Use a more comprehensible() max instead of hand coding it with ifs in
io_sqd_update_thread_idle().
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

io_uring manipulates references twice for each request, and hence is very
sensitive to performance of the reference count. This commit borrows a
trick from:

commit f958d7b5
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Thu Apr 11 10:06:20 2019 -0700

    mm: make page ref count overflow check tighter and more explicit

and switches to atomic_t for references, while still retaining overflow
and underflow checks.

This is good for a 2-3% increase in peak IOPS on a single core. Before:

IOPS=2970879, IOS/call=31/31, inflight=128 (128)
IOPS=2952597, IOS/call=31/31, inflight=128 (128)
IOPS=2943904, IOS/call=31/31, inflight=128 (128)
IOPS=2930006, IOS/call=31/31, inflight=96 (96)

and after:

IOPS=3054354, IOS/call=31/31, inflight=128 (128)
IOPS=3059038, IOS/call=31/31, inflight=128 (128)
IOPS=3060320, IOS/call=31/31, inflight=128 (128)
IOPS=3068256, IOS/call=31/31, inflight=96 (96)
Signed-off-by: Jens Axboe <axboe@kernel.dk>

No functional changes in this patch, just in preparation for handling the
references a bit more efficiently.
Signed-off-by: Jens Axboe <axboe@kernel.dk>

If not for async_data NULL check, io_resubmit_prep() is already an rw
specific version of io_req_prep_async(), but slower because 1) it always
goes through io_import_iovec() even if following io_setup_async_rw() the
result 2) instead of initialising iovec/iter in-place it does it
on-stack and then copies with io_setup_async_rw().
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Merge two function and do renaming in favour of the second one, it
relays the meaning better.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

needs_async_data controls allocation of async_data, and used in two
cases. 1) when async setup requires it (by io_req_prep_async() or
handler themselves), and 2) when op always needs additional space to
operate, like timeouts do.

Opcode preps already don't bother about the second case and do
allocation unconditionally, restrict needs_async_data to the first case
only and rename it into needs_async_setup.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
[axboe: update for IOPOLL fix]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

All opcode handlers pretty well know whether they need async data or
not, and can skip testing for needs_async_data. The exception is rw
the generic path, but those test the flag by hand anyway. So, check the
flag and make io_alloc_async_data() allocating unconditionally.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

IORING_OP_[SEND,RECV] don't need async setup neither will get into
io_req_prep_async(). Remove them from io_req_prep_async() and remove
needs_async_data checks from the related setup functions.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

__io_cqring_fill_event() takes cflags as long to squeeze it into u32 in
an CQE, awhile all users pass int or unsigned. Replace it with unsigned
int and store it as u32 in struct io_completion to match CQE.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Always complete request holding the mutex instead of doing that strange
dancing with conditional ordering.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Add a simple helper doing CQE posting, marking request for link-failure,
and putting both submission and completion references.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

io_fixed_file_slot() and io_file_from_index() behave pretty similarly,
DRY and call one from another.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Use io_req_task_queue_fail() on the fail path of io_req_task_queue().
It's unlikely to happen, so don't care about additional overhead, but
allows to keep all the req->result invariant in a single function.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Don't bother to take a ctx->refs for io_req_task_cancel() because it
take uring_lock before putting a request, and the context is promised to
stay alive until unlock happens.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull btrfs fix from David Sterba:
 "One more patch that we'd like to get to 5.12 before release.

  It's changing where and how the superblock is stored in the zoned
  mode. It is an on-disk format change but so far there are no
  implications for users as the proper mkfs support hasn't been merged
  and is waiting for the kernel side to settle.

  Until now, the superblocks were derived from the zone index, but zone
  size can differ per device. This is changed to be based on fixed
  offset values, to make it independent of the device zone size.

  The work on that got a bit delayed, we discussed the exact locations
  to support potential device sizes and usecases. (Partially delayed
  also due to my vacation.) Having that in the same release where the
  zoned mode is declared usable is highly desired, there are userspace
  projects that need to be updated to recognize the feature. Pushing
  that to the next release would make things harder to test"

* tag 'for-5.12-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: zoned: move superblock logging zone location

Pull locking fixlets from Ingo Molnar:
 "Two minor fixes: one for a Clang warning, the other improves an
  ambiguous/confusing kernel log message"

* tag 'locking-urgent-2021-04-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lockdep: Address clang -Wformat warning printing for %hd
  lockdep: Add a missing initialization hint to the "INFO: Trying to register non-static key" message

Pull x86 fixes from Borislav Petkov:

 - Fix the vDSO exception handling return path to disable interrupts
   again.

 - A fix for the CE collector to return the proper return values to its
   callers which are used to convey what the collector has done with the
   error address.

* tag 'x86_urgent_for_v5.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/traps: Correct exc_general_protection() and math_error() return paths
  RAS/CEC: Correct ce_add_elem()'s returned values

Pull percpu fix from Dennis Zhou:
 "This contains a fix for sporadically failing atomic percpu
  allocations.

  I only caught it recently while I was reviewing a new series [1] and
  simultaneously saw reports by btrfs in xfstests [2] and [3].

  In v5.9, memcg accounting was extended to percpu done by adding a
  second type of chunk. I missed an interaction with the free page float
  count used to ensure we can support atomic allocations. If one type of
  chunk has no free pages, but the other has enough to satisfy the free
  page float requirement, we will not repopulate the free pages for the
  former type of chunk. This led to the sporadically failing atomic
  allocations"

Link: https://lore.kernel.org/linux-mm/20210324190626.564297-1-guro@fb.com/ [1]
Link: https://lore.kernel.org/linux-mm/20210401185158.3275.409509F4@e16-tech.com/ [2]
Link: https://lore.kernel.org/linux-mm/CAL3q7H5RNBjCi708GH7jnczAOe0BLnacT9C+OBgA-Dx9jhB6SQ@mail.gmail.com/ [3]

* 'for-5.12-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu:
  percpu: make pcpu_nr_empty_pop_pages per chunk type

Pull SCSI fixes from James Bottomley:
 "Seven fixes, all in drivers.

  The hpsa three are the most extensive and the most problematic: it's a
  packed structure misalignment that oopses on ia64 but looks like it
  would also oops on quite a few non-x86 architectures.

  The pm80xx is a regression and the rest are bug fixes for patches in
  the misc tree"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: scsi_transport_srp: Don't block target in SRP_PORT_LOST state
  scsi: target: iscsi: Fix zero tag inside a trace event
  scsi: pm80xx: Fix chip initialization failure
  scsi: ufs: core: Fix wrong Task Tag used in task management request UPIUs
  scsi: ufs: core: Fix task management request completion timeout
  scsi: hpsa: Add an assert to prevent __packed reintroduction
  scsi: hpsa: Fix boot on ia64 (atomic_t alignment)
  scsi: hpsa: Use __packed on individual structs, not header-wide

Pull powerpc fixes from Michael Ellerman:
 "Some some more powerpc fixes for 5.12:

   - Fix an oops triggered by ptrace when CONFIG_PPC_FPU_REGS=n

   - Fix an oops on sigreturn when the VDSO is unmapped on 32-bit

   - Fix vdso_wrapper.o not being rebuilt everytime vdso.so is rebuilt

  Thanks to Christophe Leroy"

* tag 'powerpc-5.12-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/vdso: Make sure vdso_wrapper.o is rebuilt everytime vdso.so is rebuilt
  powerpc/signal32: Fix Oops on sigreturn with unmapped VDSO
  powerpc/ptrace: Don't return error when getting/setting FP regs without CONFIG_PPC_FPU_REGS

Merge tag 'driver-core-5.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fix from Greg KH:
 "Here is a single driver core fix for 5.12-rc7 to resolve a reported
  problem that caused some devices to lockup when booting. It has been
  in linux-next with no reported issues"

* tag 'driver-core-5.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  driver core: Fix locking bug in deferred_probe_timeout_work_func()

Pull USB/Thunderbolt fixes from Greg KH:
 "Here are a few small USB and Thunderbolt driver fixes for 5.12-rc7 for
  reported issues:

   - thunderbolt leaks and off-by-one fix

   - cdnsp deque fix

   - usbip fixes for syzbot-reported issues

  All have been in linux-next with no reported problems"

* tag 'usb-5.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usbip: synchronize event handler with sysfs code paths
  usbip: vudc synchronize sysfs code paths
  usbip: stub-dev synchronize sysfs code paths
  usbip: add sysfs_lock to synchronize sysfs code paths
  thunderbolt: Fix off by one in tb_port_find_retimer()
  thunderbolt: Fix a leak in tb_retimer_add()
  usb: cdnsp: Fixes issue with dequeuing requests after disabling endpoint

Pull i2c fixes from Wolfram Sang:
 "A mixture of driver and documentation bugfixes for I2C"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: imx: mention Oleksij as maintainer of the binding docs
  i2c: exynos5: correct top kerneldoc
  i2c: designware: Adjust bus_freq_hz when refuse high speed mode set
  i2c: hix5hd2: use the correct HiSilicon copyright
  i2c: gpio: update email address in binding docs
  i2c: imx: drop me as maintainer of binding docs
  i2c: stm32f4: Mundane typo fix
  I2C: JZ4780: Fix bug for Ingenic X1000.
  i2c: turn recovery error on init to debug

Moves the location of the superblock logging zones. The new locations of
the logging zones are now determined based on fixed block addresses
instead of on fixed zone numbers.

The old placement method based on fixed zone numbers causes problems when
one needs to inspect a file system image without access to the drive zone
information. In such case, the super block locations cannot be reliably
determined as the zone size is unknown. By locating the superblock logging
zones using fixed addresses, we can scan a dumped file system image without
the zone information since a super block copy will always be present at or
after the fixed known locations.

Introduce the following three pairs of zones containing fixed offset
locations, regardless of the device zone size.

  - primary superblock: offset   0B (and the following zone)
  - first copy:         offset 512G (and the following zone)
  - Second copy:        offset   4T (4096G, and the following zone)

If a logging zone is outside of the disk capacity, we do not record the
superblock copy.

The first copy position is much larger than for a non-zoned filesystem,
which is at 64M.  This is to avoid overlapping with the log zones for
the primary superblock. This higher location is arbitrary but allows
supporting devices with very large zone sizes, plus some space around in
between.

Such large zone size is unrealistic and very unlikely to ever be seen in
real devices. Currently, SMR disks have a zone size of 256MB, and we are
expecting ZNS drives to be in the 1-4GB range, so this limit gives us
room to breathe. For now, we only allow zone sizes up to 8GB. The
maximum zone size that would still fit in the space is 256G.

The fixed location addresses are somewhat arbitrary, with the intent of
maintaining superblock reliability for smaller and larger devices, with
the preference for the latter. For this reason, there are two superblocks
under the first 1T. This should cover use cases for physical devices and
for emulated/device-mapper devices.

The superblock logging zones are reserved for superblock logging and
never used for data or metadata blocks. Note that we only reserve the
two zones per primary/copy actually used for superblock logging. We do
not reserve the ranges of zones possibly containing superblocks with the
largest supported zone size (0-16GB, 512G-528GB, 4096G-4112G).

The zones containing the fixed location offsets used to store
superblocks on a non-zoned volume are also reserved to avoid confusion.
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Pull clk fixes from Stephen Boyd:
 "Here's the latest pile of clk driver and clk framework fixes for this
  release:

   - Two clk framework fixes for a long standing issue in
     clk_notifier_{register,unregister}() where we used a pointer that
     was for a struct containing a list head when there was no container
     struct

   - A compile warning fix for socfpga that's good to have

   - A double free problem with devm registered fixed factor clks

   - One last fix to the Qualcomm camera clk driver to use the right clk
     ops so clks don't get stuck and stop working because the firmware
     takes them for a ride"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: fixed: fix double free in resource managed fixed-factor clock
  clk: fix invalid usage of list cursor in unregister
  clk: fix invalid usage of list cursor in register
  clk: qcom: camcc: Update the clock ops for the SC7180
  clk: socfpga: fix iomem pointer cast on 64-bit

Merge tag 'perf-tools-fixes-for-v5.12-2020-04-09' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

Pull perf tool fixes from Arnaldo Carvalho de Melo:

 - Fix wrong LBR block sorting in 'perf report'

 - Fix 'perf inject' repipe usage when consuming perf.data files

 - Avoid potential buffer overrun when decoding ARM SPE hardware tracing
   packets, bug found using a fuzzer

* tag 'perf-tools-fixes-for-v5.12-2020-04-09' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
  perf arm-spe: Avoid potential buffer overrun
  perf report: Fix wrong LBR block sorting
  perf inject: Fix repipe usage

Merge misc fixes from Andrew Morton:
 "14 patches.

  Subsystems affected by this patch series: mm (kasan, gup, pagecache,
  and kfence), MAINTAINERS, mailmap, nds32, gcov, ocfs2, ia64, and lib"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  lib: fix kconfig dependency on ARCH_WANT_FRAME_POINTERS
  kfence, x86: fix preemptible warning on KPTI-enabled systems
  lib/test_kasan_module.c: suppress unused var warning
  kasan: fix conflict with page poisoning
  fs: direct-io: fix missing sdio->boundary
  ia64: fix user_stack_pointer() for ptrace()
  ocfs2: fix deadlock between setattr and dio_end_io_write
  gcov: re-fix clang-11+ support
  nds32: flush_dcache_page: use page_mapping_file to avoid races with swapoff
  mm/gup: check page posion status for coredump.
  .mailmap: fix old email addresses
  mailmap: update email address for Jordan Crouse
  treewide: change my e-mail address, fix my name
  MAINTAINERS: update CZ.NIC's Turris information

Pull networking fixes from Jakub Kicinski:
 "Networking fixes for 5.12-rc7, including fixes from can, ipsec,
  mac80211, wireless, and bpf trees.

  No scary regressions here or in the works, but small fixes for 5.12
  changes keep coming.

  Current release - regressions:

   - virtio: do not pull payload in skb->head

   - virtio: ensure mac header is set in virtio_net_hdr_to_skb()

   - Revert "net: correct sk_acceptq_is_full()"

   - mptcp: revert "mptcp: provide subflow aware release function"

   - ethernet: lan743x: fix ethernet frame cutoff issue

   - dsa: fix type was not set for devlink port

   - ethtool: remove link_mode param and derive link params from driver

   - sched: htb: fix null pointer dereference on a null new_q

   - wireless: iwlwifi: Fix softirq/hardirq disabling in
     iwl_pcie_enqueue_hcmd()

   - wireless: iwlwifi: fw: fix notification wait locking

   - wireless: brcmfmac: p2p: Fix deadlock introduced by avoiding the
     rtnl dependency

  Current release - new code bugs:

   - napi: fix hangup on napi_disable for threaded napi

   - bpf: take module reference for trampoline in module

   - wireless: mt76: mt7921: fix airtime reporting and related tx hangs

   - wireless: iwlwifi: mvm: rfi: don't lock mvm->mutex when sending
     config command

  Previous releases - regressions:

   - rfkill: revert back to old userspace API by default

   - nfc: fix infinite loop, refcount & memory leaks in LLCP sockets

   - let skb_orphan_partial wake-up waiters

   - xfrm/compat: Cleanup WARN()s that can be user-triggered

   - vxlan, geneve: do not modify the shared tunnel info when PMTU
     triggers an ICMP reply

   - can: fix msg_namelen values depending on CAN_REQUIRED_SIZE

   - can: uapi: mark union inside struct can_frame packed

   - sched: cls: fix action overwrite reference counting

   - sched: cls: fix err handler in tcf_action_init()

   - ethernet: mlxsw: fix ECN marking in tunnel decapsulation

   - ethernet: nfp: Fix a use after free in nfp_bpf_ctrl_msg_rx

   - ethernet: i40e: fix receiving of single packets in xsk zero-copy
     mode

   - ethernet: cxgb4: avoid collecting SGE_QBASE regs during traffic

  Previous releases - always broken:

   - bpf: Refuse non-O_RDWR flags in BPF_OBJ_GET

   - bpf: Refcount task stack in bpf_get_task_stack

   - bpf, x86: Validate computation of branch displacements

   - ieee802154: fix many similar syzbot-found bugs
       - fix NULL dereferences in netlink attribute handling
       - reject unsupported operations on monitor interfaces
       - fix error handling in llsec_key_alloc()

   - xfrm: make ipv4 pmtu check honor ip header df

   - xfrm: make hash generation lock per network namespace

   - xfrm: esp: delete NETIF_F_SCTP_CRC bit from features for esp
     offload

   - ethtool: fix incorrect datatype in set_eee ops

   - xdp: fix xdp_return_frame() kernel BUG throw for page_pool memory
     model

   - openvswitch: fix send of uninitialized stack memory in ct limit
     reply

  Misc:

   - udp: add get handling for UDP_GRO sockopt"

* tag 'net-5.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (182 commits)
  net: fix hangup on napi_disable for threaded napi
  net: hns3: Trivial spell fix in hns3 driver
  lan743x: fix ethernet frame cutoff issue
  net: ipv6: check for validity before dereferencing cfg->fc_nlinfo.nlh
  net: dsa: lantiq_gswip: Configure all remaining GSWIP_MII_CFG bits
  net: dsa: lantiq_gswip: Don't use PHY auto polling
  net: sched: sch_teql: fix null-pointer dereference
  ipv6: report errors for iftoken via netlink extack
  net: sched: fix err handler in tcf_action_init()
  net: sched: fix action overwrite reference counting
  Revert "net: sched: bump refcount for new action in ACT replace mode"
  ice: fix memory leak of aRFS after resuming from suspend
  i40e: Fix sparse warning: missing error code 'err'
  i40e: Fix sparse error: 'vsi->netdev' could be null
  i40e: Fix sparse error: uninitialized symbol 'ring'
  i40e: Fix sparse errors in i40e_txrx.c
  i40e: Fix parameters in aq_get_phy_register()
  nl80211: fix beacon head validation
  bpf, x86: Validate computation of branch displacements for x86-32
  bpf, x86: Validate computation of branch displacements for x86-64
  ...

Pull io_uring fixes from Jens Axboe:
 "Two minor fixups for the reissue logic, and one for making sure that
  unbounded work is canceled on io-wq exit"

* tag 'io_uring-5.12-2021-04-09' of git://git.kernel.dk/linux-block:
  io-wq: cancel unbounded works on io-wq destroy
  io_uring: fix rw req completion
  io_uring: clear F_REISSUE right after getting it

When LATENCYTOP, LOCKDEP, or FAULT_INJECTION_STACKTRACE_FILTER is
enabled and ARCH_WANT_FRAME_POINTERS is disabled, Kbuild gives a warning
such as:

  WARNING: unmet direct dependencies detected for FRAME_POINTER
    Depends on [n]: DEBUG_KERNEL [=y] && (M68K || UML || SUPERH) || ARCH_WANT_FRAME_POINTERS [=n] || MCOUNT [=n]
    Selected by [y]:
    - LATENCYTOP [=y] && DEBUG_KERNEL [=y] && STACKTRACE_SUPPORT [=y] && PROC_FS [=y] && !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM && !ARC && !X86

Depending on ARCH_WANT_FRAME_POINTERS causes a recursive dependency
error.  ARCH_WANT_FRAME_POINTERS is to be selected by the architecture,
and is not supposed to be overridden by other config options.

Link: https://lkml.kernel.org/r/20210329165329.27994-1-julianbraha@gmail.comSigned-off-by: Julian Braha <julianbraha@gmail.com>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Necip Fazil Yildiran <fazilyildiran@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

On systems with KPTI enabled, we can currently observe the following
warning:

  BUG: using smp_processor_id() in preemptible
  caller is invalidate_user_asid+0x13/0x50
  CPU: 6 PID: 1075 Comm: dmesg Not tainted 5.12.0-rc4-gda4a2b1a5479-kfence_1+ #1
  Hardware name: Hewlett-Packard HP Pro 3500 Series/2ABF, BIOS 8.11 10/24/2012
  Call Trace:
   dump_stack+0x7f/0xad
   check_preemption_disabled+0xc8/0xd0
   invalidate_user_asid+0x13/0x50
   flush_tlb_one_kernel+0x5/0x20
   kfence_protect+0x56/0x80
   ...

While it normally makes sense to require preemption to be off, so that
the expected CPU's TLB is flushed and not another, in our case it really
is best-effort (see comments in kfence_protect_page()).

Avoid the warning by disabling preemption around flush_tlb_one_kernel().

Link: https://lore.kernel.org/lkml/YGIDBAboELGgMgXy@elver.google.com/
Link: https://lkml.kernel.org/r/20210330065737.652669-1-elver@google.comSigned-off-by: Marco Elver <elver@google.com>
Reported-by: Tomi Sarvela <tomi.p.sarvela@intel.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Local `unused' is intentionally unused - it is there to suppress
__must_check warnings.
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lkml.kernel.org/r/202104050216.HflRxfJm-lkp@intel.com
Cc: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When page poisoning is enabled, it accesses memory that is marked as
poisoned by KASAN, which leas to false-positive KASAN reports.

Suppress the reports by adding KASAN annotations to unpoison_page()
(poison_page() already has them).

Link: https://lkml.kernel.org/r/2dc799014d31ac13fd97bd906bad33e16376fc67.1617118501.git.andreyknvl@google.comSigned-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

I encountered a hung task issue, but not a performance one.  I run DIO
on a device (need lba continuous, for example open channel ssd), maybe
hungtask in below case:

  DIO:						Checkpoint:
  get addr A(at boundary), merge into BIO,
  no submit because boundary missing
						flush dirty data(get addr A+1), wait IO(A+1)
						writeback timeout, because DIO(A) didn't submit
  get addr A+2 fail, because checkpoint is doing

dio_send_cur_page() may clear sdio->boundary, so prevent it from missing
a boundary.

Link: https://lkml.kernel.org/r/20210322042253.38312-1-jack.qiu@huawei.com
Fixes: b1058b98 ("direct-io: submit bio after boundary buffer is added to it")
Signed-off-by: Jack Qiu <jack.qiu@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ia64 has two stacks:

 - memory stack (or stack), pointed at by by r12

 - register backing store (register stack), pointed at by
   ar.bsp/ar.bspstore with complications around dirty
   register frame on CPU.

In [1] Dmitry noticed that PTRACE_GET_SYSCALL_INFO returns the register
stack instead memory stack.

The bug comes from the fact that user_stack_pointer() and
current_user_stack_pointer() don't return the same register:

  ulong user_stack_pointer(struct pt_regs *regs) { return regs->ar_bspstore; }
  #define current_user_stack_pointer() (current_pt_regs()->r12)

The change gets both back in sync.

I think ptrace(PTRACE_GET_SYSCALL_INFO) is the only affected user by
this bug on ia64.

The change fixes 'rt_sigreturn.gen.test' strace test where it was
observed initially.

Link: https://bugs.gentoo.org/769614 [1]
Link: https://lkml.kernel.org/r/20210331084447.2561532-1-slyfox@gentoo.orgSigned-off-by: Sergei Trofimovich <slyfox@gentoo.org>
Reported-by: Dmitry V. Levin <ldv@altlinux.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The following deadlock is detected:

  truncate -> setattr path is waiting for pending direct IO to be done (inode->i_dio_count become zero) with inode->i_rwsem held (down_write).

  PID: 14827  TASK: ffff881686a9af80  CPU: 20  COMMAND: "ora_p005_hrltd9"
   #0  __schedule at ffffffff818667cc
   #1  schedule at ffffffff81866de6
   #2  inode_dio_wait at ffffffff812a2d04
   #3  ocfs2_setattr at ffffffffc05f322e [ocfs2]
   #4  notify_change at ffffffff812a5a09
   #5  do_truncate at ffffffff812808f5
   #6  do_sys_ftruncate.constprop.18 at ffffffff81280cf2
   #7  sys_ftruncate at ffffffff81280d8e
   #8  do_syscall_64 at ffffffff81003949
   #9  entry_SYSCALL_64_after_hwframe at ffffffff81a001ad

dio completion path is going to complete one direct IO (decrement
inode->i_dio_count), but before that it hung at locking inode->i_rwsem:

   #0  __schedule+700 at ffffffff818667cc
   #1  schedule+54 at ffffffff81866de6
   #2  rwsem_down_write_failed+536 at ffffffff8186aa28
   #3  call_rwsem_down_write_failed+23 at ffffffff8185a1b7
   #4  down_write+45 at ffffffff81869c9d
   #5  ocfs2_dio_end_io_write+180 at ffffffffc05d5444 [ocfs2]
   #6  ocfs2_dio_end_io+85 at ffffffffc05d5a85 [ocfs2]
   #7  dio_complete+140 at ffffffff812c873c
   #8  dio_aio_complete_work+25 at ffffffff812c89f9
   #9  process_one_work+361 at ffffffff810b1889
  #10  worker_thread+77 at ffffffff810b233d
  #11  kthread+261 at ffffffff810b7fd5
  #12  ret_from_fork+62 at ffffffff81a0035e

Thus above forms ABBA deadlock.  The same deadlock was mentioned in
upstream commit 28f5a8a7 ("ocfs2: should wait dio before inode lock
in ocfs2_setattr()").  It seems that that commit only removed the
cluster lock (the victim of above dead lock) from the ABBA deadlock
party.

End-user visible effects: Process hang in truncate -> ocfs2_setattr path
and other processes hang at ocfs2_dio_end_io_write path.

This is to fix the deadlock itself.  It removes inode_lock() call from
dio completion path to remove the deadlock and add ip_alloc_sem lock in
setattr path to synchronize the inode modifications.

[wen.gang.wang@oracle.com: remove the "had_alloc_lock" as suggested]
  Link: https://lkml.kernel.org/r/20210402171344.1605-1-wen.gang.wang@oracle.com

Link: https://lkml.kernel.org/r/20210331203654.3911-1-wen.gang.wang@oracle.comSigned-off-by: Wengang Wang <wen.gang.wang@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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

LLVM changed the expected function signature for llvm_gcda_emit_function()
in the clang-11 release.  Users of clang-11 or newer may have noticed
their kernels producing invalid coverage information:

  $ llvm-cov gcov -a -c -u -f -b <input>.gcda -- gcno=<input>.gcno
  1 <func>: checksum mismatch, \
    (<lineno chksum A>, <cfg chksum B>) != (<lineno chksum A>, <cfg chksum C>)
  2 Invalid .gcda File!
  ...

Fix up the function signatures so calling this function interprets its
parameters correctly and computes the correct cfg checksum.  In
particular, in clang-11, the additional checksum is no longer optional.

Link: https://reviews.llvm.org/rG25544ce2df0daa4304c07e64b9c8b0f7df60c11d
Link: https://lkml.kernel.org/r/20210408184631.1156669-1-ndesaulniers@google.comReported-by: Prasad Sodagudi <psodagud@quicinc.com>
Tested-by: Prasad Sodagudi <psodagud@quicinc.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Cc: <stable@vger.kernel.org>	[5.4+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit cb9f753a ("mm: fix races between swapoff and flush dcache")
updated flush_dcache_page implementations on several architectures to
use page_mapping_file() in order to avoid races between page_mapping()
and swapoff().

This update missed arch/nds32 and there is a possibility of a race
there.

Replace page_mapping() with page_mapping_file() in nds32 implementation
of flush_dcache_page().

Link: https://lkml.kernel.org/r/20210330175126.26500-1-rppt@kernel.org
Fixes: cb9f753a ("mm: fix races between swapoff and flush dcache")
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Greentime Hu <green.hu@gmail.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When we do coredump for user process signal, this may be an SIGBUS signal
with BUS_MCEERR_AR or BUS_MCEERR_AO code, which means this signal is
resulted from ECC memory fail like SRAR or SRAO, we expect the memory
recovery work is finished correctly, then the get_dump_page() will not
return the error page as its process pte is set invalid by
memory_failure().

But memory_failure() may fail, and the process's related pte may not be
correctly set invalid, for current code, we will return the poison page,
get it dumped, and then lead to system panic as its in kernel code.

So check the poison status in get_dump_page(), and if TRUE, return NULL.

There maybe other scenario that is also better to check the posion status
and not to panic, so make a wrapper for this check, Thanks to David's
suggestion(<david@redhat.com>).

[akpm@linux-foundation.org: s/0/false/]
[yaoaili@kingsoft.com: is_page_poisoned() arg cannot be null, per Matthew]

Link: https://lkml.kernel.org/r/20210322115233.05e4e82a@alex-virtual-machine
Link: https://lkml.kernel.org/r/20210319104437.6f30e80d@alex-virtual-machineSigned-off-by: Aili Yao <yaoaili@kingsoft.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Aili Yao <yaoaili@kingsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>