As preparation to rework __percpu_down_read() move the
__this_cpu_inc() into it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200131151540.041600199@infradead.org

Use bool where possible.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200131151539.984626569@infradead.org

As preparation for replacing the embedded rwsem, give percpu-rwsem its
own lockdep_map.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200131151539.927625541@infradead.org

Once a lock class is zapped, all the lock chains that include the zapped
class are essentially useless. The lock_chain structure itself can be
reused, but not the corresponding chain_hlocks[] entries. Over time,
we will run out of chain_hlocks entries while there are still plenty
of other lockdep array entries available.

To fix this imbalance, we have to make chain_hlocks entries reusable
just like the others. As the freed chain_hlocks entries are in blocks of
various lengths. A simple bitmap like the one used in the other reusable
lockdep arrays isn't applicable. Instead the chain_hlocks entries are
put into bucketed lists (MAX_CHAIN_BUCKETS) of chain blocks.  Bucket 0
is the variable size bucket which houses chain blocks of size larger than
MAX_CHAIN_BUCKETS sorted in decreasing size order.  Initially, the whole
array is in one chain block (the primordial chain block) in bucket 0.

The minimum size of a chain block is 2 chain_hlocks entries. That will
be the minimum allocation size. In other word, allocation requests
for one chain_hlocks entry will cause 2-entry block to be returned and
hence 1 entry will be wasted.

Allocation requests for the chain_hlocks are fulfilled first by looking
for chain block of matching size. If not found, the first chain block
from bucket[0] (the largest one) is split. That can cause hlock entries
fragmentation and reduce allocation efficiency if a chain block of size >
MAX_CHAIN_BUCKETS is ever zapped and put back to after the primordial
chain block. So the MAX_CHAIN_BUCKETS must be large enough that this
should seldom happen.

By reusing the chain_hlocks entries, we are able to handle workloads
that add and zap a lot of lock classes without the risk of running out
of chain_hlocks entries as long as the total number of outstanding lock
classes at any time remain within a reasonable limit.

Two new tracking counters, nr_free_chain_hlocks & nr_large_chain_blocks,
are added to track the total number of chain_hlocks entries in the
free bucketed lists and the number of large chain blocks in buckets[0]
respectively. The nr_free_chain_hlocks replaces nr_chain_hlocks.

The nr_large_chain_blocks counter enables to see if we should increase
the number of buckets (MAX_CHAIN_BUCKETS) available so as to avoid to
avoid the fragmentation problem in bucket[0].

An internal nfsd test that ran for more than an hour and kept on
loading and unloading kernel modules could cause the following message
to be displayed.

  [ 4318.443670] BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!

The patched kernel was able to complete the test with a lot of free
chain_hlocks entries to spare:

  # cat /proc/lockdep_stats
     :
   dependency chains:                   18867 [max: 65536]
   dependency chain hlocks:             74926 [max: 327680]
   dependency chain hlocks lost:            0
     :
   zapped classes:                       1541
   zapped lock chains:                  56765
   large chain blocks:                      1

By changing MAX_CHAIN_BUCKETS to 3 and add a counter for the size of the
largest chain block. The system still worked and We got the following
lockdep_stats data:

   dependency chains:                   18601 [max: 65536]
   dependency chain hlocks used:        73133 [max: 327680]
   dependency chain hlocks lost:            0
     :
   zapped classes:                       1541
   zapped lock chains:                  56702
   large chain blocks:                  45165
   large chain block size:              20165

By running the test again, I was indeed able to cause chain_hlocks
entries to get lost:

   dependency chain hlocks used:        74806 [max: 327680]
   dependency chain hlocks lost:          575
     :
   large chain blocks:                  48737
   large chain block size:                  7

Due to the fragmentation, it is possible that the
"MAX_LOCKDEP_CHAIN_HLOCKS too low!" error can happen even if a lot of
of chain_hlocks entries appear to be free.

Fortunately, a MAX_CHAIN_BUCKETS value of 16 should be big enough that
few variable sized chain blocks, other than the initial one, should
ever be present in bucket 0.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200206152408.24165-7-longman@redhat.com

Add a new counter nr_zapped_lock_chains to track the number lock chains
that have been removed.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200206152408.24165-6-longman@redhat.com

If a lock chain contains a class that is zapped, the whole lock chain is
likely to be invalid. If the zapped class is at the end of the chain,
the partial chain without the zapped class should have been stored
already as the current code will store all its predecessor chains. If
the zapped class is somewhere in the middle, there is no guarantee that
the partial chain will actually happen. It may just clutter up the hash
and make searching slower. I would rather prefer storing the chain only
when it actually happens.

So just dump the corresponding chain_hlocks entries for now. A latter
patch will try to reuse the freed chain_hlocks entries.

This patch also changes the type of nr_chain_hlocks to unsigned integer
to be consistent with the other counters.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200206152408.24165-5-longman@redhat.com

The whole point of the lockdep dynamic key patch is to allow unused
locks to be removed from the lockdep data buffers so that existing
buffer space can be reused. However, there is no way to find out how
many unused locks are zapped and so we don't know if the zapping process
is working properly.

Add a new nr_zapped_classes counter to track that and show it in
/proc/lockdep_stats.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200206152408.24165-4-longman@redhat.com

Currently, the irq_context field of a lock chains displayed in
/proc/lockdep_chains is just a number. It is likely that many people
may not know what a non-zero number means. To make the information more
useful, print the actual irq names ("softirq" and "hardirq") instead.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200206152408.24165-3-longman@redhat.com

There are currently three counters to track the IRQ context of a lock
chain - nr_hardirq_chains, nr_softirq_chains and nr_process_chains.
They are incremented when a new lock chain is added, but they are
not decremented when a lock chain is removed. That causes some of the
statistic counts reported by /proc/lockdep_stats to be incorrect.
IRQ
Fix that by decrementing the right counter when a lock chain is removed.

Since inc_chains() no longer accesses hardirq_context and softirq_context
directly, it is moved out from the CONFIG_TRACE_IRQFLAGS conditional
compilation block.

Fixes: a0b0fd53 ("locking/lockdep: Free lock classes that are no longer in use")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200206152408.24165-2-longman@redhat.com

Pull cgroup fix from Tejun Heo:
 "I made a mistake while removing cgroup task list lazy init
  optimization making the root cgroup.procs show entries for the
  init_tasks. The zero entries doesn't cause critical failures but does
  make systemd print out warning messages during boot.

  Fix it by omitting init_tasks as they should be"

* 'for-5.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: init_tasks shouldn't be linked to the root cgroup

Pull SELinux fixes from Paul Moore:
 "Two small fixes: one fixes a locking problem in the recently merged
  label translation code, the other fixes an embarrassing 'binderfs' /
  'binder' filesystem name check"

* tag 'selinux-pr-20200210' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: fix sidtab string cache locking
  selinux: fix typo in filesystem name

Pull more Kbuild updates from Masahiro Yamada:

 - fix randconfig to generate a sane .config

 - rename hostprogs-y / always to hostprogs / always-y, which are more
   natual syntax.

 - optimize scripts/kallsyms

 - fix yes2modconfig and mod2yesconfig

 - make multiple directory targets ('make foo/ bar/') work

* tag 'kbuild-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: make multiple directory targets work
  kconfig: Invalidate all symbols after changing to y or m.
  kallsyms: fix type of kallsyms_token_table[]
  scripts/kallsyms: change table to store (strcut sym_entry *)
  scripts/kallsyms: rename local variables in read_symbol()
  kbuild: rename hostprogs-y/always to hostprogs/always-y
  kbuild: fix the document to use extra-y for vmlinux.lds
  kconfig: fix broken dependency in randconfig-generated .config

Pull new zonefs file system from Damien Le Moal:
 "Zonefs is a very simple file system exposing each zone of a zoned
  block device as a file.

  Unlike a regular file system with native zoned block device support
  (e.g. f2fs or the on-going btrfs effort), zonefs does not hide the
  sequential write constraint of zoned block devices to the user. As a
  result, zonefs is not a POSIX compliant file system. Its goal is to
  simplify the implementation of zoned block devices support in
  applications by replacing raw block device file accesses with a richer
  file based API, avoiding relying on direct block device file ioctls
  which may be more obscure to developers.

  One example of this approach is the implementation of LSM
  (log-structured merge) tree structures (such as used in RocksDB and
  LevelDB) on zoned block devices by allowing SSTables to be stored in a
  zone file similarly to a regular file system rather than as a range of
  sectors of a zoned device. The introduction of the higher level
  construct "one file is one zone" can help reducing the amount of
  changes needed in the application while at the same time allowing the
  use of zoned block devices with various programming languages other
  than C.

  Zonefs IO management implementation uses the new iomap generic code.
  Zonefs has been successfully tested using a functional test suite
  (available with zonefs userland format tool on github) and a prototype
  implementation of LevelDB on top of zonefs"

* tag 'zonefs-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs:
  zonefs: Add documentation
  fs: New zonefs file system

In order to allow the GICv4 code to link properly on 32bit ARM,
make sure we don't use 64bit divisions when it isn't strictly
necessary.

Fixes: 4e6437f1 ("irqchip/gic-v4.1: Ensure L2 vPE table is allocated at RD level")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull cifs fixes from Steve French:
 "13 cifs/smb3 patches, most from testing at the SMB3 plugfest this week:

   - Important fix for multichannel and for modefromsid mounts.

   - Two reconnect fixes

   - Addition of SMB3 change notify support

   - Backup tools fix

   - A few additional minor debug improvements (tracepoints and
     additional logging found useful during testing this week)"

* tag '5.6-rc-smb3-plugfest-patches' of git://git.samba.org/sfrench/cifs-2.6:
  smb3: Add defines for new information level, FileIdInformation
  smb3: print warning once if posix context returned on open
  smb3: add one more dynamic tracepoint missing from strict fsync path
  cifs: fix mode bits from dir listing when mounted with modefromsid
  cifs: fix channel signing
  cifs: add SMB3 change notification support
  cifs: make multichannel warning more visible
  cifs: fix soft mounts hanging in the reconnect code
  cifs: Add tracepoints for errors on flush or fsync
  cifs: log warning message (once) if out of disk space
  cifs: fail i/o on soft mounts if sessionsetup errors out
  smb3: fix problem with null cifs super block with previous patch
  SMB3: Backup intent flag missing from some more ops

Pull vboxfs from Al Viro:
 "This is the VirtualBox guest shared folder support by Hans de Goede,
  with fixups for fs_parse folded in to avoid bisection hazards from
  those API changes..."

* 'work.vboxsf' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: Add VirtualBox guest shared folder (vboxsf) support

Pull x86 fixes from Thomas Gleixner:
 "A set of fixes for X86:

   - Ensure that the PIT is set up when the local APIC is disable or
     configured in legacy mode. This is caused by an ordering issue
     introduced in the recent changes which skip PIT initialization when
     the TSC and APIC frequencies are already known.

   - Handle malformed SRAT tables during early ACPI parsing which caused
     an infinite loop anda boot hang.

   - Fix a long standing race in the affinity setting code which affects
     PCI devices with non-maskable MSI interrupts. The problem is caused
     by the non-atomic writes of the MSI address (destination APIC id)
     and data (vector) fields which the device uses to construct the MSI
     message. The non-atomic writes are mandated by PCI.

     If both fields change and the device raises an interrupt after
     writing address and before writing data, then the MSI block
     constructs a inconsistent message which causes interrupts to be
     lost and subsequent malfunction of the device.

     The fix is to redirect the interrupt to the new vector on the
     current CPU first and then switch it over to the new target CPU.
     This allows to observe an eventually raised interrupt in the
     transitional stage (old CPU, new vector) to be observed in the APIC
     IRR and retriggered on the new target CPU and the new vector.

     The potential spurious interrupts caused by this are harmless and
     can in the worst case expose a buggy driver (all handlers have to
     be able to deal with spurious interrupts as they can and do happen
     for various reasons).

   - Add the missing suspend/resume mechanism for the HYPERV hypercall
     page which prevents resume hibernation on HYPERV guests. This
     change got lost before the merge window.

   - Mask the IOAPIC before disabling the local APIC to prevent
     potentially stale IOAPIC remote IRR bits which cause stale
     interrupt lines after resume"

* tag 'x86-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic: Mask IOAPIC entries when disabling the local APIC
  x86/hyperv: Suspend/resume the hypercall page for hibernation
  x86/apic/msi: Plug non-maskable MSI affinity race
  x86/boot: Handle malformed SRAT tables during early ACPI parsing
  x86/timer: Don't skip PIT setup when APIC is disabled or in legacy mode

Pull SMP fixes from Thomas Gleixner:
 "Two fixes for the SMP related functionality:

   - Make the UP version of smp_call_function_single() match SMP
     semantics when called for a not available CPU. Instead of emitting
     a warning and assuming that the function call target is CPU0,
     return a proper error code like the SMP version does.

   - Remove a superfluous check in smp_call_function_many_cond()"

* tag 'smp-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smp/up: Make smp_call_function_single() match SMP semantics
  smp: Remove superfluous cond_func check in smp_call_function_many_cond()

Pull perf fixes from Thomas Gleixner:
 "A set of fixes and improvements for the perf subsystem:

  Kernel fixes:

   - Install cgroup events to the correct CPU context to prevent a
     potential list double add

   - Prevent an integer underflow in the perf mlock accounting

   - Add a missing prototype for arch_perf_update_userpage()

  Tooling:

   - Add a missing unlock in the error path of maps__insert() in perf
     maps.

   - Fix the build with the latest libbfd

   - Fix the perf parser so it does not delete parse event terms, which
     caused a regression for using perf with the ARM CoreSight as the
     sink configuration was missing due to the deletion.

   - Fix the double free in the perf CPU map merging test case

   - Add the missing ustring support for the perf probe command"

* tag 'perf-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf maps: Add missing unlock to maps__insert() error case
  perf probe: Add ustring support for perf probe command
  perf: Make perf able to build with latest libbfd
  perf test: Fix test case Merge cpu map
  perf parse: Copy string to perf_evsel_config_term
  perf parse: Refactor 'struct perf_evsel_config_term'
  kernel/events: Add a missing prototype for arch_perf_update_userpage()
  perf/cgroups: Install cgroup events to correct cpuctx
  perf/core: Fix mlock accounting in perf_mmap()

Pull timer fixes from Thomas Gleixner:
 "Two small fixes for the time(r) subsystem:

   - Handle a subtle race between the clocksource watchdog and a
     concurrent clocksource watchdog stop/start sequence correctly to
     prevent a timer double add bug.

   - Fix the file path for the core time namespace file"

* tag 'timers-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: Prevent double add_timer_on() for watchdog_timer
  MAINTAINERS: Correct path to time namespace source file

Pull interrupt fixes from Thomas Gleixner:
 "A set of fixes for the interrupt subsystem:

   - Provision only ACPI enabled redistributors on GICv3

   - Use the proper command colums when building the INVALL command for
     the GICv3-ITS

   - Ensure the allocation of the L2 vPE table for GICv4.1

   - Correct the GICv4.1 VPROBASER programming so it uses the proper
     size

   - A set of small GICv4.1 tidy up patches

   - Configuration cleanup for C-SKY interrupt chip

   - Clarify the function documentation for irq_set_wake() to document
     that the wakeup functionality is orthogonal to the irq
     disable/enable mechanism"

* tag 'irq-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic-v3-its: Rename VPENDBASER/VPROPBASER accessors
  irqchip/gic-v3-its: Remove superfluous WARN_ON
  irqchip/gic-v4.1: Drop 'tmp' in inherit_vpe_l1_table_from_rd()
  irqchip/gic-v4.1: Ensure L2 vPE table is allocated at RD level
  irqchip/gic-v4.1: Set vpe_l1_base for all redistributors
  irqchip/gic-v4.1: Fix programming of GICR_VPROPBASER_4_1_SIZE
  genirq: Clarify that irq wake state is orthogonal to enable/disable
  irqchip/gic-v3-its: Reference to its_invall_cmd descriptor when building INVALL
  irqchip: Some Kconfig cleanup for C-SKY
  irqchip/gic-v3: Only provision redistributors that are enabled in ACPI

Pull EFI fix from Thomas Gleixner:
 "A single fix for a EFI boot regression on X86 which was caused by the
  recent rework of the EFI memory map parsing. On systems with invalid
  memmap entries the cleanup function uses an value which cannot be
  relied on in this stage. Use the actual EFI memmap entry instead"

* tag 'efi-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/x86: Fix boot regression on systems with invalid memmap entries

Pull misc SCSI fixes from James Bottomley:
 "Five small patches, all in drivers or doc, which missed the initial
  pull request.

  The qla2xxx and megaraid_sas are actual fixes and the rest are
  spelling and doc changes"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: ufs: fix spelling mistake "initilized" -> "initialized"
  scsi: pm80xx: fix spelling mistake "to" -> "too"
  scsi: MAINTAINERS: ufs: remove pedrom.sousa@synopsys.com
  scsi: megaraid_sas: fixup MSIx interrupt setup during resume
  scsi: qla2xxx: Fix unbound NVME response length

Pull networking fixes from David Miller:

 1) Unbalanced locking in mwifiex_process_country_ie, from Brian Norris.

 2) Fix thermal zone registration in iwlwifi, from Andrei
    Otcheretianski.

 3) Fix double free_irq in sgi ioc3 eth, from Thomas Bogendoerfer.

 4) Use after free in mptcp, from Florian Westphal.

 5) Use after free in wireguard's root_remove_peer_lists, from Eric
    Dumazet.

 6) Properly access packets heads in bonding alb code, from Eric
    Dumazet.

 7) Fix data race in skb_queue_len(), from Qian Cai.

 8) Fix regression in r8169 on some chips, from Heiner Kallweit.

 9) Fix XDP program ref counting in hv_netvsc, from Haiyang Zhang.

10) Certain kinds of set link netlink operations can cause a NULL deref
    in the ipv6 addrconf code. Fix from Eric Dumazet.

11) Don't cancel uninitialized work queue in drop monitor, from Ido
    Schimmel.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (84 commits)
  net: thunderx: use proper interface type for RGMII
  mt76: mt7615: fix max_nss in mt7615_eeprom_parse_hw_cap
  bpf: Improve bucket_log calculation logic
  selftests/bpf: Test freeing sockmap/sockhash with a socket in it
  bpf, sockhash: Synchronize_rcu before free'ing map
  bpf, sockmap: Don't sleep while holding RCU lock on tear-down
  bpftool: Don't crash on missing xlated program instructions
  bpf, sockmap: Check update requirements after locking
  drop_monitor: Do not cancel uninitialized work item
  mlxsw: spectrum_dpipe: Add missing error path
  mlxsw: core: Add validation of hardware device types for MGPIR register
  mlxsw: spectrum_router: Clear offload indication from IPv6 nexthops on abort
  selftests: mlxsw: Add test cases for local table route replacement
  mlxsw: spectrum_router: Prevent incorrect replacement of local table routes
  net: dsa: microchip: enable module autoprobe
  ipv6/addrconf: fix potential NULL deref in inet6_set_link_af()
  dpaa_eth: support all modes with rate adapting PHYs
  net: stmmac: update pci platform data to use phy_interface
  net: stmmac: xgmac: fix missing IFF_MULTICAST checki in dwxgmac2_set_filter
  net: stmmac: fix missing IFF_MULTICAST check in dwmac4_set_filter
  ...

VirtualBox hosts can share folders with guests, this commit adds a
VFS driver implementing the Linux-guest side of this, allowing folders
exported by the host to be mounted under Linux.

This driver depends on the guest <-> host IPC functions exported by
the vboxguest driver.
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Pull powerpc fixes from Michael Ellerman:

 - Fix an existing bug in our user access handling, exposed by one of
   the bug fixes we merged this cycle.

 - A fix for a boot hang on 32-bit with CONFIG_TRACE_IRQFLAGS and the
   recently added CONFIG_VMAP_STACK.

Thanks to: Christophe Leroy, Guenter Roeck.

* tag 'powerpc-5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc: Fix CONFIG_TRACE_IRQFLAGS with CONFIG_VMAP_STACK
  powerpc/futex: Fix incorrect user access blocking

This is a merge error on my part - the driver was merged into mainline
by commit c5951e7c ("Merge tag 'mips_5.6' of git://../mips/linux")
over a week ago, but nobody apparently noticed that it didn't actually
build due to still having a reference to the devm_ioremap_nocache()
function, removed a few days earlier through commit 6a1000bd ("Merge
tag 'ioremap-5.6' of git://../ioremap").

Apparently this didn't get any build testing anywhere.  Not perhaps all
that surprising: it's restricted to 64-bit MIPS only, and only with the
new SGI_MFD_IOC3 support enabled.

I only noticed because the ioremap conflicts in the ARM SoC driver
update made me check there weren't any others hiding, and I found this
one.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull ARM SoC late updates from Olof Johansson:
 "This is some material that we picked up into our tree late, or that
  had more complex dependencies on more than one topic branch that makes
  sense to keep separately.

   - TI support for secure accelerators and hwrng on OMAP4/5

   - TI camera changes for dra7 and am437x and SGX improvement due to
     better reset control support on am335x, am437x and dra7

   - Davinci moves to proper clocksource on DM365, and regulator/audio
     improvements for DM365 and DM644x eval boards"

* tag 'armsoc-late' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (32 commits)
  ARM: dts: omap4-droid4: Enable hdq for droid4 ds250x 1-wire battery nvmem
  ARM: dts: motorola-cpcap-mapphone: Configure calibration interrupt
  ARM: dts: Configure interconnect target module for am437x sgx
  ARM: dts: Configure sgx for dra7
  ARM: dts: Configure rstctrl reset for am335x SGX
  ARM: dts: dra7: Add ti-sysc node for VPE
  ARM: dts: dra7: add vpe clkctrl node
  ARM: dts: am43x-epos-evm: Add VPFE and OV2659 entries
  ARM: dts: am437x-sk-evm: Add VPFE and OV2659 entries
  ARM: dts: am43xx: add support for clkout1 clock
  arm: dts: dra76-evm: Add CAL and OV5640 nodes
  arm: dtsi: dra76x: Add CAL dtsi node
  arm: dts: dra72-evm-common: Add entries for the CSI2 cameras
  ARM: dts: DRA72: Add CAL dtsi node
  ARM: dts: dra7-l4: Add ti-sysc node for CAM
  ARM: OMAP: DRA7xx: Make CAM clock domain SWSUP only
  ARM: dts: dra7: add cam clkctrl node
  ARM: OMAP2+: Drop legacy platform data for omap4 des
  ARM: OMAP2+: Drop legacy platform data for omap4 sham
  ARM: OMAP2+: Drop legacy platform data for omap4 aes
  ...

Pull ARM SoC defconfig updates from Olof Johansson:
 "We keep this in a separate branch to avoid cross-branch conflicts, but
  most of the material here is fairly boring -- some new drivers turned
  on for hardware since they were merged, and some refreshed files due
  to time having moved a lot of entries around"

* tag 'armsoc-defconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (38 commits)
  ARM: configs: at91: enable MMC_SDHCI_OF_AT91 and MICROCHIP_PIT64B
  arm64: defconfig: Enable Broadcom's GENET Ethernet controller
  ARM: multi_v7_defconfig: Enable devfreq thermal integration
  ARM: exynos_defconfig: Enable devfreq thermal integration
  ARM: multi_v7_defconfig: Enable NFS v4.1 and v4.2
  ARM: exynos_defconfig: Enable NFS v4.1 and v4.2
  arm64: defconfig: Enable Actions Semi specific drivers
  arm64: defconfig: Enable Broadcom's STB PCIe controller
  arm64: defconfig: Enable CONFIG_CLK_IMX8MP by default
  ARM: configs: at91: enable config flags for sam9x60 SoC
  ARM: configs: at91: use savedefconfig
  arm64: defconfig: Enable tegra XUDC support
  ARM: defconfig: gemini: Update defconfig
  arm64: defconfig: enable CONFIG_ARM_QCOM_CPUFREQ_NVMEM
  arm64: defconfig: enable CONFIG_QCOM_CPR
  arm64: defconfig: Enable HFPLL
  arm64: defconfig: Enable CRYPTO_DEV_FSL_CAAM
  ARM: imx_v6_v7_defconfig: Select the TFP410 driver
  ARM: imx_v6_v7_defconfig: Enable NFS_V4_1 and NFS_V4_2 support
  arm64: defconfig: Enable ATH10K_SNOC
  ...

Pull ARM SoC-related driver updates from Olof Johansson:
 "Various driver updates for platforms:

   - Nvidia: Fuse support for Tegra194, continued memory controller
     pieces for Tegra30

   - NXP/FSL: Refactorings of QuickEngine drivers to support
     ARM/ARM64/PPC

   - NXP/FSL: i.MX8MP SoC driver pieces

   - TI Keystone: ring accelerator driver

   - Qualcomm: SCM driver cleanup/refactoring + support for new SoCs.

   - Xilinx ZynqMP: feature checking interface for firmware. Mailbox
     communication for power management

   - Overall support patch set for cpuidle on more complex hierarchies
     (PSCI-based)

  and misc cleanups, refactorings of Marvell, TI, other platforms"

* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (166 commits)
  drivers: soc: xilinx: Use mailbox IPI callback
  dt-bindings: power: reset: xilinx: Add bindings for ipi mailbox
  drivers: soc: ti: knav_qmss_queue: Pass lockdep expression to RCU lists
  MAINTAINERS: Add brcmstb PCIe controller entry
  soc/tegra: fuse: Unmap registers once they are not needed anymore
  soc/tegra: fuse: Correct straps' address for older Tegra124 device trees
  soc/tegra: fuse: Warn if straps are not ready
  soc/tegra: fuse: Cache values of straps and Chip ID registers
  memory: tegra30-emc: Correct error message for timed out auto calibration
  memory: tegra30-emc: Firm up hardware programming sequence
  memory: tegra30-emc: Firm up suspend/resume sequence
  soc/tegra: regulators: Do nothing if voltage is unchanged
  memory: tegra: Correct reset value of xusb_hostr
  soc/tegra: fuse: Add APB DMA dependency for Tegra20
  bus: tegra-aconnect: Remove PM_CLK dependency
  dt-bindings: mediatek: add MT6765 power dt-bindings
  soc: mediatek: cmdq: delete not used define
  memory: tegra: Add support for the Tegra194 memory controller
  memory: tegra: Only include support for enabled SoCs
  memory: tegra: Support DVFS on Tegra186 and later
  ...

Pull ARM Device-tree updates from Olof Johansson:
 "New SoCs:

   - Atmel/Microchip SAM9X60 (ARM926 SoC)

   - OMAP 37xx gets split into AM3703/AM3715/DM3725, who are all
     variants of it with different GPU/media IP configurations.

   - ST stm32mp15 SoCs (1-2 Cortex-A7, CAN, GPU depending on SKU)

   - ST Ericsson ab8505 (variant of ab8500) and db8520 (variant of
     db8500)

   - Unisoc SC9863A SoC (8x Cortex-A55 mobile chipset w/ GPU, modem)

   - Qualcomm SC7180 (8-core 64bit SoC, unnamed CPU class)

  New boards:

   - Allwinner:
      + Emlid Neutis SoM (H3 variant)
      + Libre Computer ALL-H3-IT
      + PineH64 Model B

   - Amlogic:
      + Libretech Amlogic GX PC (s905d and s912-based variants)

   - Atmel/Microchip:
      + Kizboxmini, sam9x60 EK, sama5d27 Wireless SOM (wlsom1)

   - Marvell:
      + Armada 385-based SolidRun Clearfog GTR

   - NXP:
      + Gateworks GW59xx boards based on i.MX6/6Q/6QDL
      + Tolino Shine 3 eBook reader (i.MX6sl)
      + Embedded Artists COM (i.MX7ULP)
      + SolidRun CLearfog CX/ITX and HoneyComb (LX2160A-based systems)
      + Google Coral Edge TPU (i.MX8MQ)

   - Rockchip:
      + Radxa Dalang Carrier (supports rk3288 and rk3399 SOMs)
      + Radxa Rock Pi N10 (RK3399Pro-based)
      + VMARC RK3399Pro SOM

   - ST:
      + Reference boards for stm32mp15

   - ST Ericsson:
      + Samsung Galaxy S III mini (GT-I8190)
      + HREF520 reference board for DB8520

   - TI OMAP:
      + Gen1 Amazon Echo (OMAP3630-based)

   - Qualcomm:
      + Inforce 6640 Single Board Computer (msm8996-based)
      + SC7180 IDP (SC7180-based)"

* tag 'armsoc-dt' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (623 commits)
  dt-bindings: fix compilation error of the example in marvell,mmp3-hsic-phy.yaml
  arm64: dts: ti: k3-am654-base-board: Add CSI2 OV5640 camera
  arm64: dts: ti: k3-am65-main Add CAL node
  arm64: dts: ti: k3-j721e-main: Add McASP nodes
  arm64: dts: ti: k3-am654-main: Add McASP nodes
  arm64: dts: ti: k3-j721e: DMA support
  arm64: dts: ti: k3-j721e-main: Move secure proxy and smmu under main_navss
  arm64: dts: ti: k3-j721e-main: Correct main NAVSS representation
  arm64: dts: ti: k3-j721e: Correct the address for MAIN NAVSS
  arm64: dts: ti: k3-am65: DMA support
  arm64: dts: ti: k3-am65-main: Move secure proxy under cbass_main_navss
  arm64: dts: ti: k3-am65-main: Correct main NAVSS representation
  ARM: dts: aspeed: rainier: Add UCD90320 power sequencer
  ARM: dts: aspeed: rainier: Switch PSUs to unknown version
  arm64: dts: rockchip: Kill off "simple-panel" compatibles
  ARM: dts: rockchip: Kill off "simple-panel" compatibles
  arm64: dts: rockchip: rename dwmmc node names to mmc
  ARM: dts: rockchip: rename dwmmc node names to mmc
  arm64: dts: exynos: Rename Samsung and Exynos to lowercase
  arm64: dts: uniphier: add reset-names to NAND controller node
  ...

Pull ARM SoC platform updates from Olof Johansson:
 "Most of these are smaller fixes that have accrued, and some continued
  cleanup of OMAP platforms towards shared frameworks.

  One new SoC from Atmel/Microchip: sam9x60"

* tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (35 commits)
  ARM: OMAP2+: Fix undefined reference to omap_secure_init
  ARM: s3c64xx: Drop unneeded select of TIMER_OF
  ARM: exynos: Drop unneeded select of MIGHT_HAVE_CACHE_L2X0
  ARM: s3c24xx: Switch to atomic pwm API in rx1950
  ARM: OMAP2+: sleep43xx: Call secure suspend/resume handlers
  ARM: OMAP2+: Use ARM SMC Calling Convention when OP-TEE is available
  ARM: OMAP2+: Introduce check for OP-TEE in omap_secure_init()
  ARM: OMAP2+: Add omap_secure_init callback hook for secure initialization
  ARM: at91: Documentation: add sam9x60 product and datasheet
  ARM: at91: pm: use of_device_id array to find the proper shdwc node
  ARM: at91: pm: use SAM9X60 PMC's compatible
  ARM: imx: only select ARM_ERRATA_814220 for ARMv7-A
  ARM: zynq: use physical cpuid in zynq_slcr_cpu_stop/start
  ARM: tegra: Use clk_m CPU on Tegra124 LP1 resume
  ARM: tegra: Modify reshift divider during LP1
  ARM: tegra: Enable PLLP bypass during Tegra124 LP1
  ARM: samsung: Rename Samsung and Exynos to lowercase
  ARM: exynos: Correct the help text for platform Kconfig option
  ARM: bcm: Select ARM_AMBA for ARCH_BRCMSTB
  ARM: brcmstb: Add debug UART entry for 7216
  ...

Pull compat-ioctl fix from Arnd Bergmann:
 "One patch in the compat-ioctl series broke 32-bit rootfs for multiple
  people testing on 64-bit kernels. Let's fix it in -rc1 before others
  run into the same issue"

* tag 'compat-ioctl-fix' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground:
  compat_ioctl: fix FIONREAD on devices

Pull vfs file system parameter updates from Al Viro:
 "Saner fs_parser.c guts and data structures. The system-wide registry
  of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is
  the horror switch() in fs_parse() that would have to grow another case
  every time something got added to that system-wide registry.

  New syntax types can be added by filesystems easily now, and their
  namespace is that of functions - not of system-wide enum members. IOW,
  they can be shared or kept private and if some turn out to be widely
  useful, we can make them common library helpers, etc., without having
  to do anything whatsoever to fs_parse() itself.

  And we already get that kind of requests - the thing that finally
  pushed me into doing that was "oh, and let's add one for timeouts -
  things like 15s or 2h". If some filesystem really wants that, let them
  do it. Without somebody having to play gatekeeper for the variants
  blessed by direct support in fs_parse(), TYVM.

  Quite a bit of boilerplate is gone. And IMO the data structures make a
  lot more sense now. -200LoC, while we are at it"

* 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits)
  tmpfs: switch to use of invalfc()
  cgroup1: switch to use of errorfc() et.al.
  procfs: switch to use of invalfc()
  hugetlbfs: switch to use of invalfc()
  cramfs: switch to use of errofc() et.al.
  gfs2: switch to use of errorfc() et.al.
  fuse: switch to use errorfc() et.al.
  ceph: use errorfc() and friends instead of spelling the prefix out
  prefix-handling analogues of errorf() and friends
  turn fs_param_is_... into functions
  fs_parse: handle optional arguments sanely
  fs_parse: fold fs_parameter_desc/fs_parameter_spec
  fs_parser: remove fs_parameter_description name field
  add prefix to fs_context->log
  ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log
  new primitive: __fs_parse()
  switch rbd and libceph to p_log-based primitives
  struct p_log, variants of warnf() et.al. taking that one instead
  teach logfc() to handle prefices, give it saner calling conventions
  get rid of cg_invalf()
  ...

Pull misc vfs updates from Al Viro:

 - bmap series from cmaiolino

 - getting rid of convolutions in copy_mount_options() (use a couple of
   copy_from_user() instead of the __get_user() crap)

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  saner copy_mount_options()
  fibmap: Reject negative block numbers
  fibmap: Use bmap instead of ->bmap method in ioctl_fibmap
  ecryptfs: drop direct calls to ->bmap
  cachefiles: drop direct usage of ->bmap method.
  fs: Enable bmap() function to properly return errors

Merge thundering herd avoidance on pipe IO.

This would have been applied for 5.5 already, but got delayed because of
a user-space race condition in the GNU make jobserver code.  Now that
there's a new GNU make 4.3 release, and most distributions seem to have
at least applied the (almost three year old) fix for the problem, let's
see if people notice.

And it might have been just bad random timing luck on my machine.

If you do hit the race condition, things will still work, but the
symptom is that you don't get nearly the expected parallelism when using
"make -j<N>".

The jobserver bug can definitely happen without this patch too, but
seems to be easier to trigger when we no longer wake up pipe waiters
unnecessarily.

* pipe-exclusive-wakeup:
  pipe: use exclusive waits when reading or writing

This makes the pipe code use separate wait-queues and exclusive waiting
for readers and writers, avoiding a nasty thundering herd problem when
there are lots of readers waiting for data on a pipe (or, less commonly,
lots of writers waiting for a pipe to have space).

While this isn't a common occurrence in the traditional "use a pipe as a
data transport" case, where you typically only have a single reader and
a single writer process, there is one common special case: using a pipe
as a source of "locking tokens" rather than for data communication.

In particular, the GNU make jobserver code ends up using a pipe as a way
to limit parallelism, where each job consumes a token by reading a byte
from the jobserver pipe, and releases the token by writing a byte back
to the pipe.

This pattern is fairly traditional on Unix, and works very well, but
will waste a lot of time waking up a lot of processes when only a single
reader needs to be woken up when a writer releases a new token.

A simplified test-case of just this pipe interaction is to create 64
processes, and then pass a single token around between them (this
test-case also intentionally passes another token that gets ignored to
test the "wake up next" logic too, in case anybody wonders about it):

    #include <unistd.h>

    int main(int argc, char **argv)
    {
        int fd[2], counters[2];

        pipe(fd);
        counters[0] = 0;
        counters[1] = -1;
        write(fd[1], counters, sizeof(counters));

        /* 64 processes */
        fork(); fork(); fork(); fork(); fork(); fork();

        do {
                int i;
                read(fd[0], &i, sizeof(i));
                if (i < 0)
                        continue;
                counters[0] = i+1;
                write(fd[1], counters, (1+(i & 1)) *sizeof(int));
        } while (counters[0] < 1000000);
        return 0;
    }

and in a perfect world, passing that token around should only cause one
context switch per transfer, when the writer of a token causes a
directed wakeup of just a single reader.

But with the "writer wakes all readers" model we traditionally had, on
my test box the above case causes more than an order of magnitude more
scheduling: instead of the expected ~1M context switches, "perf stat"
shows

        231,852.37 msec task-clock                #   15.857 CPUs utilized
        11,250,961      context-switches          #    0.049 M/sec
           616,304      cpu-migrations            #    0.003 M/sec
             1,648      page-faults               #    0.007 K/sec
 1,097,903,998,514      cycles                    #    4.735 GHz
   120,781,778,352      instructions              #    0.11  insn per cycle
    27,997,056,043      branches                  #  120.754 M/sec
       283,581,233      branch-misses             #    1.01% of all branches

      14.621273891 seconds time elapsed

       0.018243000 seconds user
       3.611468000 seconds sys

before this commit.

After this commit, I get

          5,229.55 msec task-clock                #    3.072 CPUs utilized
         1,212,233      context-switches          #    0.232 M/sec
           103,951      cpu-migrations            #    0.020 M/sec
             1,328      page-faults               #    0.254 K/sec
    21,307,456,166      cycles                    #    4.074 GHz
    12,947,819,999      instructions              #    0.61  insn per cycle
     2,881,985,678      branches                  #  551.096 M/sec
        64,267,015      branch-misses             #    2.23% of all branches

       1.702148350 seconds time elapsed

       0.004868000 seconds user
       0.110786000 seconds sys

instead. Much better.

[ Note! This kernel improvement seems to be very good at triggering a
  race condition in the make jobserver (in GNU make 4.2.1) for me. It's
  a long known bug that was fixed back in June 2017 by GNU make commit
  b552b0525198 ("[SV 51159] Use a non-blocking read with pselect to
  avoid hangs.").

  But there wasn't a new release of GNU make until 4.3 on Jan 19 2020,
  so a number of distributions may still have the buggy version. Some
  have backported the fix to their 4.2.1 release, though, and even
  without the fix it's quite timing-dependent whether the bug actually
  is hit. ]

Josh Triplett says:
 "I've been hammering on your pipe fix patch (switching to exclusive
  wait queues) for a month or so, on several different systems, and I've
  run into no issues with it. The patch *substantially* improves
  parallel build times on large (~100 CPU) systems, both with parallel
  make and with other things that use make's pipe-based jobserver.

  All current distributions (including stable and long-term stable
  distributions) have versions of GNU make that no longer have the
  jobserver bug"
Tested-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

My final cleanup patch for sys_compat_ioctl() introduced a regression on
the FIONREAD ioctl command, which is used for both regular and special
files, but only works on regular files after my patch, as I had missed
the warning that Al Viro put into a comment right above it.

Change it back so it can work on any file again by moving the implementation
to do_vfs_ioctl() instead.

Fixes: 77b90401 ("compat_ioctl: simplify the implementation")
Reported-and-tested-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Reported-and-tested-by: youling257 <youling257@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Merge tag 'irqchip-fixes-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent

Pull irqchip fixes for 5.6, take #1 from Marc Zyngier:

 - Guarantee allocation of L2 vPE table for GICv4.1
 - Fix GICv4.1 VPROPBASER programming
 - Numerous GICv4.1 tidy ups
 - Fix disabled GICv3 redistributor provisioning with ACPI
 - KConfig cleanup for C-SKY