Mateusz reports that glibc turns 'fstat()' calls into 'fstatat()', and
that seems to have been going on for quite a long time due to glibc
having tried to simplify its stat logic into just one point.

This turns out to cause completely unnecessary overhead, where we then
go off and allocate the kernel side pathname, and actually look up the
empty path.  Sure, our path lookup is quite optimized, but it still
causes a fair bit of allocation overhead and a couple of completely
unnecessary rounds of lockref accesses etc.

This is all hopefully getting fixed in user space, and there is a patch
floating around for just having glibc use the native fstat() system
call.  But even with the current situation we can at least improve on
things by catching the situation and short-circuiting it.

Note that this is still measurably slower than just a plain 'fstat()',
since just checking that the filename is actually empty is somewhat
expensive due to inevitable user space access overhead from the kernel
(ie verifying pointers, and SMAP on x86).  But it's still quite a bit
faster than actually looking up the path for real.

To quote numers from Mateusz:
 "Sapphire Rapids, will-it-scale, ops/s

  stock fstat	5088199
  patched fstat	7625244	(+49%)
  real fstat	8540383	(+67% / +12%)"

where that 'stock fstat' is the glibc translation of fstat into
fstatat() with an empty path, the 'patched fstat' is with this short
circuiting of the path lookup, and the 'real fstat' is the actual native
fstat() system call with none of this overhead.

Link: https://lore.kernel.org/lkml/20230903204858.lv7i3kqvw6eamhgz@f/Reported-by: Mateusz Guzik <mjguzik@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull ceph updates from Ilya Dryomov:
 "Mixed with some fixes and cleanups, this brings in reasonably complete
  fscrypt support to CephFS! The list of things which don't work with
  encryption should be fairly short, mostly around the edges: fallocate
  (not supported well in CephFS to begin with), copy_file_range
  (requires re-encryption), non-default striping patterns.

  This was a multi-year effort principally by Jeff Layton with
  assistance from Xiubo Li, Luís Henriques and others, including several
  dependant changes in the MDS, netfs helper library and fscrypt
  framework itself"

* tag 'ceph-for-6.6-rc1' of https://github.com/ceph/ceph-client: (53 commits)
  ceph: make num_fwd and num_retry to __u32
  ceph: make members in struct ceph_mds_request_args_ext a union
  rbd: use list_for_each_entry() helper
  libceph: do not include crypto/algapi.h
  ceph: switch ceph_lookup/atomic_open() to use new fscrypt helper
  ceph: fix updating i_truncate_pagecache_size for fscrypt
  ceph: wait for OSD requests' callbacks to finish when unmounting
  ceph: drop messages from MDS when unmounting
  ceph: update documentation regarding snapshot naming limitations
  ceph: prevent snapshot creation in encrypted locked directories
  ceph: add support for encrypted snapshot names
  ceph: invalidate pages when doing direct/sync writes
  ceph: plumb in decryption during reads
  ceph: add encryption support to writepage and writepages
  ceph: add read/modify/write to ceph_sync_write
  ceph: align data in pages in ceph_sync_write
  ceph: don't use special DIO path for encrypted inodes
  ceph: add truncate size handling support for fscrypt
  ceph: add object version support for sync read
  libceph: allow ceph_osdc_new_request to accept a multi-op read
  ...

Pull input updates from Dmitry Torokhov:

 - a new driver for Azoteq IQS7210A/7211A/E touch controllers

 - support for Azoteq IQS7222D variant added to iqs7222 driver

 - support for touch keys functionality added to Melfas MMS114 driver

 - new hardware IDs added to exc3000 and Goodix drivers

 - xpad driver gained support for GameSir T4 Kaleid Controller

 - a fix for xpad driver to properly support some third-party
   controllers that need a magic packet to start properly

 - a fix for psmouse driver to more reliably switch to RMI4 mode on
   devices that use native RMI4/SMbus protocol

 - a quirk for i8042 for TUXEDO Gemini 17 Gen1/Clevo PD70PN laptops

 - multiple drivers have been updated to make use of devm and other
   newer APIs such as dev_err_probe(), devm_regulator_get_enable(), and
   others.

* tag 'input-for-v6.6-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (83 commits)
  Input: goodix - add support for ACPI ID GDX9110
  Input: rpckbd - fix the return value handle for platform_get_irq()
  Input: tca6416-keypad - switch to using input core's polling features
  Input: tca6416-keypad - convert to use devm_* api
  Input: tca6416-keypad - fix interrupt enable disbalance
  Input: tca6416-keypad - rely on I2C core to set up suspend/resume
  Input: tca6416-keypad - always expect proper IRQ number in i2c client
  Input: lm8323 - convert to use devm_* api
  Input: lm8323 - rely on device core to create kp_disable attribute
  Input: qt2160 - convert to use devm_* api
  Input: qt2160 - do not hard code interrupt trigger
  Input: qt2160 - switch to using threaded interrupt handler
  Input: qt2160 - tweak check for i2c adapter functionality
  Input: psmouse - add delay when deactivating for SMBus mode
  Input: mcs-touchkey - fix uninitialized use of error in mcs_touchkey_probe()
  Input: qt1070 - convert to use devm_* api
  Input: mcs-touchkey - convert to use devm_* api
  Input: amikbd - convert to use devm_* api
  Input: lm8333 - convert to use devm_* api
  Input: mms114 - add support for touch keys
  ...

Pull watchdog updates from Wim Van Sebroeck:

 - add marvell GTI watchdog driver

 - add support for Amlogic-T7 SoCs

 - document the IPQ5018 watchdog compatible

 - enable COMPILE_TEST for more watchdog device drivers

 - core: stop watchdog when executing poweroff command

 - other small improvements and fixes

* tag 'linux-watchdog-6.6-rc1' of git://www.linux-watchdog.org/linux-watchdog: (21 commits)
  watchdog: Add support for Amlogic-T7 SoCs
  watchdog: Add a new struct for Amlogic-GXBB driver
  dt-bindings: watchdog: Add support for Amlogic-T7 SoCs
  dt-bindings: watchdog: qcom-wdt: document IPQ5018
  watchdog: imx2_wdt: Improve dev_crit() message
  watchdog: stm32: Drop unnecessary of_match_ptr()
  watchdog: sama5d4: readout initial state
  watchdog: intel-mid_wdt: add MODULE_ALIAS() to allow auto-load
  watchdog: core: stop watchdog when executing poweroff command
  watchdog: pm8916_wdt: Remove redundant of_match_ptr()
  watchdog: xilinx_wwdt: Use div_u64() in xilinx_wwdt_start()
  watchdog: starfive: Remove #ifdef guards for PM related functions
  watchdog: s3c2410: Fix potential deadlock on &wdt->lock
  watchdog:rit_wdt: Add support for WDIOF_CARDRESET
  dt-bindings: watchdog: ti,rti-wdt: Add support for WDIOF_CARDRESET
  watchdog: Enable COMPILE_TEST for more drivers
  watchdog: advantech_ec_wdt: fix Kconfig dependencies
  watchdog: Explicitly include correct DT includes
  Watchdog: Add marvell GTI watchdog driver
  dt-bindings: watchdog: marvell GTI system watchdog driver
  ...

Pull backlight updates from Lee Jones:
 "New Functionality:

   - Ensure correct includes are present and remove some that are not
     required

   - Drop redundant of_match_ptr() call to cast pointer to NULL

  Bug Fixes:

   - Revert to old (expected) behaviour of initialising PWM state on
     first brightness change

   - Correctly handle / propagate errors

   - Fix 'sometimes-uninitialised' issues"

* tag 'backlight-next-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: led_bl: Remove redundant of_match_ptr()
  backlight: lp855x: Drop ret variable in brightness change function
  backlight: gpio_backlight: Drop output GPIO direction check for initial power state
  backlight: lp855x: Catch errors when changing brightness
  backlight: lp855x: Initialize PWM state on first brightness change
  backlight: qcom-wled: Explicitly include correct DT includes

Pull gfs2 updates from Andreas Gruenbacher:

 - Fix a glock state (non-)transition bug when a dlm request times out
   and is canceled, and we have locking requests that can now be granted
   immediately

 - Various fixes and cleanups in how the logd and quotad daemons are
   woken up and terminated

 - Fix several bugs in the quota data reference counting and shrinking.
   Free quota data objects synchronously in put_super() instead of
   letting call_rcu() run wild

 - Make sure not to deallocate quota data during a withdraw; rather,
   defer quota data deallocation to put_super(). Withdraws can happen in
   contexts in which callers on the stack are holding quota data
   references

 - Many minor quota fixes and cleanups by Bob

 - Update the the mailing list address for gfs2 and dlm. (It's the same
   list for both and we are moving it to gfs2@lists.linux.dev)

 - Various other minor cleanups

* tag 'gfs2-v6.5-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: (51 commits)
  MAINTAINERS: Update dlm mailing list
  MAINTAINERS: Update gfs2 mailing list
  gfs2: change qd_slot_count to qd_slot_ref
  gfs2: check for no eligible quota changes
  gfs2: Remove useless assignment
  gfs2: simplify slot_get
  gfs2: Simplify qd2offset
  gfs2: introduce qd_bh_get_or_undo
  gfs2: Remove quota allocation info from quota file
  gfs2: use constant for array size
  gfs2: Set qd_sync_gen in do_sync
  gfs2: Remove useless err set
  gfs2: Small gfs2_quota_lock cleanup
  gfs2: move qdsb_put and reduce redundancy
  gfs2: improvements to sysfs status
  gfs2: Don't try to sync non-changes
  gfs2: Simplify function need_sync
  gfs2: remove unneeded pg_oflow variable
  gfs2: remove unneeded variable done
  gfs2: pass sdp to gfs2_write_buf_to_page
  ...

Pull fuse updates from Miklos Szeredi:

 - Revert non-waiting FLUSH due to a regression

 - Fix a lookup counter leak in readdirplus

 - Add an option to allow shared mmaps in no-cache mode

 - Add btime support and statx intrastructure to the protocol

 - Invalidate positive/negative dentry on failed create/delete

* tag 'fuse-update-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: conditionally fill kstat in fuse_do_statx()
  fuse: invalidate dentry on EEXIST creates or ENOENT deletes
  fuse: cache btime
  fuse: implement statx
  fuse: add ATTR_TIMEOUT macro
  fuse: add STATX request
  fuse: handle empty request_mask in statx
  fuse: write back dirty pages before direct write in direct_io_relax mode
  fuse: add a new fuse init flag to relax restrictions in no cache mode
  fuse: invalidate page cache pages before direct write
  fuse: nlookup missing decrement in fuse_direntplus_link
  Revert "fuse: in fuse_flush only wait if someone wants the return code"

Pull ata updates from Damien Le Moal:

 - Fix OF include file for ata platform drivers (Rob)

 - Simplify various ahci, sata and pata platform drivers using the
   function devm_platform_ioremap_resource() (Yangtao)

 - Cleanup libata time related argument types (e.g. timeouts values)
   (Sergey)

 - Cleanup libata code around error handling as all ata drivers now
   define a error_handler operation (Hannes and Niklas)

 - Remove functions intended for libsas that are in fact unused (Niklas)

 - Change the remove device callback of platform drivers to a null
   function (Uwe)

 - Simplify the pata_imx driver using devm_clk_get_enabled() (Li)

 - Remove old and uinused remnants of the ide code in arm, parisc,
   powerpc, sparc and m68k architectures and associated drivers
   (pata_buddha, pata_falcon and pata_gayle) (Geert)

 - Add missing MODULE_DESCRIPTION() in the sata_gemini and pata_ftide010
   drivers (me)

 - Several fixes for the pata_ep93xx and pata_falcon drivers (Nikita,
   Michael)

 - Add Elkhart Lake AHCI controller support to the ahci driver (Werner)

 - Disable NCQ trim on Micron 1100 drives (Pawel)

* tag 'ata-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata: (60 commits)
  ata: libata-core: Disable NCQ_TRIM on Micron 1100 drives
  ata: ahci: Add Elkhart Lake AHCI controller
  ata: pata_falcon: add data_swab option to byte-swap disk data
  ata: pata_falcon: fix IO base selection for Q40
  ata: pata_ep93xx: use soc_device_match for UDMA modes
  ata: pata_ep93xx: fix error return code in probe
  ata: sata_gemini: Add missing MODULE_DESCRIPTION
  ata: pata_ftide010: Add missing MODULE_DESCRIPTION
  m68k: Remove <asm/ide.h>
  ata: pata_gayle: Remove #include <asm/ide.h>
  ata: pata_falcon: Remove #include <asm/ide.h>
  ata: pata_buddha: Remove #include <asm/ide.h>
  asm-generic: Remove ide_iops.h
  sparc: Remove <asm/ide.h>
  powerpc: Remove <asm/ide.h>
  parisc: Remove <asm/ide.h>
  ARM: Remove <asm/ide.h>
  ata: pata_imx: Use helper function devm_clk_get_enabled()
  ata: sata_rcar: Convert to platform remove callback returning void
  ata: sata_mv: Convert to platform remove callback returning void
  ...

Pull mailbox updates from Jassi Brar:

 - qcom: fix incorrect num_chans counting

 - mhu: Remove redundant dev_err

 - bcm: fix comments

 - common changes:
    - convert to use devm_platform_get_and_ioremap_resource
    - correct DT includes

* tag 'mailbox-v6.6' of git://git.linaro.org/landing-teams/working/fujitsu/integration:
  mailbox: qcom-ipcc: fix incorrect num_chans counting
  mailbox: Explicitly include correct DT includes
  mailbox: ti-msgmgr: Use devm_platform_ioremap_resource_byname()
  mailbox: platform-mhu: Remove redundant dev_err()
  mailbox: bcm-pdc: Fix some kernel-doc comments
  mailbox: mailbox-test: Fix an error check in mbox_test_probe()
  mailbox: tegra-hsp: Convert to devm_platform_ioremap_resource()
  mailbox: rockchip: Use devm_platform_get_and_ioremap_resource()
  mailbox: mailbox-test: Use devm_platform_get_and_ioremap_resource()
  mailbox: bcm-pdc: Use devm_platform_get_and_ioremap_resource()
  mailbox: bcm-ferxrm-mailbox: Use devm_platform_get_and_ioremap_resource()

Merge tag 'mm-hotfixes-stable-2023-09-05-11-51' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "Seven hotfixes. Four are cc:stable and the remainder pertain to issues
  which were introduced in the current merge window"

* tag 'mm-hotfixes-stable-2023-09-05-11-51' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  sparc64: add missing initialization of folio in tlb_batch_add()
  mm: memory-failure: use rcu lock instead of tasklist_lock when collect_procs()
  revert "memfd: improve userspace warnings for missing exec-related flags".
  rcu: dump vmalloc memory info safely
  mm/vmalloc: add a safer version of find_vm_area() for debug
  tools/mm: fix undefined reference to pthread_once
  memcontrol: ensure memcg acquired by id is properly set up

Pull more tpm updates from Jarkko Sakkinen:
 "Two more bug fixes for tpm_crb, categorically disabling rng for AMD
  CPU's in the tpm_crb driver, discarding the earlier probing approach"

* tag 'tpmdd-v6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd:
  tpm: Enable hwrng only for Pluton on AMD CPUs
  tpm_crb: Fix an error handling path in crb_acpi_add()

Commit 1a10a44d ("sparc64: implement the new page table range API")
missed initialization of folio variable in tlb_batch_add() which causes
boot tests to crash.

Add missing initialization.

Link: https://lkml.kernel.org/r/20230904174350.GF3223@kernel.org
Fixes: 1a10a44d ("sparc64: implement the new page table range API")
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

We found a softlock issue in our test, analyzed the logs, and found that
the relevant CPU call trace as follows:

CPU0:
  _do_fork
    -> copy_process()
      -> write_lock_irq(&tasklist_lock)  //Disable irq,waiting for
      					 //tasklist_lock

CPU1:
  wp_page_copy()
    ->pte_offset_map_lock()
      -> spin_lock(&page->ptl);        //Hold page->ptl
    -> ptep_clear_flush()
      -> flush_tlb_others() ...
        -> smp_call_function_many()
          -> arch_send_call_function_ipi_mask()
            -> csd_lock_wait()         //Waiting for other CPUs respond
	                               //IPI

CPU2:
  collect_procs_anon()
    -> read_lock(&tasklist_lock)       //Hold tasklist_lock
      ->for_each_process(tsk)
        -> page_mapped_in_vma()
          -> page_vma_mapped_walk()
	    -> map_pte()
              ->spin_lock(&page->ptl)  //Waiting for page->ptl

We can see that CPU1 waiting for CPU0 respond IPI，CPU0 waiting for CPU2
unlock tasklist_lock, CPU2 waiting for CPU1 unlock page->ptl. As a result,
softlockup is triggered.

For collect_procs_anon(), what we're doing is task list iteration, during
the iteration, with the help of call_rcu(), the task_struct object is freed
only after one or more grace periods elapse. the logic as follows:

release_task()
  -> __exit_signal()
    -> __unhash_process()
      -> list_del_rcu()

  -> put_task_struct_rcu_user()
    -> call_rcu(&task->rcu, delayed_put_task_struct)

delayed_put_task_struct()
  -> put_task_struct()
  -> if (refcount_sub_and_test())
     	__put_task_struct()
          -> free_task()

Therefore, under the protection of the rcu lock, we can safely use
get_task_struct() to ensure a safe reference to task_struct during the
iteration.

By removing the use of tasklist_lock in task list iteration, we can break
the softlock chain above.

The same logic can also be applied to:
 - collect_procs_file()
 - collect_procs_fsdax()
 - collect_procs_ksm()

Link: https://lkml.kernel.org/r/20230828022527.241693-1-tongtiangen@huawei.comSigned-off-by: Tong Tiangen <tongtiangen@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

This warning is telling userspace developers to pass MFD_EXEC and
MFD_NOEXEC_SEAL to memfd_create().  Commit 434ed335 ("memfd: improve
userspace warnings for missing exec-related flags") made the warning more
frequent and visible in the hope that this would accelerate the fixing of
errant userspace.

But the overall effect is to generate far too much dmesg noise.

Fixes: 434ed335 ("memfd: improve userspace warnings for missing exec-related flags")
Reported-by: Damian Tometzki <dtometzki@fedoraproject.org>
Closes: https://lkml.kernel.org/r/ZPFzCSIgZ4QuHsSC@fedora.fritz.box
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Daniel Verkamp <dverkamp@chromium.org>
Cc: Jeff Xu <jeffxu@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Pull Kbuild updates from Masahiro Yamada:

 - Enable -Wenum-conversion warning option

 - Refactor the rpm-pkg target

 - Fix scripts/setlocalversion to consider annotated tags for rt-kernel

 - Add a jump key feature for the search menu of 'make nconfig'

 - Support Qt6 for 'make xconfig'

 - Enable -Wformat-overflow, -Wformat-truncation, -Wstringop-overflow,
   and -Wrestrict warnings for W=1 builds

 - Replace <asm/export.h> with <linux/export.h> for alpha, ia64, and
   sparc

 - Support DEB_BUILD_OPTIONS=parallel=N for the debian source package

 - Refactor scripts/Makefile.modinst and fix some modules_sign issues

 - Add a new Kconfig env variable to warn symbols that are not defined
   anywhere

 - Show help messages of config fragments in 'make help'

* tag 'kbuild-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (62 commits)
  kconfig: fix possible buffer overflow
  kbuild: Show marked Kconfig fragments in "help"
  kconfig: add warn-unknown-symbols sanity check
  kbuild: dummy-tools: make MPROFILE_KERNEL checks work on BE
  Documentation/llvm: refresh docs
  modpost: Skip .llvm.call-graph-profile section check
  kbuild: support modules_sign for external modules as well
  kbuild: support 'make modules_sign' with CONFIG_MODULE_SIG_ALL=n
  kbuild: move more module installation code to scripts/Makefile.modinst
  kbuild: reduce the number of mkdir calls during modules_install
  kbuild: remove $(MODLIB)/source symlink
  kbuild: move depmod rule to scripts/Makefile.modinst
  kbuild: add modules_sign to no-{compiler,sync-config}-targets
  kbuild: do not run depmod for 'make modules_sign'
  kbuild: deb-pkg: support DEB_BUILD_OPTIONS=parallel=N in debian/rules
  alpha: remove <asm/export.h>
  alpha: replace #include <asm/export.h> with #include <linux/export.h>
  ia64: remove <asm/export.h>
  ia64: replace #include <asm/export.h> with #include <linux/export.h>
  sparc: remove <asm/export.h>
  ...

Pull more MM updates from Andrew Morton:

 - Stefan Roesch has added ksm statistics to /proc/pid/smaps

 - Also a number of singleton patches, mainly cleanups and leftovers

* tag 'mm-stable-2023-09-04-14-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  mm/kmemleak: move up cond_resched() call in page scanning loop
  mm: page_alloc: remove stale CMA guard code
  MAINTAINERS: add rmap.h to mm entry
  rmap: remove anon_vma_link() nommu stub
  proc/ksm: add ksm stats to /proc/pid/smaps
  mm/hwpoison: rename hwp_walk* to hwpoison_walk*
  mm: memory-failure: add PageOffline() check

Pull microblaze updates from Michal Simek:

 - Cleanup DT headers

 - Remove unused zalloc_maybe_bootmem()

 - Make virt_to_pfn() a static inline

* tag 'microblaze-v6.6' of git://git.monstr.eu/linux-2.6-microblaze:
  microblaze: Make virt_to_pfn() a static inline
  microblaze: Remove zalloc_maybe_bootmem()
  microblaze: Explicitly include correct DT includes

Currently, for double invoke call_rcu(), will dump rcu_head objects memory
info, if the objects is not allocated from the slab allocator, the
vmalloc_dump_obj() will be invoke and the vmap_area_lock spinlock need to
be held, since the call_rcu() can be invoked in interrupt context,
therefore, there is a possibility of spinlock deadlock scenarios.

And in Preempt-RT kernel, the rcutorture test also trigger the following
lockdep warning:

BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0
preempt_count: 1, expected: 0
RCU nest depth: 1, expected: 1
3 locks held by swapper/0/1:
 #0: ffffffffb534ee80 (fullstop_mutex){+.+.}-{4:4}, at: torture_init_begin+0x24/0xa0
 #1: ffffffffb5307940 (rcu_read_lock){....}-{1:3}, at: rcu_torture_init+0x1ec7/0x2370
 #2: ffffffffb536af40 (vmap_area_lock){+.+.}-{3:3}, at: find_vmap_area+0x1f/0x70
irq event stamp: 565512
hardirqs last  enabled at (565511): [<ffffffffb379b138>] __call_rcu_common+0x218/0x940
hardirqs last disabled at (565512): [<ffffffffb5804262>] rcu_torture_init+0x20b2/0x2370
softirqs last  enabled at (399112): [<ffffffffb36b2586>] __local_bh_enable_ip+0x126/0x170
softirqs last disabled at (399106): [<ffffffffb43fef59>] inet_register_protosw+0x9/0x1d0
Preemption disabled at:
[<ffffffffb58040c3>] rcu_torture_init+0x1f13/0x2370
CPU: 0 PID: 1 Comm: swapper/0 Tainted: G        W          6.5.0-rc4-rt2-yocto-preempt-rt+ #15
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x68/0xb0
 dump_stack+0x14/0x20
 __might_resched+0x1aa/0x280
 ? __pfx_rcu_torture_err_cb+0x10/0x10
 rt_spin_lock+0x53/0x130
 ? find_vmap_area+0x1f/0x70
 find_vmap_area+0x1f/0x70
 vmalloc_dump_obj+0x20/0x60
 mem_dump_obj+0x22/0x90
 __call_rcu_common+0x5bf/0x940
 ? debug_smp_processor_id+0x1b/0x30
 call_rcu_hurry+0x14/0x20
 rcu_torture_init+0x1f82/0x2370
 ? __pfx_rcu_torture_leak_cb+0x10/0x10
 ? __pfx_rcu_torture_leak_cb+0x10/0x10
 ? __pfx_rcu_torture_init+0x10/0x10
 do_one_initcall+0x6c/0x300
 ? debug_smp_processor_id+0x1b/0x30
 kernel_init_freeable+0x2b9/0x540
 ? __pfx_kernel_init+0x10/0x10
 kernel_init+0x1f/0x150
 ret_from_fork+0x40/0x50
 ? __pfx_kernel_init+0x10/0x10
 ret_from_fork_asm+0x1b/0x30
 </TASK>

The previous patch fixes this by using the deadlock-safe best-effort
version of find_vm_area.  However, in case of failure print the fact that
the pointer was a vmalloc pointer so that we print at least something.

Link: https://lkml.kernel.org/r/20230904180806.1002832-2-joel@joelfernandes.org
Fixes: 98f18083 ("mm: Make mem_dump_obj() handle vmalloc() memory")
Signed-off-by: Zqiang <qiang.zhang1211@gmail.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Reported-by: Zhen Lei <thunder.leizhen@huaweicloud.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

It is unsafe to dump vmalloc area information when trying to do so from
some contexts.  Add a safer trylock version of the same function to do a
best-effort VMA finding and use it from vmalloc_dump_obj().

[applied test robot feedback on unused function fix.]
[applied Uladzislau feedback on locking.]
Link: https://lkml.kernel.org/r/20230904180806.1002832-1-joel@joelfernandes.org
Fixes: 98f18083 ("mm: Make mem_dump_obj() handle vmalloc() memory")
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reported-by: Zhen Lei <thunder.leizhen@huaweicloud.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Zqiang <qiang.zhang1211@gmail.com>
Cc: <stable@vger.kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Commit 97d5f2e9 ("tools api fs: More thread safety for global
filesystem variables") introduces pthread_once, so the libpthread
should be added at link time, or we'll meet the following compile
error when 'make -C tools/mm':

  gcc -Wall -Wextra -I../lib/ -o page-types page-types.c ../lib/api/libapi.a
  ~/linux/tools/lib/api/fs/fs.c:146: undefined reference to `pthread_once'
  ~/linux/tools/lib/api/fs/fs.c:147: undefined reference to `pthread_once'
  ~/linux/tools/lib/api/fs/fs.c:148: undefined reference to `pthread_once'
  ~/linux/tools/lib/api/fs/fs.c:149: undefined reference to `pthread_once'
  ~/linux/tools/lib/api/fs/fs.c:150: undefined reference to `pthread_once'
  /usr/bin/ld: ../lib/api/libapi.a(libapi-in.o):~/linux/tools/lib/api/fs/fs.c:151:
  more undefined references to `pthread_once' follow
  collect2: error: ld returned 1 exit status
  make: *** [Makefile:22: page-types] Error 1

Link: https://lkml.kernel.org/r/20230831034205.2376653-1-xiexiuqi@huaweicloud.com
Fixes: 97d5f2e9 ("tools api fs: More thread safety for global filesystem variables")
Signed-off-by: Xie XiuQi <xiexiuqi@huawei.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

In the eviction recency check, we attempt to retrieve the memcg to which
the folio belonged when it was evicted, by the memcg id stored in the
shadow entry.  However, there is a chance that the retrieved memcg is not
the original memcg that has been killed, but a new one which happens to
have the same id.

This is a somewhat unfortunate, but acceptable and rare inaccuracy in the
heuristics.  However, if we retrieve this new memcg between its allocation
and when it is properly attached to the memcg hierarchy, we could run into
the following NULL pointer exception during the memcg hierarchy traversal
done in mem_cgroup_get_nr_swap_pages():

[ 155757.793456] BUG: kernel NULL pointer dereference, address: 00000000000000c0
[ 155757.807568] #PF: supervisor read access in kernel mode
[ 155757.818024] #PF: error_code(0x0000) - not-present page
[ 155757.828482] PGD 401f77067 P4D 401f77067 PUD 401f76067 PMD 0
[ 155757.839985] Oops: 0000 [#1] SMP
[ 155757.887870] RIP: 0010:mem_cgroup_get_nr_swap_pages+0x3d/0xb0
[ 155757.899377] Code: 29 19 4a 02 48 39 f9 74 63 48 8b 97 c0 00 00 00 48 8b b7 58 02 00 00 48 2b b7 c0 01 00 00 48 39 f0 48 0f 4d c6 48 39 d1 74 42 <48> 8b b2 c0 00 00 00 48 8b ba 58 02 00 00 48 2b ba c0 01 00 00 48
[ 155757.937125] RSP: 0018:ffffc9002ecdfbc8 EFLAGS: 00010286
[ 155757.947755] RAX: 00000000003a3b1c RBX: 000007ffffffffff RCX: ffff888280183000
[ 155757.962202] RDX: 0000000000000000 RSI: 0007ffffffffffff RDI: ffff888bbc2d1000
[ 155757.976648] RBP: 0000000000000001 R08: 000000000000000b R09: ffff888ad9cedba0
[ 155757.991094] R10: ffffea0039c07900 R11: 0000000000000010 R12: ffff888b23a7b000
[ 155758.005540] R13: 0000000000000000 R14: ffff888bbc2d1000 R15: 000007ffffc71354
[ 155758.019991] FS:  00007f6234c68640(0000) GS:ffff88903f9c0000(0000) knlGS:0000000000000000
[ 155758.036356] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 155758.048023] CR2: 00000000000000c0 CR3: 0000000a83eb8004 CR4: 00000000007706e0
[ 155758.062473] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 155758.076924] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 155758.091376] PKRU: 55555554
[ 155758.096957] Call Trace:
[ 155758.102016]  <TASK>
[ 155758.106502]  ? __die+0x78/0xc0
[ 155758.112793]  ? page_fault_oops+0x286/0x380
[ 155758.121175]  ? exc_page_fault+0x5d/0x110
[ 155758.129209]  ? asm_exc_page_fault+0x22/0x30
[ 155758.137763]  ? mem_cgroup_get_nr_swap_pages+0x3d/0xb0
[ 155758.148060]  workingset_test_recent+0xda/0x1b0
[ 155758.157133]  workingset_refault+0xca/0x1e0
[ 155758.165508]  filemap_add_folio+0x4d/0x70
[ 155758.173538]  page_cache_ra_unbounded+0xed/0x190
[ 155758.182919]  page_cache_sync_ra+0xd6/0x1e0
[ 155758.191738]  filemap_read+0x68d/0xdf0
[ 155758.199495]  ? mlx5e_napi_poll+0x123/0x940
[ 155758.207981]  ? __napi_schedule+0x55/0x90
[ 155758.216095]  __x64_sys_pread64+0x1d6/0x2c0
[ 155758.224601]  do_syscall_64+0x3d/0x80
[ 155758.232058]  entry_SYSCALL_64_after_hwframe+0x46/0xb0
[ 155758.242473] RIP: 0033:0x7f62c29153b5
[ 155758.249938] Code: e8 48 89 75 f0 89 7d f8 48 89 4d e0 e8 b4 e6 f7 ff 41 89 c0 4c 8b 55 e0 48 8b 55 e8 48 8b 75 f0 8b 7d f8 b8 11 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 33 44 89 c7 48 89 45 f8 e8 e7 e6 f7 ff 48 8b
[ 155758.288005] RSP: 002b:00007f6234c5ffd0 EFLAGS: 00000293 ORIG_RAX: 0000000000000011
[ 155758.303474] RAX: ffffffffffffffda RBX: 00007f628c4e70c0 RCX: 00007f62c29153b5
[ 155758.318075] RDX: 000000000003c041 RSI: 00007f61d2986000 RDI: 0000000000000076
[ 155758.332678] RBP: 00007f6234c5fff0 R08: 0000000000000000 R09: 0000000064d5230c
[ 155758.347452] R10: 000000000027d450 R11: 0000000000000293 R12: 000000000003c041
[ 155758.362044] R13: 00007f61d2986000 R14: 00007f629e11b060 R15: 000000000027d450
[ 155758.376661]  </TASK>

This patch fixes the issue by moving the memcg's id publication from the
alloc stage to online stage, ensuring that any memcg acquired via id must
be connected to the memcg tree.

Link: https://lkml.kernel.org/r/20230823225430.166925-1-nphamcs@gmail.com
Fixes: f78dfc7b ("workingset: fix confusion around eviction vs refault container")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Co-developed-by: Nhat Pham <nphamcs@gmail.com>
Signed-off-by: Nhat Pham <nphamcs@gmail.com>
Acked-by: Shakeel Butt <shakeelb@google.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Pull OpenRISC updates from Stafford Horne:

 - Fixes from me to cleanup all compiler warnings reported under
   arch/openrisc

 - One cleanup from Linus Walleij to convert pfn macros to static
   inlines

* tag 'for-linus' of https://github.com/openrisc/linux:
  openrisc: Remove kernel-doc marker from ioremap comment
  openrisc: Remove unused tlb_init function
  openriac: Remove unused nommu_dump_state function
  openrisc: Include cpu.h and switch_to.h for prototypes
  openrisc: Add prototype for die to bug.h
  openrisc: Add prototype for show_registers to processor.h
  openrisc: Declare do_signal function as static
  openrisc: Add missing prototypes for assembly called fnctions
  openrisc: Make pfn accessors statics inlines

Buffer 'new_argv' is accessed without bound check after accessing with
bound check via 'new_argc' index.

Fixes: e298f3b4 ("kconfig: add built-in function support")
Co-developed-by: Ivanov Mikhail <ivanov.mikhail1@huawei-partners.com>
Signed-off-by: Konstantin Meskhidze <konstantin.meskhidze@huawei.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

The new gfs2@ list will also be used for dlm development.
Signed-off-by: Andrew Price <anprice@redhat.com>
Acked-by: David Teigland <teigland@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Signed-off-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Breaking out early when a match is found leads to an incorrect num_chans
value when more than one ipcc mailbox channel is used by the same device.

Fixes: e9d50e4b ("mailbox: qcom-ipcc: Dynamic alloc for channel arrangement")
Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Convert platform_get_resource_byname() + devm_ioremap_resource() to a
single call to devm_platform_ioremap_resource_byname(), as this is
exactly what this function does.
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

There is no need to call the dev_err() function directly to print a custom
message when handling an error from platform_get_irq() function as
it is going to display an appropriate error message in case of a failure.
Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Fix some kernel-doc comments to silence the warnings:

drivers/mailbox/bcm-pdc-mailbox.c:707: warning: Function parameter or member 'pdcs' not described in 'pdc_tx_list_sg_add'
drivers/mailbox/bcm-pdc-mailbox.c:707: warning: Excess function parameter 'spu_idx' description in 'pdc_tx_list_sg_add'
drivers/mailbox/bcm-pdc-mailbox.c:875: warning: Function parameter or member 'pdcs' not described in 'pdc_rx_list_sg_add'
drivers/mailbox/bcm-pdc-mailbox.c:875: warning: Excess function parameter 'spu_idx' description in 'pdc_rx_list_sg_add'
drivers/mailbox/bcm-pdc-mailbox.c:966: warning: Function parameter or member 't' not described in 'pdc_tasklet_cb'
drivers/mailbox/bcm-pdc-mailbox.c:966: warning: Excess function parameter 'data' description in 'pdc_tasklet_cb'
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

mbox_test_request_channel() function returns NULL or
error value embedded in the pointer (PTR_ERR).
Evaluate the return value using IS_ERR_OR_NULL.
Signed-off-by: Minjie Du <duminjie@vivo.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Use devm_platform_ioremap_resource() to simplify code.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Convert platform_get_resource(), devm_ioremap_resource() to a single
call to devm_platform_get_and_ioremap_resource(), as this is exactly
what this function does.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Convert platform_get_resource(), devm_ioremap_resource() to a single
call to devm_platform_get_and_ioremap_resource(), as this is exactly
what this function does.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Convert platform_get_resource(), devm_ioremap_resource() to a single
call to devm_platform_get_and_ioremap_resource(), as this is exactly
what this function does.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Convert platform_get_resource(), devm_ioremap_resource() to a single
call to devm_platform_get_and_ioremap_resource(), as this is exactly
what this function does.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Variable qd_slot_count is a reference count, not a count of slots. This
patch renames it to qd_slot_ref to make that more clear.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Before this patch, function gfs2_quota_sync would always allocate a page
full of memory and increment its quota sync generation number. This
happened even when the system was completely idle or if no blocks were
allocated or quota changes made. This patch adds function qd_changed
to determine if any changes have been made that qualify for a
quota sync. If not, it avoids the memory allocation and bumping the
generation number, along with all the additional work it would do.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

This assignment is unnecessary because if error was not already 0, it
would have branched to an error label already.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Simplify function slot_get and get rid of the goto that jumps into the
middle of an else branch.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>