag to the smaller order hugetlb pages created
from the original one.

Link: https://lkml.kernel.org/r/20250501044325.20365-1-fvdl@google.com
Fixes: d2d7867140 ("mm/hugetlb: enable bootmem allocation from CMA areas")
Signed-off-by: Frank van der Linden <fvdl@google.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Jane Chu <Jane.Chu@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-07 23:39:42 -07:00
Kairui Song
9a9794a81a mm, swap: fix false warning for large allocation with !THP_SWAP
The !CONFIG_THP_SWAP check existed before just fine because slot cache
would reject high order allocation and let the caller split all folios and
try again.

But slot cache is gone, so large allocation will directly go to the
allocator, and the allocator should just fail silently to inform caller to
do the folio split, this is totally fine and expected.

Remove this meaningless warning.

Link: https://lkml.kernel.org/r/20250429094803.85518-1-ryncsn@gmail.com
Fixes: 0ff67f990b ("mm, swap: remove swap slot cache")
Signed-off-by: Kairui Song <kasong@tencent.com>
Reported-by: Heiko Carstens <hca@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/20250428135252.25453B17-hca@linux.ibm.com/
Tested-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-07 23:39:41 -07:00
Kees Cook
a0309faf1c mm: vmalloc: support more granular vrealloc() sizing
Introduce struct vm_struct::requested_size so that the requested
(re)allocation size is retained separately from the allocated area size. 
This means that KASAN will correctly poison the correct spans of requested
bytes.  This also means we can support growing the usable portion of an
allocation that can already be supported by the existing area's existing
allocation.

Link: https://lkml.kernel.org/r/20250426001105.it.679-kees@kernel.org
Fixes: 3ddc2fefe6 ("mm: vmalloc: implement vrealloc()")
Signed-off-by: Kees Cook <kees@kernel.org>
Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Closes: https://lore.kernel.org/all/20250408192503.6149a816@outsider.home/
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-07 23:39:41 -07:00
Gavin Guo
be6e843fc5 mm/huge_memory: fix dereferencing invalid pmd migration entry
When migrating a THP, concurrent access to the PMD migration entry during
a deferred split scan can lead to an invalid address access, as
illustrated below.  To prevent this invalid access, it is necessary to
check the PMD migration entry and return early.  In this context, there is
no need to use pmd_to_swp_entry and pfn_swap_entry_to_page to verify the
equality of the target folio.  Since the PMD migration entry is locked, it
cannot be served as the target.

Mailing list discussion and explanation from Hugh Dickins: "An anon_vma
lookup points to a location which may contain the folio of interest, but
might instead contain another folio: and weeding out those other folios is
precisely what the "folio != pmd_folio((*pmd)" check (and the "risk of
replacing the wrong folio" comment a few lines above it) is for."

BUG: unable to handle page fault for address: ffffea60001db008
CPU: 0 UID: 0 PID: 2199114 Comm: tee Not tainted 6.14.0+ #4 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:split_huge_pmd_locked+0x3b5/0x2b60
Call Trace:
<TASK>
try_to_migrate_one+0x28c/0x3730
rmap_walk_anon+0x4f6/0x770
unmap_folio+0x196/0x1f0
split_huge_page_to_list_to_order+0x9f6/0x1560
deferred_split_scan+0xac5/0x12a0
shrinker_debugfs_scan_write+0x376/0x470
full_proxy_write+0x15c/0x220
vfs_write+0x2fc/0xcb0
ksys_write+0x146/0x250
do_syscall_64+0x6a/0x120
entry_SYSCALL_64_after_hwframe+0x76/0x7e

The bug is found by syzkaller on an internal kernel, then confirmed on
upstream.

Link: https://lkml.kernel.org/r/20250421113536.3682201-1-gavinguo@igalia.com
Link: https://lore.kernel.org/all/20250414072737.1698513-1-gavinguo@igalia.com/
Link: https://lore.kernel.org/all/20250418085802.2973519-1-gavinguo@igalia.com/
Fixes: 84c3fc4e9c ("mm: thp: check pmd migration entry in common path")
Signed-off-by: Gavin Guo <gavinguo@igalia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Cc: Florent Revest <revest@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-07 23:39:38 -07:00
Oscar Salvador
42e31f0daf mm,mm_init: Mark set_high_memory as __init
set_high_memory() touches arch_zone_lowest_possible_pfn which is
marked as __initdata, which creates a section mismatch.
Since the only user of the function is free_area_init() which is also marked
as __init, mark set_high_memory() as __init as well.

Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202505060901.Qcs06UoB-lkp@intel.com/
Link: https://lore.kernel.org/r/20250506111012.108743-1-osalvador@suse.de
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
2025-05-06 20:07:25 +03:00
Luis Chamberlain
6ba0982c32 swapfile: disable swapon for bs > ps devices
Devices which have a requirement for bs > ps cannot be supported for
swap as swap still needs work. Now that the block device cache sets the
min order for block devices we need this stop gap otherwise all
swap operations are rejected.

Without this you'll end up with errors on these devices as the swap
code still needs much love to support min order.

With this we at least now put a stop gap of its use, until the
swap subsystem completes its major overhaul:

mkswap: /dev/nvme3n1: warning: wiping old swap signature.
Setting up swapspace version 1, size = 100 GiB (107374178304 bytes)
no label, UUID=6af76b5c-7e7b-4902-b7f7-4c24dde6fa36
swapon: /dev/nvme3n1: swapon failed: Invalid argument

Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/aBkS926thy9zvdZb@bombadil.infradead.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-05-06 10:46:19 +02:00
Christoph Hellwig
194df9f66d mm: remove NR_BOUNCE zone stat
The stat is always 0 now, so remove it and hardwire the user visible
output to 0.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20250505081138.3435992-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-05 13:22:39 -06:00
Peter Zijlstra
55284f7013 mm: Add vmalloc_huge_node()
To enable node specific hash-tables using huge pages if possible.

[bigeasy: use __vmalloc_node_range_noprof(), add nommu bits, inline
vmalloc_huge]

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250416162921.513656-3-bigeasy@linutronix.de
2025-05-03 12:02:05 +02:00