Wen Yang <wen.yang99@zte.com.cn> and majiang <ma.jiang@zte.com.cn>
report that a periodic signal received during fork can cause fork to
continually restart preventing an application from making progress.

The code was being overly pessimistic.  Fork needs to guarantee that a
signal sent to multiple processes is logically delivered before the
fork and just to the forking process or logically delivered after the
fork to both the forking process and it's newly spawned child.  For
signals like periodic timers that are always delivered to a single
process fork can safely complete and let them appear to logically
delivered after the fork().

While examining this issue I also discovered that fork today will miss
signals delivered to multiple processes during the fork and handled by
another thread.  Similarly the current code will also miss blocked
signals that are delivered to multiple process, as those signals will
not appear pending during fork.

Add a list of each thread that is currently forking, and keep on that
list a signal set that records all of the signals sent to multiple
processes.  When fork completes initialize the new processes
shared_pending signal set with it.  The calculate_sigpending function
will see those signals and set TIF_SIGPENDING causing the new task to
take the slow path to userspace to handle those signals.  Making it
appear as if those signals were received immediately after the fork.

It is not possible to send real time signals to multiple processes and
exceptions don't go to multiple processes, which means that that are
no signals sent to multiple processes that require siginfo.  This
means it is safe to not bother collecting siginfo on signals sent
during fork.

The sigaction of a child of fork is initially the same as the
sigaction of the parent process.  So a signal the parent ignores the
child will also initially ignore.  Therefore it is safe to ignore
signals sent to multiple processes and ignored by the forking process.

Signals sent to only a single process or only a single thread and delivered
during fork are treated as if they are received after the fork, and generally
not dealt with.  They won't cause any problems.

V2: Added removal from the multiprocess list on failure.
V3: Use -ERESTARTNOINTR directly
V4: - Don't queue both SIGCONT and SIGSTOP
    - Initialize signal_struct.multiprocess in init_task
    - Move setting of shared_pending to before the new task
      is visible to signals.  This prevents signals from comming
      in before shared_pending.signal is set to delayed.signal
      and being lost.
V5: - rework list add and delete to account for idle threads
v6: - Use sigdelsetmask when removing stop signals

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200447
Reported-by: Wen Yang <wen.yang99@zte.com.cn> and
Reported-by: majiang <ma.jiang@zte.com.cn>
Fixes: 4a2c7a78 ("[PATCH] make fork() atomic wrt pgrp/session signals")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

There are only two signals that are delivered to every member of a
signal group: SIGSTOP and SIGKILL.  Signal delivery requires every
signal appear to be delivered either before or after a clone syscall.
SIGKILL terminates the clone so does not need to be considered.  Which
leaves only SIGSTOP that needs to be considered when creating new
threads.

Today in the event of a group stop TIF_SIGPENDING will get set and the
fork will restart ensuring the fork syscall participates in the group
stop.

A fork (especially of a process with a lot of memory) is one of the
most expensive system so we really only want to restart a fork when
necessary.

It is easy so check to see if a SIGSTOP is ongoing and have the new
thread join it immediate after the clone completes.  Making it appear
the clone completed happened just before the SIGSTOP.

The calculate_sigpending function will see the bits set in jobctl and
set TIF_SIGPENDING to ensure the new task takes the slow path to userspace.

V2: The call to task_join_group_stop was moved before the new task is
    added to the thread group list.  This should not matter as
    sighand->siglock is held over both the addition of the threads,
    the call to task_join_group_stop and do_signal_stop.  But the change
    is trivial and it is one less thing to worry about when reading
    the code.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

The code in calculate_sigpending will now handle this so
it is just redundant and possibly a little confusing
to continue setting TIF_SIGPENDING in ptrace_init_task.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Add a function calculate_sigpending to test to see if any signals are
pending for a new task immediately following fork.  Signals have to
happen either before or after fork.  Today our practice is to push
all of the signals to before the fork, but that has the downside that
frequent or periodic signals can make fork take much much longer than
normal or prevent fork from completing entirely.

So we need move signals that we can after the fork to prevent that.

This updates the code to set TIF_SIGPENDING on a new task if there
are signals or other activities that have moved so that they appear
to happen after the fork.

As the code today restarts if it sees any such activity this won't
immediately have an effect, as there will be no reason for it
to set TIF_SIGPENDING immediately after the fork.

Adding calculate_sigpending means the code in fork can safely be
changed to not always restart if a signal is pending.

The new calculate_sigpending function sets sigpending if there
are pending bits in jobctl, pending signals, the freezer needs
to freeze the new task or the live kernel patching framework
need the new thread to take the slow path to userspace.

I have verified that setting TIF_SIGPENDING does make a new process
take the slow path to userspace before it executes it's first userspace
instruction.

I have looked at the callers of signal_wake_up and the code paths
setting TIF_SIGPENDING and I don't see anything else that needs to be
handled.  The code probably doesn't need to set TIF_SIGPENDING for the
kernel live patching as it uses a separate thread flag as well.  But
at this point it seems safer reuse the recalc_sigpending logic and get
the kernel live patching folks to sort out their story later.

V2: I have moved the test into schedule_tail where siglock can
    be grabbed and recalc_sigpending can be reused directly.
    Further as the last action of setting up a new task this
    guarantees that TIF_SIGPENDING will be properly set in the
    new process.

    The helper calculate_sigpending takes the siglock and
    uncontitionally sets TIF_SIGPENDING and let's recalc_sigpending
    clear TIF_SIGPENDING if it is unnecessary.  This allows reusing
    the existing code and keeps maintenance of the conditions simple.

    Oleg Nesterov <oleg@redhat.com>  suggested the movement
    and pointed out the need to take siglock if this code
    was going to be called while the new task is discoverable.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

In practice this does not change anything as testing for fatal_signal_pending
and exiting for with an error code duplicates the work of the next clause
which recalculates pending signals and then exits fork if any are pending.
In both cases the pending signal will trigger the slow path when existing
to userspace, and the fatal signal will cause do_exit to be called.

The advantage of making this a separate test is that it makes it clear
processing the fatal signal will terminate the fork, and it allows the
rest of the signal logic to be updated without fear that this important
case will be lost.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Normally this would be something that would be handled by handling
signals that are sent to a group of processes but in this case the
forking process is not a member of the group being signaled.  Thus
special code is needed to prevent a race with pid namespaces exiting,
and fork adding new processes within them.

Move this test up before the signal restart just in case signals are
also pending.  Fatal conditions should take presedence over restarts.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

This is the bottom and by pushing this down it simplifies the callers
and otherwise leaves things as is.  This is in preparation for allowing
fork to implement better handling of signals set to groups of processes.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

This information is already available in the callers and by pushing it
down it makes the code a little clearer, and allows implementing
better handling of signales set to a group of processes in fork.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

This information is already available in the callers and by pushing it
down it makes the code a little clearer, and allows better group
signal behavior in fork.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

This passes the information we already have at the call sight into
do_send_sig_info.  Ultimately allowing for better handling of signals
sent to a group of processes during fork.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

This information is already present and using it directly simplifies the logic
of the code.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

This passes the information we already have at the call sight
into group_send_sig_info.  Ultimatelly allowing for to better handle
signals sent to a group of processes.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Make the code more maintainable by performing more of the signal
related work in send_sigqueue.

A quick inspection of do_timer_create will show that this code path
does not lookup a thread group by a thread's pid.  Making it safe
to find the task pointed to by it_pid with "pid_task(it_pid, type)";

This supports the changes needed in fork to tell if a signal was sent
to a single process or a group of processes.

Having the pid to task transition in signal.c will also make it easier
to sort out races with de_thread and and the thread group leader
exiting when it comes time to address that.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

In good_sigevent directly compute the default return value as
"task_tgid(current)".  This is exactly the same as
"task_pid(current->group_leader)" but written more clearly.

In the thread case first compute the thread's pid.  Then veify that
attached to that pid is a thread of the current thread group.

This has the net effect of making the code a little clearer, and
making it obvious that posix timers never look up a process by a the
pid of a thread.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

When f_setown is called a pid and a pid type are stored.  Replace the use
of PIDTYPE_PID with PIDTYPE_TGID as PIDTYPE_TGID goes to the entire thread
group.  Replace the use of PIDTYPE_MAX with PIDTYPE_PID as PIDTYPE_PID now
is only for a thread.

Update the users of __f_setown to use PIDTYPE_TGID instead of
PIDTYPE_PID.

For now the code continues to capture task_pid (when task_tgid would
really be appropriate), and iterate on PIDTYPE_PID (even when type ==
PIDTYPE_TGID) out of an abundance of caution to preserve existing
behavior.

Oleg Nesterov suggested using the test to ensure we use PIDTYPE_PID
for tgid lookup also be used to avoid taking the tasklist lock.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Everywhere except in the pid array we distinguish between a tasks pid and
a tasks tgid (thread group id).  Even in the enumeration we want that
distinction sometimes so we have added __PIDTYPE_TGID.  With leader_pid
we almost have an implementation of PIDTYPE_TGID in struct signal_struct.

Add PIDTYPE_TGID as a first class member of the pid_type enumeration and
into the pids array.  Then remove the __PIDTYPE_TGID special case and the
leader_pid in signal_struct.

The net size increase is just an extra pointer added to struct pid and
an extra pair of pointers of an hlist_node added to task_struct.

The effect on code maintenance is the removal of a number of special
cases today and the potential to remove many more special cases as
PIDTYPE_TGID gets used to it's fullest.  The long term potential
is allowing zombie thread group leaders to exit, which will remove
a lot more special cases in the code.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

To access these fields the code always has to go to group leader so
going to signal struct is no loss and is actually a fundamental simplification.

This saves a little bit of memory by only allocating the pid pointer array
once instead of once for every thread, and even better this removes a
few potential races caused by the fact that group_leader can be changed
by de_thread, while signal_struct can not.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

The cost is the the same and this removes the need
to worry about complications that come from de_thread
and group_leader changing.

__task_pid_nr_ns has been updated to take advantage of this change.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

The function is general and inline so there is no need
to hide it inside of exit.c
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

This is cheap and no cost so we might as well.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Pull block fixes from Jens Axboe:
 "A collection of fixes that should go into -rc1. This contains:

   - bsg_open vs bsg_unregister race fix (Anatoliy)

   - NVMe pull request from Christoph, with fixes for regressions in
     this window, FC connect/reconnect path code unification, and a
     trace point addition.

   - timeout fix (Christoph)

   - remove a few unused functions (Christoph)

   - blk-mq tag_set reinit fix (Roman)"

* tag 'for-linus-20180616' of git://git.kernel.dk/linux-block:
  bsg: fix race of bsg_open and bsg_unregister
  block: remov blk_queue_invalidate_tags
  nvme-fabrics: fix and refine state checks in __nvmf_check_ready
  nvme-fabrics: handle the admin-only case properly in nvmf_check_ready
  nvme-fabrics: refactor queue ready check
  blk-mq: remove blk_mq_tagset_iter
  nvme: remove nvme_reinit_tagset
  nvme-fc: fix nulling of queue data on reconnect
  nvme-fc: remove reinit_request routine
  blk-mq: don't time out requests again that are in the timeout handler
  nvme-fc: change controllers first connect to use reconnect path
  nvme: don't rely on the changed namespace list log
  nvmet: free smart-log buffer after use
  nvme-rdma: fix error flow during mapping request data
  nvme: add bio remapping tracepoint
  nvme: fix NULL pointer dereference in nvme_init_subsystem
  blk-mq: reinit q->tag_set_list entry only after grace period

Pull documentation fixes from Mauro Carvalho Chehab:
 "This solves a series of broken links for files under Documentation,
  and improves a script meant to detect such broken links (see
  scripts/documentation-file-ref-check).

  The changes on this series are:

   - can.rst: fix a footnote reference;

   - crypto_engine.rst: Fix two parsing warnings;

   - Fix a lot of broken references to Documentation/*;

   - improve the scripts/documentation-file-ref-check script, in order
     to help detecting/fixing broken references, preventing
     false-positives.

  After this patch series, only 33 broken references to doc files are
  detected by scripts/documentation-file-ref-check"

* tag 'docs-broken-links' of git://linuxtv.org/mchehab/experimental: (26 commits)
  fix a series of Documentation/ broken file name references
  Documentation: rstFlatTable.py: fix a broken reference
  ABI: sysfs-devices-system-cpu: remove a broken reference
  devicetree: fix a series of wrong file references
  devicetree: fix name of pinctrl-bindings.txt
  devicetree: fix some bindings file names
  MAINTAINERS: fix location of DT npcm files
  MAINTAINERS: fix location of some display DT bindings
  kernel-parameters.txt: fix pointers to sound parameters
  bindings: nvmem/zii: Fix location of nvmem.txt
  docs: Fix more broken references
  scripts/documentation-file-ref-check: check tools/*/Documentation
  scripts/documentation-file-ref-check: get rid of false-positives
  scripts/documentation-file-ref-check: hint: dash or underline
  scripts/documentation-file-ref-check: add a fix logic for DT
  scripts/documentation-file-ref-check: accept more wildcards at filenames
  scripts/documentation-file-ref-check: fix help message
  media: max2175: fix location of driver's companion documentation
  media: v4l: fix broken video4linux docs locations
  media: dvb: point to the location of the old README.dvb-usb file
  ...

Pull fsnotify updates from Jan Kara:
 "fsnotify cleanups unifying handling of different watch types.

  This is the shortened fsnotify series from Amir with the last five
  patches pulled out. Amir has modified those patches to not change
  struct inode but obviously it's too late for those to go into this
  merge window"

* tag 'fsnotify_for_v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fsnotify: add fsnotify_add_inode_mark() wrappers
  fanotify: generalize fanotify_should_send_event()
  fsnotify: generalize send_to_group()
  fsnotify: generalize iteration of marks by object type
  fsnotify: introduce marks iteration helpers
  fsnotify: remove redundant arguments to handle_event()
  fsnotify: use type id to identify connector object type

Pull fbdev updates from Bartlomiej Zolnierkiewicz:
 "There is nothing really major here, few small fixes, some cleanups and
  dead drivers removal:

   - mark omapfb drivers as orphans in MAINTAINERS file (Tomi Valkeinen)

   - add missing module license tags to omap/omapfb driver (Arnd
     Bergmann)

   - add missing GPIOLIB dependendy to omap2/omapfb driver (Arnd
     Bergmann)

   - convert savagefb, aty128fb & radeonfb drivers to use msleep & co.
     (Jia-Ju Bai)

   - allow COMPILE_TEST build for viafb driver (media part was reviewed
     by media subsystem Maintainer)

   - remove unused MERAM support from sh_mobile_lcdcfb and shmob-drm
     drivers (drm parts were acked by shmob-drm driver Maintainer)

   - remove unused auo_k190xfb drivers

   - misc cleanups (Souptick Joarder, Wolfram Sang, Markus Elfring, Andy
     Shevchenko, Colin Ian King)"

* tag 'fbdev-v4.18' of git://github.com/bzolnier/linux: (26 commits)
  fb_omap2: add gpiolib dependency
  video/omap: add module license tags
  MAINTAINERS: make omapfb orphan
  video: fbdev: pxafb: match_string() conversion fixup
  video: fbdev: nvidia: fix spelling mistake: "scaleing" -> "scaling"
  video: fbdev: fix spelling mistake: "frambuffer" -> "framebuffer"
  video: fbdev: pxafb: Convert to use match_string() helper
  video: fbdev: via: allow COMPILE_TEST build
  video: fbdev: remove unused sh_mobile_meram driver
  drm: shmobile: remove unused MERAM support
  video: fbdev: sh_mobile_lcdcfb: remove unused MERAM support
  video: fbdev: remove unused auo_k190xfb drivers
  video: omap: Improve a size determination in omapfb_do_probe()
  video: sm501fb: Improve a size determination in sm501fb_probe()
  video: fbdev-MMP: Improve a size determination in path_init()
  video: fbdev-MMP: Delete an error message for a failed memory allocation in two functions
  video: auo_k190x: Delete an error message for a failed memory allocation in auok190x_common_probe()
  video: sh_mobile_lcdcfb: Delete an error message for a failed memory allocation in two functions
  video: sh_mobile_meram: Delete an error message for a failed memory allocation in sh_mobile_meram_probe()
  video: fbdev: sh_mobile_meram: Drop SUPERH platform dependency
  ...

Pull AFS updates from Al Viro:
 "Assorted AFS stuff - ended up in vfs.git since most of that consists
  of David's AFS-related followups to Christoph's procfs series"

* 'afs-proc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  afs: Optimise callback breaking by not repeating volume lookup
  afs: Display manually added cells in dynamic root mount
  afs: Enable IPv6 DNS lookups
  afs: Show all of a server's addresses in /proc/fs/afs/servers
  afs: Handle CONFIG_PROC_FS=n
  proc: Make inline name size calculation automatic
  afs: Implement network namespacing
  afs: Mark afs_net::ws_cell as __rcu and set using rcu functions
  afs: Fix a Sparse warning in xdr_decode_AFSFetchStatus()
  proc: Add a way to make network proc files writable
  afs: Rearrange fs/afs/proc.c to remove remaining predeclarations.
  afs: Rearrange fs/afs/proc.c to move the show routines up
  afs: Rearrange fs/afs/proc.c by moving fops and open functions down
  afs: Move /proc management functions to the end of the file

Pull compat updates from Al Viro:
 "Some biarch patches - getting rid of assorted (mis)uses of
  compat_alloc_user_space().

  Not much in that area this cycle..."

* 'work.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  orangefs: simplify compat ioctl handling
  signalfd: lift sigmask copyin and size checks to callers of do_signalfd4()
  vmsplice(): lift importing iovec into vmsplice(2) and compat counterpart

Pull aio fixes from Al Viro:
 "Assorted AIO followups and fixes"

* 'work.aio' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  eventpoll: switch to ->poll_mask
  aio: only return events requested in poll_mask() for IOCB_CMD_POLL
  eventfd: only return events requested in poll_mask()
  aio: mark __aio_sigset::sigmask const

Pull networking fixes from David Miller:

 1) Various netfilter fixlets from Pablo and the netfilter team.

 2) Fix regression in IPVS caused by lack of PMTU exceptions on local
    routes in ipv6, from Julian Anastasov.

 3) Check pskb_trim_rcsum for failure in DSA, from Zhouyang Jia.

 4) Don't crash on poll in TLS, from Daniel Borkmann.

 5) Revert SO_REUSE{ADDR,PORT} change, it regresses various things
    including Avahi mDNS. From Bart Van Assche.

 6) Missing of_node_put in qcom/emac driver, from Yue Haibing.

 7) We lack checking of the TCP checking in one special case during SYN
    receive, from Frank van der Linden.

 8) Fix module init error paths of mac80211 hwsim, from Johannes Berg.

 9) Handle 802.1ad properly in stmmac driver, from Elad Nachman.

10) Must grab HW caps before doing quirk checks in stmmac driver, from
    Jose Abreu.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (81 commits)
  net: stmmac: Run HWIF Quirks after getting HW caps
  neighbour: skip NTF_EXT_LEARNED entries during forced gc
  net: cxgb3: add error handling for sysfs_create_group
  tls: fix waitall behavior in tls_sw_recvmsg
  tls: fix use-after-free in tls_push_record
  l2tp: filter out non-PPP sessions in pppol2tp_tunnel_ioctl()
  l2tp: reject creation of non-PPP sessions on L2TPv2 tunnels
  mlxsw: spectrum_switchdev: Fix port_vlan refcounting
  mlxsw: spectrum_router: Align with new route replace logic
  mlxsw: spectrum_router: Allow appending to dev-only routes
  ipv6: Only emit append events for appended routes
  stmmac: added support for 802.1ad vlan stripping
  cfg80211: fix rcu in cfg80211_unregister_wdev
  mac80211: Move up init of TXQs
  mac80211_hwsim: fix module init error paths
  cfg80211: initialize sinfo in cfg80211_get_station
  nl80211: fix some kernel doc tag mistakes
  hv_netvsc: Fix the variable sizes in ipsecv2 and rsc offload
  rds: avoid unenecessary cong_update in loop transport
  l2tp: clean up stale tunnel or session in pppol2tp_connect's error path
  ...

Pull module updates from Jessica Yu:
 "Minor code cleanup and also allow sig_enforce param to be shown in
  sysfs with CONFIG_MODULE_SIG_FORCE"

* tag 'modules-for-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: Allow to always show the status of modsign
  module: Do not access sig_enforce directly

Pull uml updates from Richard Weinberger:
 "Minor updates for UML:

   - fixes for our new vector network driver by Anton

   - initcall cleanup by Alexander

   - We have a new mailinglist, sourceforge.net sucks"

* 'for-linus-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: Fix raw interface options
  um: Fix initialization of vector queues
  um: remove uml initcalls
  um: Update mailing list address

Merge tag 'riscv-for-linus-4.18-merge_window' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux

Pull RISC-V updates from Palmer Dabbelt:
 "This contains some small RISC-V updates I'd like to target for 4.18.

  They are all fairly small this time. Here's a short summary, there's
  more info in the commits/merges:

   - a fix to __clear_user to respect the passed arguments.

   - enough support for the perf subsystem to work with RISC-V's ISA
     defined performance counters.

   - support for sparse and cleanups suggested by it.

   - support for R_RISCV_32 (a relocation, not the 32-bit ISA).

   - some MAINTAINERS cleanups.

   - the addition of CONFIG_HVC_RISCV_SBI to our defconfig, as it's
     always present.

  I've given these a simple build+boot test"

* tag 'riscv-for-linus-4.18-merge_window' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux:
  RISC-V: Add CONFIG_HVC_RISCV_SBI=y to defconfig
  RISC-V: Handle R_RISCV_32 in modules
  riscv/ftrace: Export _mcount when DYNAMIC_FTRACE isn't set
  riscv: add riscv-specific predefines to CHECKFLAGS
  riscv: split the declaration of __copy_user
  riscv: no __user for probe_kernel_address()
  riscv: use NULL instead of a plain 0
  perf: riscv: Add Document for Future Porting Guide
  perf: riscv: preliminary RISC-V support
  MAINTAINERS: Update Albert's email, he's back at Berkeley
  MAINTAINERS: Add myself as a maintainer for SiFive's drivers
  riscv: Fix the bug in memory access fixup code

Pull more kvm updates from Paolo Bonzini:
 "Mostly the PPC part of the release, but also switching to Arnd's fix
  for the hyperv config issue and a typo fix.

  Main PPC changes:

   - reimplement the MMIO instruction emulation

   - transactional memory support for PR KVM

   - improve radix page table handling"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (63 commits)
  KVM: x86: VMX: redo fix for link error without CONFIG_HYPERV
  KVM: x86: fix typo at kvm_arch_hardware_setup comment
  KVM: PPC: Book3S PR: Fix failure status setting in tabort. emulation
  KVM: PPC: Book3S PR: Enable use on POWER9 bare-metal hosts in HPT mode
  KVM: PPC: Book3S PR: Don't let PAPR guest set MSR hypervisor bit
  KVM: PPC: Book3S PR: Fix failure status setting in treclaim. emulation
  KVM: PPC: Book3S PR: Fix MSR setting when delivering interrupts
  KVM: PPC: Book3S PR: Handle additional interrupt types
  KVM: PPC: Book3S PR: Enable kvmppc_get/set_one_reg_pr() for HTM registers
  KVM: PPC: Book3S: Remove load/put vcpu for KVM_GET_REGS/KVM_SET_REGS
  KVM: PPC: Remove load/put vcpu for KVM_GET/SET_ONE_REG ioctl
  KVM: PPC: Move vcpu_load/vcpu_put down to each ioctl case in kvm_arch_vcpu_ioctl
  KVM: PPC: Book3S PR: Enable HTM for PR KVM for KVM_CHECK_EXTENSION ioctl
  KVM: PPC: Book3S PR: Support TAR handling for PR KVM HTM
  KVM: PPC: Book3S PR: Add guard code to prevent returning to guest with PR=0 and Transactional state
  KVM: PPC: Book3S PR: Add emulation for tabort. in privileged state
  KVM: PPC: Book3S PR: Add emulation for trechkpt.
  KVM: PPC: Book3S PR: Add emulation for treclaim.
  KVM: PPC: Book3S PR: Restore NV regs after emulating mfspr from TM SPRs
  KVM: PPC: Book3S PR: Always fail transactions in guest privileged state
  ...

Pull virtio updates from Michael Tsirkin:
 "virtio, vhost: features, fixes

   - PCI virtual function support for virtio

   - DMA barriers for virtio strong barriers

   - bugfixes"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio: update the comments for transport features
  virtio_pci: support enabling VFs
  vhost: fix info leak due to uninitialized memory
  virtio_ring: switch to dma_XX barriers for rpmsg

As files move around, their previous links break. Fix the
references for them.
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>

The old HOWTO was removed a long time ago. The flat table
version is not metioned elsewhere, so just get rid of the
text.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>

This file doesn't exist anymore:
	Documentation/cpu-freq/user-guide.txt

As the ABI already points to Documentation/cpu-freq, just
remove the broken link and the associated text.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>

As files got renamed, their references broke.

Manually fix a series of broken refs at the DT bindings.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>

Rename:
	pinctrl-binding.txt -> pinctrl-bindings.txt

In order to match the current name of this file.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>