Currently we start transaction for mapping every extent for writing
using direct IO. This is unnecessary when we know we are overwriting
already allocated blocks and the overhead of starting a transaction can
be significant especially for multithreaded workloads doing small writes.
Use iomap operations that avoid starting a transaction for direct IO
overwrites.

This improves throughput of 4k random writes - fio jobfile:
[global]
rw=randrw
norandommap=1
invalidate=0
bs=4k
numjobs=16
time_based=1
ramp_time=30
runtime=120
group_reporting=1
ioengine=psync
direct=1
size=16G
filename=file1.0.0:file1.0.1:file1.0.2:file1.0.3:file1.0.4:file1.0.5:file1.0.6:file1.0.7:file1.0.8:file1.0.9:file1.0.10:file1.0.11:file1.0.12:file1.0.13:file1.0.14:file1.0.15:file1.0.16:file1.0.17:file1.0.18:file1.0.19:file1.0.20:file1.0.21:file1.0.22:file1.0.23:file1.0.24:file1.0.25:file1.0.26:file1.0.27:file1.0.28:file1.0.29:file1.0.30:file1.0.31
file_service_type=random
nrfiles=32

from 3018MB/s to 4059MB/s in my test VM running test against simulated
pmem device (note that before iomap conversion, this workload was able
to achieve 3708MB/s because old direct IO path avoided transaction start
for overwrites as well). For dax, the win is even larger improving
throughput from 3042MB/s to 4311MB/s.
Reported-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191218174433.19380-1-jack@suse.czSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Make {first,last}_error_{ino,block,line,func,errcode} available via
sysfs.

Also add a missing newline for {first,last}_error_time.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

This allows us to test various error handling code paths

Link: https://lore.kernel.org/r/20191209012317.59398-1-tytso@mit.eduSigned-off-by: Theodore Ts'o <tytso@mit.edu>

This allows the cause of an ext4_error() report to be categorized
based on whether it was triggered due to an I/O error, or an memory
allocation error, or other possible causes.  Most errors are caused by
a detected file system inconsistency, so the default code stored in
the superblock will be EXT4_ERR_EFSCORRUPTED.

Link: https://lore.kernel.org/r/20191204032335.7683-1-tytso@mit.eduSigned-off-by: Theodore Ts'o <tytso@mit.edu>

These are ilock patches which helps improve the current inode lock scalabiliy
problem in ext4 DIO mixed read/write workload case. The problem was first
reported by Joseph [1]. This should help improve mixed read/write workload
cases for databases which use directIO.

These patches are based upon upstream discussion with Jan Kara & Joseph [2].

The problem really is that in case of DIO overwrites, we start with
a exclusive lock and then downgrade it later to shared lock. This causes a
scalability problem in case of mixed DIO read/write workload case.
i.e. if we have any ongoing DIO reads and then comes a DIO writes,
(since writes starts with excl. inode lock) then it has to wait until the
shared lock is released (which only happens when DIO read is completed).
Same is true for vice versa as well.
The same can be easily observed with perf-tools trace analysis [3].

For more details, including performance numbers, please see [4].

[1] https://lore.kernel.org/linux-ext4/1566871552-60946-4-git-send-email-joseph.qi@linux.alibaba.com/
[2] https://lore.kernel.org/linux-ext4/20190910215720.GA7561@quack2.suse.cz/
[3] https://raw.githubusercontent.com/riteshharjani/LinuxStudy/master/ext4/perf.report
[4] https://lore.kernel.org/r/20191212055557.11151-1-riteshh@linux.ibm.com

We were using shared locking only in case of dioread_nolock mount option in case
of DIO overwrites. This mount condition is not needed anymore with current code,
since:-

1. No race between buffered writes & DIO overwrites. Since buffIO writes takes
exclusive lock & DIO overwrites will take shared locking. Also DIO path will
make sure to flush and wait for any dirty page cache data.

2. No race between buffered reads & DIO overwrites, since there is no block
allocation that is possible with DIO overwrites. So no stale data exposure
should happen. Same is the case between DIO reads & DIO overwrites.

3. Also other paths like truncate is protected, since we wait there for any DIO
in flight to be over.
Reviewed-by: Jan Kara <jack@suse.cz>
Tested-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20191212055557.11151-4-riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Earlier there was no shared lock in DIO read path. But this patch
(16c54688: ext4: Allow parallel DIO reads)
simplified some of the locking mechanism while still allowing for parallel DIO
reads by adding shared lock in inode DIO read path.

But this created problem with mixed read/write workload. It is due to the fact
that in DIO path, we first start with exclusive lock and only when we determine
that it is a ovewrite IO, we downgrade the lock. This causes the problem, since
we still have shared locking in DIO reads.

So, this patch tries to fix this issue by starting with shared lock and then
switching to exclusive lock only when required based on ext4_dio_write_checks().

Other than that, it also simplifies below cases:-

1. Simplified ext4_unaligned_aio API to ext4_unaligned_io. Previous API was
abused in the sense that it was not really checking for AIO anywhere also it
used to check for extending writes. So this API was renamed and simplified to
ext4_unaligned_io() which actully only checks if the IO is really unaligned.

Now, in case of unaligned direct IO, iomap_dio_rw needs to do zeroing of partial
block and that will require serialization against other direct IOs in the same
block. So we take a exclusive inode lock for any unaligned DIO. In case of AIO
we also need to wait for any outstanding IOs to complete so that conversion from
unwritten to written is completed before anyone try to map the overlapping block.
Hence we take exclusive inode lock and also wait for inode_dio_wait() for
unaligned DIO case. Please note since we are anyway taking an exclusive lock in
unaligned IO, inode_dio_wait() becomes a no-op in case of non-AIO DIO.

2. Added ext4_extending_io(). This checks if the IO is extending the file.

3. Added ext4_dio_write_checks(). In this we start with shared inode lock and
only switch to exclusive lock if required. So in most cases with aligned,
non-extending, dioread_nolock & overwrites, it tries to write with a shared
lock. If not, then we restart the operation in ext4_dio_write_checks(), after
acquiring exclusive lock.
Reviewed-by: Jan Kara <jack@suse.cz>
Tested-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20191212055557.11151-3-riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Apparently our current rwsem code doesn't like doing the trylock, then
lock for real scheme.  So change our dax read/write methods to just do the
trylock for the RWF_NOWAIT case.
This seems to fix AIM7 regression in some scalable filesystems upto ~25%
in some cases. Claimed in commit 942491c9 ("xfs: fix AIM7 regression")
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Matthew Bobrowski <mbobrowski@mbobrowski.org>
Tested-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20191212055557.11151-2-riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

In commit 7963e5ac ("ext4: treat buffers with write errors as
containing valid data") we missed changing ext4_sb_bread() to use
ext4_buffer_uptodate().  So fix this oversight.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Pull vfs fixes from Al Viro:
 "Eric's s_inodes softlockup fixes + Jan's fix for recent regression
  from pipe rework"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: call fsnotify_sb_delete after evict_inodes
  fs: avoid softlockups in s_inodes iterators
  pipe: Fix bogus dereference in iov_iter_alignment()

Pull xfs fixes from Darrick Wong:
 "Fix a few bugs that could lead to corrupt files, fsck complaints, and
  filesystem crashes:

   - Minor documentation fixes

   - Fix a file corruption due to read racing with an insert range
     operation.

   - Fix log reservation overflows when allocating large rt extents

   - Fix a buffer log item flags check

   - Don't allow administrators to mount with sunit= options that will
     cause later xfs_repair complaints about the root directory being
     suspicious because the fs geometry appeared inconsistent

   - Fix a non-static helper that should have been static"

* tag 'xfs-5.5-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: Make the symbol 'xfs_rtalloc_log_count' static
  xfs: don't commit sunit/swidth updates to disk if that would cause repair failures
  xfs: split the sunit parameter update into two parts
  xfs: refactor agfl length computation function
  libxfs: resync with the userspace libxfs
  xfs: use bitops interface for buf log item AIL flag check
  xfs: fix log reservation overflows when allocating large rt extents
  xfs: stabilize insert range start boundary to avoid COW writeback race
  xfs: fix Sphinx documentation warning

Pull ext4 bug fixes from Ted Ts'o:
 "Ext4 bug fixes, including a regression fix"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: clarify impact of 'commit' mount option
  ext4: fix unused-but-set-variable warning in ext4_add_entry()
  jbd2: fix kernel-doc notation warning
  ext4: use RCU API in debug_print_tree
  ext4: validate the debug_want_extra_isize mount option at parse time
  ext4: reserve revoke credits in __ext4_new_inode
  ext4: unlock on error in ext4_expand_extra_isize()
  ext4: optimize __ext4_check_dir_entry()
  ext4: check for directory entries too close to block end
  ext4: fix ext4_empty_dir() for directories with holes

Pull block fixes from Jens Axboe:
 "Let's try this one again, this time without the compat_ioctl changes.
  We've got those fixed up, but that can go out next week.

  This contains:

   - block queue flush lockdep annotation (Bart)

   - Type fix for bsg_queue_rq() (Bart)

   - Three dasd fixes (Stefan, Jan)

   - nbd deadlock fix (Mike)

   - Error handling bio user map fix (Yang)

   - iocost fix (Tejun)

   - sbitmap waitqueue addition fix that affects the kyber IO scheduler
     (David)"

* tag 'block-5.5-20191221' of git://git.kernel.dk/linux-block:
  sbitmap: only queue kyber's wait callback if not already active
  block: fix memleak when __blk_rq_map_user_iov() is failed
  s390/dasd: fix typo in copyright statement
  s390/dasd: fix memleak in path handling error case
  s390/dasd/cio: Interpret ccw_device_get_mdc return value correctly
  block: Fix a lockdep complaint triggered by request queue flushing
  block: Fix the type of 'sts' in bsg_queue_rq()
  block: end bio with BLK_STS_AGAIN in case of non-mq devs and REQ_NOWAIT
  nbd: fix shutdown and recv work deadlock v2
  iocost: over-budget forced IOs should schedule async delay

Pull KVM fixes from Paolo Bonzini:
 "PPC:
   - Fix a bug where we try to do an ultracall on a system without an
     ultravisor

  KVM:
   - Fix uninitialised sysreg accessor
   - Fix handling of demand-paged device mappings
   - Stop spamming the console on IMPDEF sysregs
   - Relax mappings of writable memslots
   - Assorted cleanups

  MIPS:
   - Now orphan, James Hogan is stepping down

  x86:
   - MAINTAINERS change, so long Radim and thanks for all the fish
   - supported CPUID fixes for AMD machines without SPEC_CTRL"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  MAINTAINERS: remove Radim from KVM maintainers
  MAINTAINERS: Orphan KVM for MIPS
  kvm: x86: Host feature SSBD doesn't imply guest feature AMD_SSBD
  kvm: x86: Host feature SSBD doesn't imply guest feature SPEC_CTRL_SSBD
  KVM: PPC: Book3S HV: Don't do ultravisor calls on systems without ultravisor
  KVM: arm/arm64: Properly handle faulting of device mappings
  KVM: arm64: Ensure 'params' is initialised when looking up sys register
  KVM: arm/arm64: Remove excessive permission check in kvm_arch_prepare_memory_region
  KVM: arm64: Don't log IMP DEF sysreg traps
  KVM: arm64: Sanely ratelimit sysreg messages
  KVM: arm/arm64: vgic: Use wrapper function to lock/unlock all vcpus in kvm_vgic_create()
  KVM: arm/arm64: vgic: Fix potential double free dist->spis in __kvm_vgic_destroy()
  KVM: arm/arm64: Get rid of unused arg in cpu_init_hyp_mode()

Pull RISC-V fixes from Paul Walmsley:
 "Several fixes, and one cleanup, for RISC-V.

  Fixes:

   - Fix an error in a Kconfig file that resulted in an undefined
     Kconfig option "CONFIG_CONFIG_MMU"

   - Fix undefined Kconfig option "CONFIG_CONFIG_MMU"

   - Fix scratch register clearing in M-mode (affects nommu users)

   - Fix a mismerge on my part that broke the build for
     CONFIG_SPARSEMEM_VMEMMAP users

  Cleanup:

   - Move SiFive L2 cache-related code to drivers/soc, per request"

* tag 'riscv/for-v5.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: move sifive_l2_cache.c to drivers/soc
  riscv: define vmemmap before pfn_to_page calls
  riscv: fix scratch register clearing in M-mode.
  riscv: Fix use of undefined config option CONFIG_CONFIG_MMU

Pull networking fixes from David Miller:

 1) Several nf_flow_table_offload fixes from Pablo Neira Ayuso,
    including adding a missing ipv6 match description.

 2) Several heap overflow fixes in mwifiex from qize wang and Ganapathi
    Bhat.

 3) Fix uninit value in bond_neigh_init(), from Eric Dumazet.

 4) Fix non-ACPI probing of nxp-nci, from Stephan Gerhold.

 5) Fix use after free in tipc_disc_rcv(), from Tuong Lien.

 6) Enforce limit of 33 tail calls in mips and riscv JIT, from Paul
    Chaignon.

 7) Multicast MAC limit test is off by one in qede, from Manish Chopra.

 8) Fix established socket lookup race when socket goes from
    TCP_ESTABLISHED to TCP_LISTEN, because there lacks an intervening
    RCU grace period. From Eric Dumazet.

 9) Don't send empty SKBs from tcp_write_xmit(), also from Eric Dumazet.

10) Fix active backup transition after link failure in bonding, from
    Mahesh Bandewar.

11) Avoid zero sized hash table in gtp driver, from Taehee Yoo.

12) Fix wrong interface passed to ->mac_link_up(), from Russell King.

13) Fix DSA egress flooding settings in b53, from Florian Fainelli.

14) Memory leak in gmac_setup_txqs(), from Navid Emamdoost.

15) Fix double free in dpaa2-ptp code, from Ioana Ciornei.

16) Reject invalid MTU values in stmmac, from Jose Abreu.

17) Fix refcount leak in error path of u32 classifier, from Davide
    Caratti.

18) Fix regression causing iwlwifi firmware crashes on boot, from Anders
    Kaseorg.

19) Fix inverted return value logic in llc2 code, from Chan Shu Tak.

20) Disable hardware GRO when XDP is attached to qede, frm Manish
    Chopra.

21) Since we encode state in the low pointer bits, dst metrics must be
    at least 4 byte aligned, which is not necessarily true on m68k. Add
    annotations to fix this, from Geert Uytterhoeven.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (160 commits)
  sfc: Include XDP packet headroom in buffer step size.
  sfc: fix channel allocation with brute force
  net: dst: Force 4-byte alignment of dst_metrics
  selftests: pmtu: fix init mtu value in description
  hv_netvsc: Fix unwanted rx_table reset
  net: phy: ensure that phy IDs are correctly typed
  mod_devicetable: fix PHY module format
  qede: Disable hardware gro when xdp prog is installed
  net: ena: fix issues in setting interrupt moderation params in ethtool
  net: ena: fix default tx interrupt moderation interval
  net/smc: unregister ib devices in reboot_event
  net: stmmac: platform: Fix MDIO init for platforms without PHY
  llc2: Fix return statement of llc_stat_ev_rx_null_dsap_xid_c (and _test_c)
  net: hisilicon: Fix a BUG trigered by wrong bytes_compl
  net: dsa: ksz: use common define for tag len
  s390/qeth: don't return -ENOTSUPP to userspace
  s390/qeth: fix promiscuous mode after reset
  s390/qeth: handle error due to unsupported transport mode
  cxgb4: fix refcount init for TC-MQPRIO offload
  tc-testing: initial tdc selftests for cls_u32
  ...

LTP pipeio_1 test is hanging with v5.5-rc2-385-gb8e382a1,
with read side observing empty pipe and sleeping and write
side running out of space and then sleeping as well. In this
scenario there are 5 writers and 1 reader.

Problem is that after pipe_write() reacquires pipe lock, it
re-checks for empty pipe with potentially stale 'head' and
doesn't wake up read side anymore. pipe->tail can advance
beyond 'head', because there are multiple writers.

Use pipe->head for empty pipe check after reacquiring lock
to observe current state.

Testing: With patch, LTP pipeio_1 ran successfully in loop for 1 hour.
         Without patch it hanged within a minute.

Fixes: 1b6b26ae ("pipe: fix and clarify pipe write wakeup logic")
Reported-by: Rachel Sibley <rasibley@redhat.com>
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'kvm-ppc-fixes-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into kvm-master

PPC KVM fix for 5.5

- Fix a bug where we try to do an ultracall on a system without an
  ultravisor.

Radim's kernel.org email is bouncing, which I take as a signal that
he is not really able to deal with KVM at this time.  Make MAINTAINERS
match the effective value of KVM's bus factor.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

I haven't been active for 18 months, and don't have the hardware set up
to test KVM for MIPS, so mark it as orphaned and remove myself as
maintainer. Hopefully somebody from MIPS can pick this up.
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: kvm@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The description of 'commit' mount option dates back to ext3 times.
Update the description to match current meaning for ext4.
Reported-by: Paul Richards <paul.richards@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191218111210.14161-1-jack@suse.czSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Warning is found when compile with "-Wunused-but-set-variable":

fs/ext4/namei.c: In function ‘ext4_add_entry’:
fs/ext4/namei.c:2167:23: warning: variable ‘sbi’ set but not used
[-Wunused-but-set-variable]
  struct ext4_sb_info *sbi;
                       ^~~
Fix this by moving the variable @sbi under CONFIG_UNICODE.
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/cb5eb904-224a-9701-c38f-cb23514b1fff@huawei.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Pull tracing fixes from Steven Rostedt:

 - Fix memory leak on error path of process_system_preds()

 - Lock inversion fix with updating tgid recording option

 - Fix histogram compare function on big endian machines

 - Fix histogram trigger function on big endian machines

 - Make trace_printk() irq sync on init for kprobe selftest correctness

* tag 'trace-v5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix endianness bug in histogram trigger
  samples/trace_printk: Wait for IRQ work to finish
  tracing: Fix lock inversion in trace_event_enable_tgid_record()
  tracing: Have the histogram compare functions convert to u64 first
  tracing: Avoid memory leak in process_system_preds()

Pull libnvdimm fix from Dan Williams:
 "A minor regression fix.

  The libnvdimm unit tests were expecting to mock calls to
  ioremap_nocache() which disappeared in v5.5-rc1. This fix has appeared
  in -next and collided with some cleanups that Christoph has planned
  for v5.6, but he will fix up his branch once this goes in.

  Summary:

   - Restore the operation of the libnvdimm unit tests after the removal
     of ioremap_nocache()"

* tag 'libnvdimm-fix-5.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  tools/testing/nvdimm: Fix mock support for ioremap

At least on PA-RISC and s390 synthetic histogram triggers are failing
selftests because trace_event_raw_event_synth() always writes a 64 bit
values, but the reader expects a field->size sized value. On little endian
machines this doesn't hurt, but on big endian this makes the reader always
read zero values.

Link: http://lore.kernel.org/linux-trace-devel/20191218074427.96184-4-svens@linux.ibm.com

Cc: stable@vger.kernel.org
Fixes: 4b147936 ("tracing: Add support for 'synthetic' events")
Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

trace_printk schedules work via irq_work_queue(), but doesn't
wait until it was processed. The kprobe_module.tc testcase does:

:;: "Load module again, which means the event1 should be recorded";:
modprobe trace-printk
grep "event1:" trace

so the grep which checks the trace file might run before the irq work
was processed. Fix this by adding a irq_work_sync().

Link: http://lore.kernel.org/linux-trace-devel/20191218074427.96184-3-svens@linux.ibm.com

Cc: stable@vger.kernel.org
Fixes: af2a0750 ("selftests/ftrace: Improve kprobe on module testcase to load/unload module")
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

       Task T2                             Task T3
trace_options_core_write()            subsystem_open()

 mutex_lock(trace_types_lock)           mutex_lock(event_mutex)

 set_tracer_flag()

   trace_event_enable_tgid_record()       mutex_lock(trace_types_lock)

    mutex_lock(event_mutex)

This gives a circular dependency deadlock between trace_types_lock and
event_mutex. To fix this invert the usage of trace_types_lock and
event_mutex in trace_options_core_write(). This keeps the sequence of
lock usage consistent.

Link: http://lkml.kernel.org/r/0101016eef175e38-8ca71caf-a4eb-480d-a1e6-6f0bbc015495-000000@us-west-2.amazonses.com

Cc: stable@vger.kernel.org
Fixes: d914ba37 ("tracing: Add support for recording tgid of tasks")
Signed-off-by: Prateek Sood <prsood@codeaurora.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Pull s390 fixes from Vasily Gorbik:

 - Fix unwinding from irq context of interrupted user process.

 - Add purgatory build missing symbols check. That helped to uncover and
   fix missing symbols when built with kasan support enabled.

 - Couple of ftrace fixes. Avoid broken stack trace and fix recursion
   loop in function_graph tracer.

* tag 's390-5.5-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/ftrace: save traced function caller
  s390/unwind: stop gracefully at user mode pt_regs in irq stack
  s390/purgatory: do not build purgatory with kcov, kasan and friends
  s390/purgatory: Make sure we fail the build if purgatory has missing symbols
  s390/ftrace: fix endless recursion in function_graph tracer

Pull scheduler fixes from Ingo Molnar:
 "Misc fixes: a (rare) PSI crash fix, a CPU affinity related balancing
  fix, and a toning down of active migration attempts"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/cfs: fix spurious active migration
  sched/fair: Fix find_idlest_group() to handle CPU affinity
  psi: Fix a division error in psi poll()
  sched/psi: Fix sampling error and rare div0 crashes with cgroups and high uptime

Pull perf fixes from Ingo Molnar:
 "Misc fixes: a BTS fix, a PT NMI handling fix, a PMU sysfs fix and an
  SRCU annotation"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Add SRCU annotation for pmus list walk
  perf/x86/intel: Fix PT PMI handling
  perf/x86/intel/bts: Fix the use of page_private()
  perf/x86: Fix potential out-of-bounds access

Merge tag 'kbuild-fixes-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - fix warning in out-of-tree 'make clean'

 - add READELF variable to the top Makefile

 - fix broken builds when LINUX_COMPILE_BY contains a backslash

 - fix build warning in kallsyms

 - fix NULL pointer access in expr_eq() in Kconfig

 - fix missing dependency on rsync in deb-pkg build

 - remove ---help--- from documentation

 - fix misleading documentation about directory descending

* tag 'kbuild-fixes-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: clarify the difference between obj-y and obj-m w.r.t. descending
  kconfig: remove ---help--- from documentation
  scripts: package: mkdebian: add missing rsync dependency
  kconfig: don't crash on NULL expressions in expr_eq()
  scripts/kallsyms: fix offset overflow of kallsyms_relative_base
  mkcompile_h: use printf for LINUX_COMPILE_BY
  mkcompile_h: git rid of UTS_TRUNCATE from LINUX_COMPILE_{BY,HOST}
  x86/boot: kbuild: allow readelf executable to be specified
  kbuild: fix 'No such file or directory' warning when cleaning

Kbuild descends into a directory by either 'y' or 'm', but there is an
important difference.

Kbuild combines the built-in objects into built-in.a in each directory.
The built-in.a in the directory visited by obj-y is merged into the
built-in.a in the parent directory. This merge happens recursively
when Kbuild is ascending back towards the top directory, then built-in
objects are linked into vmlinux eventually. This works properly only
when the Makefile specifying obj-y is reachable by the chain of obj-y.

On the other hand, Kbuild does not take built-in.a from the directory
visited by obj-m. This it, all the objects in that directory are
supposed to be modular. If Kbuild descends into a directory by obj-m,
but the Makefile in the sub-directory specifies obj-y, those objects
are just left orphan.

The current statement "Kbuild only uses this information to decide that
it needs to visit the directory" is misleading. Clarify the difference.
Reported-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Johan Hovold <johan@kernel.org>

Pul parisc fixes from Helge Deller:
 "Two build error fixes, one for the soft_offline_page() parameter
  change and one for a specific KEXEC/KEXEC_FILE configuration, as well
  as a compiler and a linker warning fix"

* 'parisc-5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Fix compiler warnings in debug_core.c
  parisc: soft_offline_page() now takes the pfn
  parisc: add missing __init annotation
  parisc: fix compilation when KEXEC=n and KEXEC_FILE=y

Pull xen fixes from Juergen Gross:
 "This contains two cleanup patches and a small series for supporting
  reloading the Xen block backend driver"

* tag 'for-linus-5.5b-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/grant-table: remove multiple BUG_ON on gnttab_interface
  xen-blkback: support dynamic unbind/bind
  xen/interface: re-define FRONT/BACK_RING_ATTACH()
  xenbus: limit when state is forced to closed
  xenbus: move xenbus_dev_shutdown() into frontend code...
  xen/blkfront: Adjust indentation in xlvbd_alloc_gendisk

Pull powerpc fixes from Michael Ellerman:
 "Two weeks worth of accumulated fixes:

   - A fix for a performance regression seen on PowerVM LPARs using
     dedicated CPUs, caused by our vcpu_is_preempted() returning true
     even for idle CPUs.

   - One of the ultravisor support patches broke KVM on big endian hosts
     in v5.4.

   - Our KUAP (Kernel User Access Prevention) code missed allowing
     access in __clear_user(), which could lead to an oops or erroneous
     SEGV when triggered via PTRACE_GETREGSET.

   - Two fixes for the ocxl driver, an open/remove race, and a memory
     leak in an error path.

   - A handful of other small fixes.

  Thanks to: Andrew Donnellan, Christian Zigotzky, Christophe Leroy,
  Christoph Hellwig, Daniel Axtens, David Hildenbrand, Frederic Barrat,
  Gautham R. Shenoy, Greg Kurz, Ihor Pasichnyk, Juri Lelli, Marcus
  Comstedt, Mike Rapoport, Parth Shah, Srikar Dronamraju, Vaidyanathan
  Srinivasan"

* tag 'powerpc-5.5-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  KVM: PPC: Book3S HV: Fix regression on big endian hosts
  powerpc: Fix __clear_user() with KUAP enabled
  powerpc/pseries/cmm: fix managed page counts when migrating pages between zones
  powerpc/8xx: fix bogus __init on mmu_mapin_ram_chunk()
  ocxl: Fix potential memory leak on context creation
  powerpc/irq: fix stack overflow verification
  powerpc: Ensure that swiotlb buffer is allocated from low memory
  powerpc/shared: Use static key to detect shared processor
  powerpc/vcpu: Assume dedicated processors as non-preempt
  ocxl: Fix concurrent AFU open and device removal

Pull x86 RAS fixes from Borislav Petkov:
 "Three urgent RAS fixes for the AMD side of things:

   - initialize struct mce.bank so that calculated error severity on AMD
     SMCA machines is correct

   - do not send IPIs early during bank initialization, when interrupts
     are disabled

   - a fix for when only a subset of MCA banks are enabled, which led to
     boot hangs on some new AMD CPUs"

* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Fix possibly incorrect severity calculation on AMD
  x86/MCE/AMD: Allow Reserved types to be overwritten in smca_banks[]
  x86/MCE/AMD: Do not use rdmsr_safe_on_cpu() in smca_configure()

Pull clk fixes from Stephen Boyd:
 "One core framework fix to walk the orphan list and match up clks to
  parents when clk providers register the DT provider after registering
  all their clks (as they should).

  Then a handful of driver fixes for the qcom, imx, and at91 drivers.

  The driver fixes are relatively small fixes for incorrect register
  settings or missing locks causing race conditions"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: qcom: Avoid SMMU/cx gdsc corner cases
  clk: qcom: gcc-sc7180: Fix setting flag for votable GDSCs
  clk: Move clk_core_reparent_orphans() under CONFIG_OF
  clk: at91: fix possible deadlock
  clk: walk orphan list on clock provider registration
  clk: imx: pll14xx: fix clk_pll14xx_wait_lock
  clk: imx: clk-imx7ulp: Add missing sentinel of ulp_div_table
  clk: imx: clk-composite-8m: add lock to gate/mux

Edward Cree says:

====================
sfc: fix bugs introduced by XDP patches

Two fixes for bugs introduced by the XDP support in the sfc driver.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Correct a mismatch between rx_page_buf_step and the actual step size
used when filling buffer pages.

This patch fixes the page overrun that occured when the MTU was set to
anything bigger than 1692.

Fixes: 3990a8ff ("sfc: allocate channels for XDP tx queues")
Signed-off-by: Charles McLachlan <cmclachlan@solarflare.com>
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>