Pull xmb client fixes from Steve French:

 - Noisy log message cleanup

 - Important netfs fix for cifs crash in generic/074

 - Three minor improvements to use of hashing (multichannel and mount
   improvements)

 - Fix decryption crash for large read with small esize

* tag '6.12rc-more-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb: client: make SHA-512 TFM ephemeral
  smb: client: make HMAC-MD5 TFM ephemeral
  smb: client: stop flooding dmesg in smb2_calc_signature()
  smb: client: allocate crypto only for primary server
  smb: client: fix UAF in async decryption
  netfs: Fix write oops in generic/346 (9p) and generic/074 (cifs)

Pull power management fix from Rafael Wysocki:
 "Fix idle states enumeration in the intel_idle driver on platforms
  supporting multiple flavors of the C6 idle state (Artem Bityutskiy)"

* tag 'pm-6.12-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  intel_idle: fix ACPI _CST matching for newer Xeon platforms

Pull UML updates from Richard Weinberger:

 - Removal of dead code (TT mode leftovers, etc)

 - Fixes for the network vector driver

 - Fixes for time-travel mode

* tag 'uml-for-linus-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux:
  um: fix time-travel syscall scheduling hack
  um: Remove outdated asm/sysrq.h header
  um: Remove the declaration of user_thread function
  um: Remove the call to SUBARCH_EXECVE1 macro
  um: Remove unused mm_fd field from mm_id
  um: Remove unused fields from thread_struct
  um: Remove the redundant newpage check in update_pte_range
  um: Remove unused kpte_clear_flush macro
  um: Remove obsoleted declaration for execute_syscall_skas
  user_mode_linux_howto_v2: add VDE vector support in doc
  vector_user: add VDE support
  um: remove ARCH_NO_PREEMPT_DYNAMIC
  um: vector: Fix NAPI budget handling
  um: vector: Replace locks guarding queue depth with atomics
  um: remove variable stack array in os_rcv_fd_msg()

ovl_open_realfile() is wrongly called twice after conversion to
new struct fd.

Fixes: 88a2f646 ("struct fd: representation change")
Reported-by: syzbot+d9efec94dcbfa0de1c07@syzkaller.appspotmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull more random number generator updates from Jason Donenfeld:

 - Christophe realized that the LoongArch64 instructions could be
   scheduled more similar to how GCC generates code, which Ruoyao
   implemented, for a 5% speedup from basically some rearrangements

 - An update to MAINTAINERS to match the right files

* tag 'random-6.12-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random:
  LoongArch: vDSO: Tune chacha implementation
  MAINTAINERS: make vDSO getrandom matches more generic

Pull bitmap updates from Yury Norov:

 - switch all bitmamp APIs from inline to __always_inline (Brian Norris)

   The __always_inline series improves on code generation, and now with
   the latest compiler versions is required to avoid compilation
   warnings. It spent enough in my backlog, and I'm thankful to Brian
   Norris for taking over and moving it forward.

 - introduce GENMASK_U128() macro (Anshuman Khandual)

   GENMASK_U128() is a prerequisite needed for arm64 development

* tag 'bitmap-for-6.12' of https://github.com/norov/linux:
  lib/test_bits.c: Add tests for GENMASK_U128()
  uapi: Define GENMASK_U128
  nodemask: Switch from inline to __always_inline
  cpumask: Switch from inline to __always_inline
  bitmap: Switch from inline to __always_inline
  find: Switch from inline to __always_inline

Pull tomoyo updates from Tetsuo Handa:
 "One bugfix patch, one preparation patch, and one conversion patch.

  TOMOYO is useful as an analysis tool for learning how a Linux system
  works. My boss was hoping that SELinux's policy is generated from what
  TOMOYO has observed. A translated paper describing it is available at

    https://master.dl.sourceforge.net/project/tomoyo/docs/nsf2003-en.pdf/nsf2003-en.pdf?viasf=1

  Although that attempt failed due to mapping problem between inode and
  pathname, TOMOYO remains as an access restriction tool due to ability
  to write custom policy by individuals.

  I was delivering pure LKM version of TOMOYO (named AKARI) to users who
  cannot afford rebuilding their distro kernels with TOMOYO enabled. But
  since the LSM framework was converted to static calls, it became more
  difficult to deliver AKARI to such users. Therefore, I decided to
  update TOMOYO so that people can use mostly LKM version of TOMOYO with
  minimal burden for both distributors and users"

* tag 'tomoyo-pr-20240927' of git://git.code.sf.net/p/tomoyo/tomoyo:
  tomoyo: fallback to realpath if symlink's pathname does not exist
  tomoyo: allow building as a loadable LSM module
  tomoyo: preparation step for building as a loadable LSM module

Pull compute express link (cxl) updates from Dave Jiang:
 "Major changes address HDM decoder initialization from DVSEC ranges,
  refactoring the code related to cxl mailboxes to be independent of the
  memory devices, and adding support for shared upstream link
  access_coordinate calculation, as well as a change to remove locking
  from memory notifier callback.

  In addition, a number of misc cleanups and refactoring of the code are
  also included.

  Address HDM decoder initialization from DVSEC ranges:
   - Only register non-zero DVSEC ranges
   - Remove duplicate implementation of waiting for memory_info_valid
   - Simplify the checking of mem_enabled in  cxl_hdm_decode_init()

  Refactor the code related to cxl mailboxes to be independent of the memory devices:
   - Move cxl headers in include/linux/ to include/cxl
   - Move all mailbox related data to 'struct cxl_mailbox'
   - Refactor mailbox APIs with 'struct cxl_mailbox' as input instead of
     memory device state

  Add support for shared upstream link access_coordinate calculation for
  configurations that have multiple targets under a switch or a root
  port where the aggregated bandwidth can be greater than the upstream
  link of the switch/RP upstream link:
   - Preserve the CDAT access_coordinate from an endpoint
   - Add the support for shared upstream link access_coordinate calculation
   - Add documentation to explain how the calculations are done

  Remove locking from memory notifier callback.

  Misc cleanups:
   - Convert devm_cxl_add_root() to return using ERR_CAST()
   - cxl_test use dev_is_platform() instead of open coding
   - Remove duplicate include of header core.h in core/cdat.c
   - use scoped resource management to drop put_device() for cxl_port
   - Use scoped_guard to drop device_lock() for cxl_port
   - Refactor __devm_cxl_add_port() to drop gotos
   - Rename cxl_setup_parent_dport to cxl_dport_init_aer and
     cxl_dport_map_regs() to cxl_dport_map_ras()
   - Refactor cxl_dport_init_aer() to be more concise
   - Remove duplicate host_bridge->native_aer checking in
     cxl_dport_init_ras_reporting()
   - Fix comment for cxl_query_cmd()"

* tag 'cxl-for-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (21 commits)
  cxl: Add documentation to explain the shared link bandwidth calculation
  cxl: Calculate region bandwidth of targets with shared upstream link
  cxl: Preserve the CDAT access_coordinate for an endpoint
  cxl: Fix comment regarding cxl_query_cmd() return data
  cxl: Convert cxl_internal_send_cmd() to use 'struct cxl_mailbox' as input
  cxl: Move mailbox related bits to the same context
  cxl: move cxl headers to new include/cxl/ directory
  cxl/region: Remove lock from memory notifier callback
  cxl/pci: simplify the check of mem_enabled in cxl_hdm_decode_init()
  cxl/pci: Check Mem_info_valid bit for each applicable DVSEC
  cxl/pci: Remove duplicated implementation of waiting for memory_info_valid
  cxl/pci: Fix to record only non-zero ranges
  cxl/pci: Remove duplicate host_bridge->native_aer checking
  cxl/pci: cxl_dport_map_rch_aer() cleanup
  cxl/pci: Rename cxl_setup_parent_dport() and cxl_dport_map_regs()
  cxl/port: Refactor __devm_cxl_add_port() to drop goto pattern
  cxl/port: Use scoped_guard()/guard() to drop device_lock() for cxl_port
  cxl/port: Use __free() to drop put_device() for cxl_port
  cxl: Remove duplicate included header file core.h
  tools/testing/cxl: Use dev_is_platform()
  ...

Merge tag 'mm-hotfixes-stable-2024-09-27-09-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull  misc fixes from Andrew Morton:
 "19 hotfixes.  13 are cc:stable.

  There's a focus on fixes for the memfd_pin_folios() work which was
  added into 6.11. Apart from that, the usual shower of singleton fixes"

* tag 'mm-hotfixes-stable-2024-09-27-09-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  ocfs2: fix uninit-value in ocfs2_get_block()
  zram: don't free statically defined names
  memory tiers: use default_dram_perf_ref_source in log message
  Revert "list: test: fix tests for list_cut_position()"
  kselftests: mm: fix wrong __NR_userfaultfd value
  compiler.h: specify correct attribute for .rodata..c_jump_table
  mm/damon/Kconfig: update DAMON doc URL
  mm: kfence: fix elapsed time for allocated/freed track
  ocfs2: fix deadlock in ocfs2_get_system_file_inode
  ocfs2: reserve space for inline xattr before attaching reflink tree
  mm: migrate: annotate data-race in migrate_folio_unmap()
  mm/hugetlb: simplify refs in memfd_alloc_folio
  mm/gup: fix memfd_pin_folios alloc race panic
  mm/gup: fix memfd_pin_folios hugetlb page allocation
  mm/hugetlb: fix memfd_pin_folios resv_huge_pages leak
  mm/hugetlb: fix memfd_pin_folios free_huge_pages leak
  mm/filemap: fix filemap_get_folios_contig THP panic
  mm: make SPLIT_PTE_PTLOCKS depend on SMP
  tools: fix shared radix-tree build

Merge tag 'loongarch-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch updates from Huacai Chen:

 - Fix objtool about do_syscall() and Clang

 - Enable generic CPU vulnerabilites support

 - Enable ACPI BGRT handling

 - Rework CPU feature probe from CPUCFG/IOCSR

 - Add ARCH_HAS_SET_MEMORY support

 - Add ARCH_HAS_SET_DIRECT_MAP support

 - Improve hardware page table walker

 - Simplify _percpu_read() and _percpu_write()

 - Add advanced extended IRQ model documentions

 - Some bug fixes and other small changes

* tag 'loongarch-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  Docs/LoongArch: Add advanced extended IRQ model description
  LoongArch: Remove posix_types.h include from sigcontext.h
  LoongArch: Fix memleak in pci_acpi_scan_root()
  LoongArch: Simplify _percpu_read() and _percpu_write()
  LoongArch: Improve hardware page table walker
  LoongArch: Add ARCH_HAS_SET_DIRECT_MAP support
  LoongArch: Add ARCH_HAS_SET_MEMORY support
  LoongArch: Rework CPU feature probe from CPUCFG/IOCSR
  LoongArch: Enable ACPI BGRT handling
  LoongArch: Enable generic CPU vulnerabilites support
  LoongArch: Remove STACK_FRAME_NON_STANDARD(do_syscall)
  LoongArch: Set AS_HAS_THIN_ADD_SUB as y if AS_IS_LLVM
  LoongArch: Enable objtool for Clang
  objtool: Handle frame pointer related instructions

Pull sh updates from John Paul Adrian Glaubitz:
 "The first change by Gaosheng Cui removes unused declarations which
  have been obsoleted since commit 5a4053b2 ("sh: Kill off dead
  boards.") and the second by his colleague Hongbo Li replaces the use
  of the unsafe simple_strtoul() with the safer kstrtoul() function in
  the sh interrupt controller driver code"

* tag 'sh-for-v6.12-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/glaubitz/sh-linux:
  sh: intc: Replace simple_strtoul() with kstrtoul()
  sh: Remove unused declarations for make_maskreg_irq() and irq_mask_register

Pull more xen updates from Juergen Gross:
 "A second round of Xen related changes and features:

   - a small fix of the xen-pciback driver for a warning issued by
     sparse

   - support PCI passthrough when using a PVH dom0

   - enable loading the kernel in PVH mode at arbitrary addresses,
     avoiding conflicts with the memory map when running as a Xen dom0
     using the host memory layout"

* tag 'for-linus-6.12-rc1a-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/pvh: Add 64bit relocation page tables
  x86/kernel: Move page table macros to header
  x86/pvh: Set phys_base when calling xen_prepare_pvh()
  x86/pvh: Make PVH entrypoint PIC for x86-64
  xen: sync elfnote.h from xen tree
  xen/pciback: fix cast to restricted pci_ers_result_t and pci_power_t
  xen/privcmd: Add new syscall to get gsi from dev
  xen/pvh: Setup gsi for passthrough device
  xen/pci: Add a function to reset device for xen

Merge tag 'for-6.12/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mikulas Patocka:

 - Misc VDO fixes

 - Remove unused declarations dm_get_rq_mapinfo() and dm_zone_map_bio()

 - Dm-delay: Improve kernel documentation

 - Dm-crypt: Allow to specify the integrity key size as an option

 - Dm-bufio: Remove pointless NULL check

 - Small code cleanups: Use ERR_CAST; remove unlikely() around IS_ERR;
   use __assign_bit

 - Dm-integrity: Fix gcc 5 warning; convert comma to semicolon; fix
   smatch warning

 - Dm-integrity: Support recalculation in the 'I' mode

 - Revert "dm: requeue IO if mapping table not yet available"

 - Dm-crypt: Small refactoring to make the code more readable

 - Dm-cache: Remove pointless error check

 - Dm: Fix spelling errors

 - Dm-verity: Restart or panic on an I/O error if restart or panic was
   requested

 - Dm-verity: Fallback to platform keyring also if key in trusted
   keyring is rejected

* tag 'for-6.12/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (26 commits)
  dm verity: fallback to platform keyring also if key in trusted keyring is rejected
  dm-verity: restart or panic on an I/O error
  dm: fix spelling errors
  dm-cache: remove pointless error check
  dm vdo: handle unaligned discards correctly
  dm vdo indexer: Convert comma to semicolon
  dm-crypt: Use common error handling code in crypt_set_keyring_key()
  dm-crypt: Use up_read() together with key_put() only once in crypt_set_keyring_key()
  Revert "dm: requeue IO if mapping table not yet available"
  dm-integrity: check mac_size against HASH_MAX_DIGESTSIZE in sb_mac()
  dm-integrity: support recalculation in the 'I' mode
  dm integrity: Convert comma to semicolon
  dm integrity: fix gcc 5 warning
  dm: Make use of __assign_bit() API
  dm integrity: Remove extra unlikely helper
  dm: Convert to use ERR_CAST()
  dm bufio: Remove NULL check of list_entry()
  dm-crypt: Allow to specify the integrity key size as option
  dm: Remove unused declaration and empty definition "dm_zone_map_bio"
  dm delay: enhance kernel documentation
  ...

Pull ata fixes from Damien Le Moal:

 - Fix a NULL pointer dereference introduced by the recent cleanups of
   the command duration limits feature handling (me)

 - Fix incorrect generation of the mode sense data for the
   ALL_SUB_MPAGES page (me)

* tag 'ata-6.12-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux:
  ata: libata-scsi: Fix ata_msense_control() CDL page reporting
  ata: libata-scsi: Fix ata_msense_control_spgt2()

Merge tag 'driver-core-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is a small set of patches for the driver core code for 6.12-rc1.

  This set is the one that caused the most delay on my side, due to lots
  of last-minute reports of problems in the async shutdown feature that
  was added. In the end, I've reverted all of the patches in that series
  so we are back to "normal" and the patch set is being reworked for the
  next merge window.

  Other than the async shutdown patches that were reverted, included in
  here are:

   - minor driver core cleanups

   - minor driver core bus and class api cleanups and simplifications
     for some callbacks

   - some const markings of structures

   - other even more minor cleanups

  All of these, including the last minute reverts, have been in
  linux-next, but all of the reports of problems in linux-next were
  before the reverts happened. After the reverts, all is good"

* tag 'driver-core-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (32 commits)
  Revert "driver core: don't always lock parent in shutdown"
  Revert "driver core: separate function to shutdown one device"
  Revert "driver core: shut down devices asynchronously"
  Revert "nvme-pci: Make driver prefer asynchronous shutdown"
  Revert "driver core: fix async device shutdown hang"
  driver core: fix async device shutdown hang
  driver core: attribute_container: Remove unused functions
  driver core: Trivially simplify ((struct device_private *)curr)->device->p to @curr
  devres: Correclty strip percpu address space of devm_free_percpu() argument
  driver core: Make parameter check consistent for API cluster device_(for_each|find)_child()
  bus: fsl-mc: make fsl_mc_bus_type const
  nvme-pci: Make driver prefer asynchronous shutdown
  driver core: shut down devices asynchronously
  driver core: separate function to shutdown one device
  driver core: don't always lock parent in shutdown
  platform: Make platform_bus_type constant
  driver core: class: Check namespace relevant parameters in class_register()
  driver:base:core: Adding a "Return:" line in comment for device_link_add()
  drivers/base: Introduce device_match_t for device finding APIs
  firmware_loader: Block path traversal
  ...

no_llseek had been defined to NULL two years ago, in commit 868941b1
("fs: remove no_llseek")

To quote that commit,

  At -rc1 we'll need do a mechanical removal of no_llseek -

  git grep -l -w no_llseek | grep -v porting.rst | while read i; do
	sed -i '/\<no_llseek\>/d' $i
  done

  would do it.

Unfortunately, that hadn't been done.  Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
	.llseek = no_llseek,
so it's obviously safe.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The SHA-512 shash TFM is used only briefly during Session Setup stage,
when computing SMB 3.1.1 preauth hash.

There's no need to keep it allocated in servers' secmech the whole time,
so keep its lifetime inside smb311_update_preauth_hash().

This also makes smb311_crypto_shash_allocate() redundant, so expose
smb3_crypto_shash_allocate() and use that.
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>

The HMAC-MD5 shash TFM is used only briefly during Session Setup stage,
when computing NTLMv2 hashes.

There's no need to keep it allocated in servers' secmech the whole time,
so keep its lifetime inside setup_ntlmv2_rsp().
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>

When having several mounts that share same credential and the client
couldn't re-establish an SMB session due to an expired kerberos ticket
or rotated password, smb2_calc_signature() will end up flooding dmesg
when not finding SMB sessions to calculate signatures.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

For extra channels, point ->secmech.{enc,dec} to the primary
server ones.
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>

Doing an async decryption (large read) crashes with a
slab-use-after-free way down in the crypto API.

Reproducer:
    # mount.cifs -o ...,seal,esize=1 //srv/share /mnt
    # dd if=/mnt/largefile of=/dev/null
    ...
    [  194.196391] ==================================================================
    [  194.196844] BUG: KASAN: slab-use-after-free in gf128mul_4k_lle+0xc1/0x110
    [  194.197269] Read of size 8 at addr ffff888112bd0448 by task kworker/u77:2/899
    [  194.197707]
    [  194.197818] CPU: 12 UID: 0 PID: 899 Comm: kworker/u77:2 Not tainted 6.11.0-lku-00028-gfca3ca14a17a-dirty #43
    [  194.198400] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-3-gd478f380-prebuilt.qemu.org 04/01/2014
    [  194.199046] Workqueue: smb3decryptd smb2_decrypt_offload [cifs]
    [  194.200032] Call Trace:
    [  194.200191]  <TASK>
    [  194.200327]  dump_stack_lvl+0x4e/0x70
    [  194.200558]  ? gf128mul_4k_lle+0xc1/0x110
    [  194.200809]  print_report+0x174/0x505
    [  194.201040]  ? __pfx__raw_spin_lock_irqsave+0x10/0x10
    [  194.201352]  ? srso_return_thunk+0x5/0x5f
    [  194.201604]  ? __virt_addr_valid+0xdf/0x1c0
    [  194.201868]  ? gf128mul_4k_lle+0xc1/0x110
    [  194.202128]  kasan_report+0xc8/0x150
    [  194.202361]  ? gf128mul_4k_lle+0xc1/0x110
    [  194.202616]  gf128mul_4k_lle+0xc1/0x110
    [  194.202863]  ghash_update+0x184/0x210
    [  194.203103]  shash_ahash_update+0x184/0x2a0
    [  194.203377]  ? __pfx_shash_ahash_update+0x10/0x10
    [  194.203651]  ? srso_return_thunk+0x5/0x5f
    [  194.203877]  ? crypto_gcm_init_common+0x1ba/0x340
    [  194.204142]  gcm_hash_assoc_remain_continue+0x10a/0x140
    [  194.204434]  crypt_message+0xec1/0x10a0 [cifs]
    [  194.206489]  ? __pfx_crypt_message+0x10/0x10 [cifs]
    [  194.208507]  ? srso_return_thunk+0x5/0x5f
    [  194.209205]  ? srso_return_thunk+0x5/0x5f
    [  194.209925]  ? srso_return_thunk+0x5/0x5f
    [  194.210443]  ? srso_return_thunk+0x5/0x5f
    [  194.211037]  decrypt_raw_data+0x15f/0x250 [cifs]
    [  194.212906]  ? __pfx_decrypt_raw_data+0x10/0x10 [cifs]
    [  194.214670]  ? srso_return_thunk+0x5/0x5f
    [  194.215193]  smb2_decrypt_offload+0x12a/0x6c0 [cifs]

This is because TFM is being used in parallel.

Fix this by allocating a new AEAD TFM for async decryption, but keep
the existing one for synchronous READ cases (similar to what is done
in smb3_calc_signature()).

Also remove the calls to aead_request_set_callback() and
crypto_wait_req() since it's always going to be a synchronous operation.
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>

In netfslib, a buffered writeback operation has a 'write queue' of folios
that are being written, held in a linear sequence of folio_queue structs.
The 'issuer' adds new folio_queues on the leading edge of the queue and
populates each one progressively; the 'collector' pops them off the
trailing edge and discards them and the folios they point to as they are
consumed.

The queue is required to always retain at least one folio_queue structure.
This allows the queue to be accessed without locking and with just a bit of
barriering.

When a new subrequest is prepared, its ->io_iter iterator is pointed at the
current end of the write queue and then the iterator is extended as more
data is added to the queue until the subrequest is committed.

Now, the problem is that the folio_queue at the leading edge of the write
queue when a subrequest is prepared might have been entirely consumed - but
not yet removed from the queue as it is the only remaining one and is
preventing the queue from collapsing.

So, what happens is that subreq->io_iter is pointed at the spent
folio_queue, then a new folio_queue is added, and, at that point, the
collector is at entirely at liberty to immediately delete the spent
folio_queue.

This leaves the subreq->io_iter pointing at a freed object.  If the system
is lucky, iterate_folioq() sees ->io_iter, sees the as-yet uncorrupted
freed object and advances to the next folio_queue in the queue.

In the case seen, however, the freed object gets recycled and put back onto
the queue at the tail and filled to the end.  This confuses
iterate_folioq() and it tries to step ->next, which may be NULL - resulting
in an oops.

Fix this by the following means:

 (1) When preparing a write subrequest, make sure there's a folio_queue
     struct with space in it at the leading edge of the queue.  A function
     to make space is split out of the function to append a folio so that
     it can be called for this purpose.

 (2) If the request struct iterator is pointing to a completely spent
     folio_queue when we make space, then advance the iterator to the newly
     allocated folio_queue.  The subrequest's iterator will then be set
     from this.

The oops could be triggered using the generic/346 xfstest with a filesystem
on9P over TCP with cache=loose.  The oops looked something like:

 BUG: kernel NULL pointer dereference, address: 0000000000000008
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 ...
 RIP: 0010:_copy_from_iter+0x2db/0x530
 ...
 Call Trace:
  <TASK>
 ...
  p9pdu_vwritef+0x3d8/0x5d0
  p9_client_prepare_req+0xa8/0x140
  p9_client_rpc+0x81/0x280
  p9_client_write+0xcf/0x1c0
  v9fs_issue_write+0x87/0xc0
  netfs_advance_write+0xa0/0xb0
  netfs_write_folio.isra.0+0x42d/0x500
  netfs_writepages+0x15a/0x1f0
  do_writepages+0xd1/0x220
  filemap_fdatawrite_wbc+0x5c/0x80
  v9fs_mmap_vm_close+0x7d/0xb0
  remove_vma+0x35/0x70
  vms_complete_munmap_vmas+0x11a/0x170
  do_vmi_align_munmap+0x17d/0x1c0
  do_vmi_munmap+0x13e/0x150
  __vm_munmap+0x92/0xd0
  __x64_sys_munmap+0x17/0x20
  do_syscall_64+0x80/0xe0
  entry_SYSCALL_64_after_hwframe+0x71/0x79

This also fixed a similar-looking issue with cifs and generic/074.

Fixes: cd0277ed ("netfs: Use new folio_queue data type and iterator instead of xarray iter")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202409180928.f20b5a08-oliver.sang@intel.com
Closes: https://lore.kernel.org/oe-lkp/202409131438.3f225fbf-oliver.sang@intel.comSigned-off-by: David Howells <dhowells@redhat.com>
Tested-by: kernel test robot <oliver.sang@intel.com>
cc: Eric Van Hensbergen <ericvh@kernel.org>
cc: Latchesar Ionkov <lucho@ionkov.net>
cc: Dominique Martinet <asmadeus@codewreck.org>
cc: Christian Schoenebeck <linux_oss@crudebyte.com>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: v9fs@lists.linux.dev
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>

syzbot reported an uninit-value BUG:

BUG: KMSAN: uninit-value in ocfs2_get_block+0xed2/0x2710 fs/ocfs2/aops.c:159
ocfs2_get_block+0xed2/0x2710 fs/ocfs2/aops.c:159
do_mpage_readpage+0xc45/0x2780 fs/mpage.c:225
mpage_readahead+0x43f/0x840 fs/mpage.c:374
ocfs2_readahead+0x269/0x320 fs/ocfs2/aops.c:381
read_pages+0x193/0x1110 mm/readahead.c:160
page_cache_ra_unbounded+0x901/0x9f0 mm/readahead.c:273
do_page_cache_ra mm/readahead.c:303 [inline]
force_page_cache_ra+0x3b1/0x4b0 mm/readahead.c:332
force_page_cache_readahead mm/internal.h:347 [inline]
generic_fadvise+0x6b0/0xa90 mm/fadvise.c:106
vfs_fadvise mm/fadvise.c:185 [inline]
ksys_fadvise64_64 mm/fadvise.c:199 [inline]
__do_sys_fadvise64 mm/fadvise.c:214 [inline]
__se_sys_fadvise64 mm/fadvise.c:212 [inline]
__x64_sys_fadvise64+0x1fb/0x3a0 mm/fadvise.c:212
x64_sys_call+0xe11/0x3ba0
arch/x86/include/generated/asm/syscalls_64.h:222
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

This is because when ocfs2_extent_map_get_blocks() fails, p_blkno is
uninitialized.  So the error log will trigger the above uninit-value
access.

The error log is out-of-date since get_blocks() was removed long time ago.
And the error code will be logged in ocfs2_extent_map_get_blocks() once
ocfs2_get_cluster() fails, so fix this by only logging inode and block.

Link: https://syzkaller.appspot.com/bug?extid=9709e73bae885b05314b
Link: https://lkml.kernel.org/r/20240925090600.3643376-1-joseph.qi@linux.alibaba.com
Fixes: ccd979bd ("[PATCH] OCFS2: The Second Oracle Cluster Filesystem")
Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reported-by: syzbot+9709e73bae885b05314b@syzkaller.appspotmail.com
Tested-by: syzbot+9709e73bae885b05314b@syzkaller.appspotmail.com
Cc: Heming Zhao <heming.zhao@suse.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

When CONFIG_ZRAM_MULTI_COMP isn't set ZRAM_SECONDARY_COMP can hold
default_compressor, because it's the same offset as ZRAM_PRIMARY_COMP, so
we need to make sure that we don't attempt to kfree() the statically
defined compressor name.

This is detected by KASAN.

==================================================================
  Call trace:
   kfree+0x60/0x3a0
   zram_destroy_comps+0x98/0x198 [zram]
   zram_reset_device+0x22c/0x4a8 [zram]
   reset_store+0x1bc/0x2d8 [zram]
   dev_attr_store+0x44/0x80
   sysfs_kf_write+0xfc/0x188
   kernfs_fop_write_iter+0x28c/0x428
   vfs_write+0x4dc/0x9b8
   ksys_write+0x100/0x1f8
   __arm64_sys_write+0x74/0xb8
   invoke_syscall+0xd8/0x260
   el0_svc_common.constprop.0+0xb4/0x240
   do_el0_svc+0x48/0x68
   el0_svc+0x40/0xc8
   el0t_64_sync_handler+0x120/0x130
   el0t_64_sync+0x190/0x198
==================================================================

Link: https://lkml.kernel.org/r/20240923164843.1117010-1-andrej.skvortzov@gmail.com
Fixes: 684826f8 ("zram: free secondary algorithms names")
Signed-off-by: Andrey Skvortsov <andrej.skvortzov@gmail.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reported-by: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com>
Closes: https://lore.kernel.org/lkml/57130e48-dbb6-4047-a8c7-ebf5aaea93f4@linux.vnet.ibm.com/Tested-by: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com>
Cc: Chris Li <chrisl@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Commit 3718c02d ("acpi, hmat: calculate abstract distance with HMAT")
added a default_dram_perf_ref_source variable that was initialized but
never used.  This causes kmemleak to report the following memory leak:

unreferenced object 0xff11000225a47b60 (size 16):
  comm "swapper/0", pid 1, jiffies 4294761654
  hex dump (first 16 bytes):
    41 43 50 49 20 48 4d 41 54 00 c1 4b 7d b7 75 7c  ACPI HMAT..K}.u|
  backtrace (crc e6d0e7b2):
    [<ffffffff95d5afdb>] __kmalloc_node_track_caller_noprof+0x36b/0x440
    [<ffffffff95c276d6>] kstrdup+0x36/0x60
    [<ffffffff95dfabfa>] mt_set_default_dram_perf+0x23a/0x2c0
    [<ffffffff9ad64733>] hmat_init+0x2b3/0x660
    [<ffffffff95203cec>] do_one_initcall+0x11c/0x5c0
    [<ffffffff9ac9cfc4>] do_initcalls+0x1b4/0x1f0
    [<ffffffff9ac9d52e>] kernel_init_freeable+0x4ae/0x520
    [<ffffffff97c789cc>] kernel_init+0x1c/0x150
    [<ffffffff952aecd1>] ret_from_fork+0x31/0x70
    [<ffffffff9520b18a>] ret_from_fork_asm+0x1a/0x30

This reminds us that we forget to use the performance data source
information.  So, use the variable in the error log message to help
identify the root cause of inconsistent performance number.

Link: https://lkml.kernel.org/r/87y13mvo0n.fsf@yhuang6-desk2.ccr.corp.intel.com
Fixes: 3718c02d ("acpi, hmat: calculate abstract distance with HMAT")
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reported-by: Waiman Long <longman@redhat.com>
Acked-by: Waiman Long <longman@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

This reverts commit e620799c.

The commit introduces unit test failures.

     Expected cur == &entries[i], but
         cur == 0000037fffadfd80
         &entries[i] == 0000037fffadfd60
     # list_test_list_cut_position: pass:0 fail:1 skip:0 total:1
     not ok 21 list_test_list_cut_position
     # list_test_list_cut_before: EXPECTATION FAILED at lib/list-test.c:444
     Expected cur == &entries[i], but
         cur == 0000037fffa9fd70
         &entries[i] == 0000037fffa9fd60
     # list_test_list_cut_before: EXPECTATION FAILED at lib/list-test.c:444
     Expected cur == &entries[i], but
         cur == 0000037fffa9fd80
         &entries[i] == 0000037fffa9fd70

Revert it.

Link: https://lkml.kernel.org/r/20240922150507.553814-1-linux@roeck-us.net
Fixes: e620799c ("list: test: fix tests for list_cut_position()")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: I Hsin Cheng <richard120310@gmail.com>
Cc: David Gow <davidgow@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

grep -rnIF "#define __NR_userfaultfd"
tools/include/uapi/asm-generic/unistd.h:681:#define __NR_userfaultfd 282
arch/x86/include/generated/uapi/asm/unistd_32.h:374:#define
__NR_userfaultfd 374
arch/x86/include/generated/uapi/asm/unistd_64.h:327:#define
__NR_userfaultfd 323
arch/x86/include/generated/uapi/asm/unistd_x32.h:282:#define
__NR_userfaultfd (__X32_SYSCALL_BIT + 323)
arch/arm/include/generated/uapi/asm/unistd-eabi.h:347:#define
__NR_userfaultfd (__NR_SYSCALL_BASE + 388)
arch/arm/include/generated/uapi/asm/unistd-oabi.h:359:#define
__NR_userfaultfd (__NR_SYSCALL_BASE + 388)
include/uapi/asm-generic/unistd.h:681:#define __NR_userfaultfd 282

The number is dependent on the architecture. The above data shows that:
x86	374
x86_64	323

The value of __NR_userfaultfd was changed to 282 when asm-generic/unistd.h
was included.  It makes the test to fail every time as the correct number
of this syscall on x86_64 is 323.  Fix the header to asm/unistd.h.

Link: https://lkml.kernel.org/r/20240923053836.3270393-1-usama.anjum@collabora.com
Fixes: a5c6bc59 ("selftests/mm: remove local __NR_* definitions")
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Currently, there is an assembler message when generating kernel/bpf/core.o
under CONFIG_OBJTOOL with LoongArch compiler toolchain:

  Warning: setting incorrect section attributes for .rodata..c_jump_table

This is because the section ".rodata..c_jump_table" should be readonly,
but there is a "W" (writable) part of the flags:

  $ readelf -S kernel/bpf/core.o | grep -A 1 "rodata..c"
  [34] .rodata..c_j[...] PROGBITS         0000000000000000  0000d2e0
       0000000000000800  0000000000000000  WA       0     0     8

There is no above issue on x86 due to the generated section flag is only
"A" (allocatable). In order to silence the warning on LoongArch, specify
the attribute like ".rodata..c_jump_table,\"a\",@progbits #" explicitly,
then the section attribute of ".rodata..c_jump_table" must be readonly
in the kernel/bpf/core.o file.

Before:

  $ objdump -h kernel/bpf/core.o | grep -A 1 "rodata..c"
   21 .rodata..c_jump_table 00000800  0000000000000000  0000000000000000  0000d2e0  2**3
                  CONTENTS, ALLOC, LOAD, RELOC, DATA

After:

  $ objdump -h kernel/bpf/core.o | grep -A 1 "rodata..c"
   21 .rodata..c_jump_table 00000800  0000000000000000  0000000000000000  0000d2e0  2**3
                  CONTENTS, ALLOC, LOAD, RELOC, READONLY, DATA

By the way, AFAICT, maybe the root cause is related with the different
compiler behavior of various archs, so to some extent this change is a
workaround for LoongArch, and also there is no effect for x86 which is the
only port supported by objtool before LoongArch with this patch.

Link: https://lkml.kernel.org/r/20240924062710.1243-1-yangtiezhu@loongson.cnSigned-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>	[6.9+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The old URL doesn't really work anymore and as the documentation has been
integrated in the main kernel documentation site, change the URL to point
to that.

Link: https://lkml.kernel.org/r/20240924082331.11499-1-didi.debian@cknow.orgSigned-off-by: Diederik de Haas <didi.debian@cknow.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Fix elapsed time for the allocated/freed track introduced by commit
62e73fd8.

Link: https://lkml.kernel.org/r/20240924085004.75401-1-qiwu.chen@transsion.com
Fixes: 62e73fd8 ("mm: kfence: print the elapsed time for allocated/freed track")
Signed-off-by: qiwu.chen <qiwu.chen@transsion.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

syzbot has found a possible deadlock in ocfs2_get_system_file_inode [1].

The scenario is depicted here,

	CPU0					CPU1
lock(&ocfs2_file_ip_alloc_sem_key);
                               lock(&osb->system_file_mutex);
                               lock(&ocfs2_file_ip_alloc_sem_key);
lock(&osb->system_file_mutex);

The function calls which could lead to this are:

CPU0
ocfs2_mknod - lock(&ocfs2_file_ip_alloc_sem_key);
.
.
.
ocfs2_get_system_file_inode - lock(&osb->system_file_mutex);

CPU1 -
ocfs2_fill_super - lock(&osb->system_file_mutex);
.
.
.
ocfs2_read_virt_blocks - lock(&ocfs2_file_ip_alloc_sem_key);

This issue can be resolved by making the down_read -> down_read_try
in the ocfs2_read_virt_blocks.

[1] https://syzkaller.appspot.com/bug?extid=e0055ea09f1f5e6fabdd

Link: https://lkml.kernel.org/r/20240924093257.7181-1-pvmohammedanees2003@gmail.comSigned-off-by: Mohammed Anees <pvmohammedanees2003@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reported-by: <syzbot+e0055ea09f1f5e6fabdd@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=e0055ea09f1f5e6fabdd
Tested-by: syzbot+e0055ea09f1f5e6fabdd@syzkaller.appspotmail.com
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc:  <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

One of our customers reported a crash and a corrupted ocfs2 filesystem. 
The crash was due to the detection of corruption.  Upon troubleshooting,
the fsck -fn output showed the below corruption

[EXTENT_LIST_FREE] Extent list in owner 33080590 claims 230 as the next free chain record,
but fsck believes the largest valid value is 227.  Clamp the next record value? n

The stat output from the debugfs.ocfs2 showed the following corruption
where the "Next Free Rec:" had overshot the "Count:" in the root metadata
block.

        Inode: 33080590   Mode: 0640   Generation: 2619713622 (0x9c25a856)
        FS Generation: 904309833 (0x35e6ac49)
        CRC32: 00000000   ECC: 0000
        Type: Regular   Attr: 0x0   Flags: Valid
        Dynamic Features: (0x16) HasXattr InlineXattr Refcounted
        Extended Attributes Block: 0  Extended Attributes Inline Size: 256
        User: 0 (root)   Group: 0 (root)   Size: 281320357888
        Links: 1   Clusters: 141738
        ctime: 0x66911b56 0x316edcb8 -- Fri Jul 12 06:02:30.829349048 2024
        atime: 0x66911d6b 0x7f7a28d -- Fri Jul 12 06:11:23.133669517 2024
        mtime: 0x66911b56 0x12ed75d7 -- Fri Jul 12 06:02:30.317552087 2024
        dtime: 0x0 -- Wed Dec 31 17:00:00 1969
        Refcount Block: 2777346
        Last Extblk: 2886943   Orphan Slot: 0
        Sub Alloc Slot: 0   Sub Alloc Bit: 14
        Tree Depth: 1   Count: 227   Next Free Rec: 230
        ## Offset        Clusters       Block#
        0  0             2310           2776351
        1  2310          2139           2777375
        2  4449          1221           2778399
        3  5670          731            2779423
        4  6401          566            2780447
        .......          ....           .......
        .......          ....           .......

The issue was in the reflink workfow while reserving space for inline
xattr.  The problematic function is ocfs2_reflink_xattr_inline().  By the
time this function is called the reflink tree is already recreated at the
destination inode from the source inode.  At this point, this function
reserves space for inline xattrs at the destination inode without even
checking if there is space at the root metadata block.  It simply reduces
the l_count from 243 to 227 thereby making space of 256 bytes for inline
xattr whereas the inode already has extents beyond this index (in this
case up to 230), thereby causing corruption.

The fix for this is to reserve space for inline metadata at the destination
inode before the reflink tree gets recreated. The customer has verified the
fix.

Link: https://lkml.kernel.org/r/20240918063844.1830332-1-gautham.ananthakrishna@oracle.com
Fixes: ef962df0 ("ocfs2: xattr: fix inlined xattr reflink")
Signed-off-by: Gautham Ananthakrishna <gautham.ananthakrishna@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

I found a report from syzbot [1]

This report shows that the value can be changed, but in reality, the
value of __folio_set_movable() cannot be changed because it holds the
folio refcount.

Therefore, it is appropriate to add an annotate to make KCSAN
ignore that data-race.

[1]

==================================================================
BUG: KCSAN: data-race in __filemap_remove_folio / migrate_pages_batch

write to 0xffffea0004b81dd8 of 8 bytes by task 6348 on cpu 0:
 page_cache_delete mm/filemap.c:153 [inline]
 __filemap_remove_folio+0x1ac/0x2c0 mm/filemap.c:233
 filemap_remove_folio+0x6b/0x1f0 mm/filemap.c:265
 truncate_inode_folio+0x42/0x50 mm/truncate.c:178
 shmem_undo_range+0x25b/0xa70 mm/shmem.c:1028
 shmem_truncate_range mm/shmem.c:1144 [inline]
 shmem_evict_inode+0x14d/0x530 mm/shmem.c:1272
 evict+0x2f0/0x580 fs/inode.c:731
 iput_final fs/inode.c:1883 [inline]
 iput+0x42a/0x5b0 fs/inode.c:1909
 dentry_unlink_inode+0x24f/0x260 fs/dcache.c:412
 __dentry_kill+0x18b/0x4c0 fs/dcache.c:615
 dput+0x5c/0xd0 fs/dcache.c:857
 __fput+0x3fb/0x6d0 fs/file_table.c:439
 ____fput+0x1c/0x30 fs/file_table.c:459
 task_work_run+0x13a/0x1a0 kernel/task_work.c:228
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xbe/0x130 kernel/entry/common.c:218
 do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffea0004b81dd8 of 8 bytes by task 6342 on cpu 1:
 __folio_test_movable include/linux/page-flags.h:699 [inline]
 migrate_folio_unmap mm/migrate.c:1199 [inline]
 migrate_pages_batch+0x24c/0x1940 mm/migrate.c:1797
 migrate_pages_sync mm/migrate.c:1963 [inline]
 migrate_pages+0xff1/0x1820 mm/migrate.c:2072
 do_mbind mm/mempolicy.c:1390 [inline]
 kernel_mbind mm/mempolicy.c:1533 [inline]
 __do_sys_mbind mm/mempolicy.c:1607 [inline]
 __se_sys_mbind+0xf76/0x1160 mm/mempolicy.c:1603
 __x64_sys_mbind+0x78/0x90 mm/mempolicy.c:1603
 x64_sys_call+0x2b4d/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:238
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff888127601078 -> 0x0000000000000000

Link: https://lkml.kernel.org/r/20240924130053.107490-1-aha310510@gmail.com
Fixes: 7e2a5e5a ("mm: migrate: use __folio_test_movable()")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The folio_try_get in memfd_alloc_folio is not necessary.  Delete it, and
delete the matching folio_put in memfd_pin_folios.  This also avoids
leaking a ref if the memfd_alloc_folio call to hugetlb_add_to_page_cache
fails.  That error path is also broken in a second way -- when its
folio_put causes the ref to become 0, it will implicitly call
free_huge_folio, but then the path *explicitly* calls free_huge_folio. 
Delete the latter.

This is a continuation of the fix
  "mm/hugetlb: fix memfd_pin_folios free_huge_pages leak"

[steven.sistare@oracle.com: remove explicit call to free_huge_folio(), per Matthew]
  Link: https://lkml.kernel.org/r/Zti-7nPVMcGgpcbi@casper.infradead.org
  Link: https://lkml.kernel.org/r/1725481920-82506-1-git-send-email-steven.sistare@oracle.com
Link: https://lkml.kernel.org/r/1725478868-61732-1-git-send-email-steven.sistare@oracle.com
Fixes: 89c1905d ("mm/gup: introduce memfd_pin_folios() for pinning memfd folios")
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Suggested-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

If memfd_pin_folios tries to create a hugetlb page, but someone else
already did, then folio gets the value -EEXIST here:

        folio = memfd_alloc_folio(memfd, start_idx);
        if (IS_ERR(folio)) {
                ret = PTR_ERR(folio);
                if (ret != -EEXIST)
                        goto err;

then on the next trip through the "while start_idx" loop we panic here:

        if (folio) {
                folio_put(folio);

To fix, set the folio to NULL on error.

Link: https://lkml.kernel.org/r/1725373521-451395-6-git-send-email-steven.sistare@oracle.com
Fixes: 89c1905d ("mm/gup: introduce memfd_pin_folios() for pinning memfd folios")
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Acked-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

When memfd_pin_folios -> memfd_alloc_folio creates a hugetlb page, the
index is wrong.  The subsequent call to filemap_get_folios_contig thus
cannot find it, and fails, and memfd_pin_folios loops forever.  To fix,
adjust the index for the huge_page_order.

memfd_alloc_folio also forgets to unlock the folio, so the next touch of
the page calls hugetlb_fault which blocks forever trying to take the lock.
Unlock it.

Link: https://lkml.kernel.org/r/1725373521-451395-5-git-send-email-steven.sistare@oracle.com
Fixes: 89c1905d ("mm/gup: introduce memfd_pin_folios() for pinning memfd folios")
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Acked-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

memfd_pin_folios followed by unpin_folios leaves resv_huge_pages elevated
if the pages were not already faulted in.  During a normal page fault,
resv_huge_pages is consumed here:

hugetlb_fault()
  alloc_hugetlb_folio()
    dequeue_hugetlb_folio_vma()
      dequeue_hugetlb_folio_nodemask()
        dequeue_hugetlb_folio_node_exact()
          free_huge_pages--
      resv_huge_pages--

During memfd_pin_folios, the page is created by calling
alloc_hugetlb_folio_nodemask instead of alloc_hugetlb_folio, and
resv_huge_pages is not modified:

memfd_alloc_folio()
  alloc_hugetlb_folio_nodemask()
    dequeue_hugetlb_folio_nodemask()
      dequeue_hugetlb_folio_node_exact()
        free_huge_pages--

alloc_hugetlb_folio_nodemask has other callers that must not modify
resv_huge_pages.  Therefore, to fix, define an alternate version of
alloc_hugetlb_folio_nodemask for this call site that adjusts
resv_huge_pages.

Link: https://lkml.kernel.org/r/1725373521-451395-4-git-send-email-steven.sistare@oracle.com
Fixes: 89c1905d ("mm/gup: introduce memfd_pin_folios() for pinning memfd folios")
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Acked-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

memfd_pin_folios followed by unpin_folios fails to restore free_huge_pages
if the pages were not already faulted in, because the folio refcount for
pages created by memfd_alloc_folio never goes to 0.  memfd_pin_folios
needs another folio_put to undo the folio_try_get below:

memfd_alloc_folio()
  alloc_hugetlb_folio_nodemask()
    dequeue_hugetlb_folio_nodemask()
      dequeue_hugetlb_folio_node_exact()
        folio_ref_unfreeze(folio, 1);    ; adds 1 refcount
  folio_try_get()                        ; adds 1 refcount
  hugetlb_add_to_page_cache()            ; adds 512 refcount (on x86)

With the fix, after memfd_pin_folios + unpin_folios, the refcount for the
(unfaulted) page is 512, which is correct, as the refcount for a faulted
unpinned page is 513.

Link: https://lkml.kernel.org/r/1725373521-451395-3-git-send-email-steven.sistare@oracle.com
Fixes: 89c1905d ("mm/gup: introduce memfd_pin_folios() for pinning memfd folios")
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Acked-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Patch series "memfd-pin huge page fixes".

Fix multiple bugs that occur when using memfd_pin_folios with hugetlb
pages and THP.  The hugetlb bugs only bite when the page is not yet
faulted in when memfd_pin_folios is called.  The THP bug bites when the
starting offset passed to memfd_pin_folios is not huge page aligned.  See
the commit messages for details.


This patch (of 5):

memfd_pin_folios on memory backed by THP panics if the requested start
offset is not huge page aligned:

BUG: kernel NULL pointer dereference, address: 0000000000000036
RIP: 0010:filemap_get_folios_contig+0xdf/0x290
RSP: 0018:ffffc9002092fbe8 EFLAGS: 00010202
RAX: 0000000000000002 RBX: 0000000000000002 RCX: 0000000000000002

The fault occurs here, because xas_load returns a folio with value 2:

    filemap_get_folios_contig()
        for (folio = xas_load(&xas); folio && xas.xa_index <= end;
                        folio = xas_next(&xas)) {
                ...
                if (!folio_try_get(folio))   <-- BOOM

"2" is an xarray sibling entry.  We get it because memfd_pin_folios does
not round the indices passed to filemap_get_folios_contig to huge page
boundaries for THP, so we load from the middle of a huge page range see a
sibling.  (It does round for hugetlbfs, at the is_file_hugepages test).

To fix, if the folio is a sibling, then return the next index as the
starting point for the next call to filemap_get_folios_contig.

Link: https://lkml.kernel.org/r/1725373521-451395-1-git-send-email-steven.sistare@oracle.com
Link: https://lkml.kernel.org/r/1725373521-451395-2-git-send-email-steven.sistare@oracle.com
Fixes: 89c1905d ("mm/gup: introduce memfd_pin_folios() for pinning memfd folios")
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: Vivek Kasireddy <vivek.kasireddy@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

SPLIT_PTE_PTLOCKS depends on "NR_CPUS >= 4".  Unfortunately, that
evaluates to true if there is no NR_CPUS configuration option.  This
results in CONFIG_SPLIT_PTE_PTLOCKS=y for mac_defconfig.  This in turn
causes the m68k "q800" and "virt" machines to crash in qemu if debugging
options are enabled.

Making CONFIG_SPLIT_PTE_PTLOCKS dependent on the existence of NR_CPUS does
not work since a dependency on the existence of a numeric Kconfig entry
always evaluates to false.  Example:

config HAVE_NO_NR_CPUS
       def_bool y
       depends on !NR_CPUS

After adding this to a Kconfig file, "make defconfig" includes:
$ grep NR_CPUS .config
CONFIG_NR_CPUS=64
CONFIG_HAVE_NO_NR_CPUS=y

Defining NR_CPUS for m68k does not help either since many architectures
define NR_CPUS only for SMP configurations.

Make SPLIT_PTE_PTLOCKS depend on SMP instead to solve the problem.

Link: https://lkml.kernel.org/r/20240924154205.1491376-1-linux@roeck-us.net
Fixes: 394290cb ("mm: turn USE_SPLIT_PTE_PTLOCKS / USE_SPLIT_PTE_PTLOCKS into Kconfig options")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>