hmm_mirror_register() registers a callback for when the CPU pagetable is
modified.  Normally, the device driver will call hmm_mirror_unregister()
when the process using the device is finished.  However, if the process
exits uncleanly, the struct_mm can be destroyed with no warning to the
device driver.

Link: http://lkml.kernel.org/r/20180323005527.758-4-jglisse@redhat.comSigned-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Evgeny Baskakov <ebaskakov@nvidia.com>
Cc: Mark Hairgrove <mhairgrove@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The #if/#else/#endif for IS_ENABLED(CONFIG_HMM) were wrong.  Because of
this after multiple include there was multiple definition of both
hmm_mm_init() and hmm_mm_destroy() leading to build failure if HMM was
enabled (CONFIG_HMM set).

Link: http://lkml.kernel.org/r/20180323005527.758-3-jglisse@redhat.comSigned-off-by: Jérôme Glisse <jglisse@redhat.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Evgeny Baskakov <ebaskakov@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Update the documentation for HMM to fix minor typos and phrasing to be a
bit more readable.

Link: http://lkml.kernel.org/r/20180323005527.758-2-jglisse@redhat.comSigned-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Cc: Stephen  Bates <sbates@raithlin.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Evgeny Baskakov <ebaskakov@nvidia.com>
Cc: Mark Hairgrove <mhairgrove@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The trace event trace_mm_vmscan_lru_shrink_inactive() currently has 12
parameters! Seven of them are from the reclaim_stat structure.  This
structure is currently local to mm/vmscan.c.  By moving it to the global
vmstat.h header, we can also reference it from the vmscan tracepoints.
In moving it, it brings down the overhead of passing so many arguments
to the trace event.  In the future, we may limit the number of arguments
that a trace event may pass (ideally just 6, but more realistically it
may be 8).

Before this patch, the code to call the trace event is this:

 0f 83 aa fe ff ff       jae    ffffffff811e6261 <shrink_inactive_list+0x1e1>
 48 8b 45 a0             mov    -0x60(%rbp),%rax
 45 8b 64 24 20          mov    0x20(%r12),%r12d
 44 8b 6d d4             mov    -0x2c(%rbp),%r13d
 8b 4d d0                mov    -0x30(%rbp),%ecx
 44 8b 75 cc             mov    -0x34(%rbp),%r14d
 44 8b 7d c8             mov    -0x38(%rbp),%r15d
 48 89 45 90             mov    %rax,-0x70(%rbp)
 8b 83 b8 fe ff ff       mov    -0x148(%rbx),%eax
 8b 55 c0                mov    -0x40(%rbp),%edx
 8b 7d c4                mov    -0x3c(%rbp),%edi
 8b 75 b8                mov    -0x48(%rbp),%esi
 89 45 80                mov    %eax,-0x80(%rbp)
 65 ff 05 e4 f7 e2 7e    incl   %gs:0x7ee2f7e4(%rip)        # 15bd0 <__preempt_count>
 48 8b 05 75 5b 13 01    mov    0x1135b75(%rip),%rax        # ffffffff8231bf68 <__tracepoint_mm_vmscan_lru_shrink_inactive+0x28>
 48 85 c0                test   %rax,%rax
 74 72                   je     ffffffff811e646a <shrink_inactive_list+0x3ea>
 48 89 c3                mov    %rax,%rbx
 4c 8b 10                mov    (%rax),%r10
 89 f8                   mov    %edi,%eax
 48 89 85 68 ff ff ff    mov    %rax,-0x98(%rbp)
 89 f0                   mov    %esi,%eax
 48 89 85 60 ff ff ff    mov    %rax,-0xa0(%rbp)
 89 c8                   mov    %ecx,%eax
 48 89 85 78 ff ff ff    mov    %rax,-0x88(%rbp)
 89 d0                   mov    %edx,%eax
 48 89 85 70 ff ff ff    mov    %rax,-0x90(%rbp)
 8b 45 8c                mov    -0x74(%rbp),%eax
 48 8b 7b 08             mov    0x8(%rbx),%rdi
 48 83 c3 18             add    $0x18,%rbx
 50                      push   %rax
 41 54                   push   %r12
 41 55                   push   %r13
 ff b5 78 ff ff ff       pushq  -0x88(%rbp)
 41 56                   push   %r14
 41 57                   push   %r15
 ff b5 70 ff ff ff       pushq  -0x90(%rbp)
 4c 8b 8d 68 ff ff ff    mov    -0x98(%rbp),%r9
 4c 8b 85 60 ff ff ff    mov    -0xa0(%rbp),%r8
 48 8b 4d 98             mov    -0x68(%rbp),%rcx
 48 8b 55 90             mov    -0x70(%rbp),%rdx
 8b 75 80                mov    -0x80(%rbp),%esi
 41 ff d2                callq  *%r10

After the patch:

 0f 83 a8 fe ff ff       jae    ffffffff811e626d <shrink_inactive_list+0x1cd>
 8b 9b b8 fe ff ff       mov    -0x148(%rbx),%ebx
 45 8b 64 24 20          mov    0x20(%r12),%r12d
 4c 8b 6d a0             mov    -0x60(%rbp),%r13
 65 ff 05 f5 f7 e2 7e    incl   %gs:0x7ee2f7f5(%rip)        # 15bd0 <__preempt_count>
 4c 8b 35 86 5b 13 01    mov    0x1135b86(%rip),%r14        # ffffffff8231bf68 <__tracepoint_mm_vmscan_lru_shrink_inactive+0x28>
 4d 85 f6                test   %r14,%r14
 74 2a                   je     ffffffff811e6411 <shrink_inactive_list+0x371>
 49 8b 06                mov    (%r14),%rax
 8b 4d 8c                mov    -0x74(%rbp),%ecx
 49 8b 7e 08             mov    0x8(%r14),%rdi
 49 83 c6 18             add    $0x18,%r14
 4c 89 ea                mov    %r13,%rdx
 45 89 e1                mov    %r12d,%r9d
 4c 8d 45 b8             lea    -0x48(%rbp),%r8
 89 de                   mov    %ebx,%esi
 51                      push   %rcx
 48 8b 4d 98             mov    -0x68(%rbp),%rcx
 ff d0                   callq  *%rax

Link: http://lkml.kernel.org/r/2559d7cb-ec60-1200-2362-04fa34fd02bb@fb.com
Link: http://lkml.kernel.org/r/20180322121003.4177af15@gandalf.local.homeSigned-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reported-by: Alexei Starovoitov <ast@fb.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

memcg reclaim may alter pgdat->flags based on the state of LRU lists in
cgroup and its children.  PGDAT_WRITEBACK may force kswapd to sleep
congested_wait(), PGDAT_DIRTY may force kswapd to writeback filesystem
pages.  But the worst here is PGDAT_CONGESTED, since it may force all
direct reclaims to stall in wait_iff_congested().  Note that only kswapd
have powers to clear any of these bits.  This might just never happen if
cgroup limits configured that way.  So all direct reclaims will stall as
long as we have some congested bdi in the system.

Leave all pgdat->flags manipulations to kswapd.  kswapd scans the whole
pgdat, only kswapd can clear pgdat->flags once node is balanced, thus
it's reasonable to leave all decisions about node state to kswapd.

Why only kswapd? Why not allow to global direct reclaim change these
flags? It is because currently only kswapd can clear these flags.  I'm
less worried about the case when PGDAT_CONGESTED falsely not set, and
more worried about the case when it falsely set.  If direct reclaimer
sets PGDAT_CONGESTED, do we have guarantee that after the congestion
problem is sorted out, kswapd will be woken up and clear the flag? It
seems like there is no such guarantee.  E.g.  direct reclaimers may
eventually balance pgdat and kswapd simply won't wake up (see
wakeup_kswapd()).

Moving pgdat->flags manipulation to kswapd, means that cgroup2 recalim
now loses its congestion throttling mechanism.  Add per-cgroup
congestion state and throttle cgroup2 reclaimers if memcg is in
congestion state.

Currently there is no need in per-cgroup PGDAT_WRITEBACK and PGDAT_DIRTY
bits since they alter only kswapd behavior.

The problem could be easily demonstrated by creating heavy congestion in
one cgroup:

    echo "+memory" > /sys/fs/cgroup/cgroup.subtree_control
    mkdir -p /sys/fs/cgroup/congester
    echo 512M > /sys/fs/cgroup/congester/memory.max
    echo $$ > /sys/fs/cgroup/congester/cgroup.procs
    /* generate a lot of diry data on slow HDD */
    while true; do dd if=/dev/zero of=/mnt/sdb/zeroes bs=1M count=1024; done &
    ....
    while true; do dd if=/dev/zero of=/mnt/sdb/zeroes bs=1M count=1024; done &

and some job in another cgroup:

    mkdir /sys/fs/cgroup/victim
    echo 128M > /sys/fs/cgroup/victim/memory.max

    # time cat /dev/sda > /dev/null
    real    10m15.054s
    user    0m0.487s
    sys     1m8.505s

According to the tracepoint in wait_iff_congested(), the 'cat' spent 50%
of the time sleeping there.

With the patch, cat don't waste time anymore:

    # time cat /dev/sda > /dev/null
    real    5m32.911s
    user    0m0.411s
    sys     0m56.664s

[aryabinin@virtuozzo.com: congestion state should be per-node]
  Link: http://lkml.kernel.org/r/20180406135215.10057-1-aryabinin@virtuozzo.com
[ayabinin@virtuozzo.com: make congestion state per-cgroup-per-node instead of just per-cgroup[
  Link: http://lkml.kernel.org/r/20180406180254.8970-2-aryabinin@virtuozzo.com
Link: http://lkml.kernel.org/r/20180323152029.11084-5-aryabinin@virtuozzo.comSigned-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We have separate LRU list for each memory cgroup.  Memory reclaim
iterates over cgroups and calls shrink_inactive_list() every inactive
LRU list.  Based on the state of a single LRU shrink_inactive_list() may
flag the whole node as dirty,congested or under writeback.  This is
obviously wrong and hurtful.  It's especially hurtful when we have
possibly small congested cgroup in system.  Than *all* direct reclaims
waste time by sleeping in wait_iff_congested().  And the more memcgs in
the system we have the longer memory allocation stall is, because
wait_iff_congested() called on each lru-list scan.

Sum reclaim stats across all visited LRUs on node and flag node as
dirty, congested or under writeback based on that sum.  Also call
congestion_wait(), wait_iff_congested() once per pgdat scan, instead of
once per lru-list scan.

This only fixes the problem for global reclaim case.  Per-cgroup reclaim
may alter global pgdat flags too, which is wrong.  But that is separate
issue and will be addressed in the next patch.

This change will not have any effect on a systems with all workload
concentrated in a single cgroup.

[aryabinin@virtuozzo.com: check nr_writeback against all nr_taken, not just file]
  Link: http://lkml.kernel.org/r/20180406180254.8970-1-aryabinin@virtuozzo.com
Link: http://lkml.kernel.org/r/20180323152029.11084-4-aryabinin@virtuozzo.comSigned-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Only kswapd can have non-zero nr_immediate, and current_may_throttle()
is always true for kswapd (PF_LESS_THROTTLE bit is never set) thus it's
enough to check stat.nr_immediate only.

Link: http://lkml.kernel.org/r/20180315164553.17856-4-aryabinin@virtuozzo.comSigned-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Update some comments that became stale since transiton from per-zone to
per-node reclaim.

Link: http://lkml.kernel.org/r/20180315164553.17856-2-aryabinin@virtuozzo.comSigned-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Indirectly reclaimable memory can consume a significant part of total
memory and it's actually reclaimable (it will be released under actual
memory pressure).

So, the overcommit logic should treat it as free.

Otherwise, it's possible to cause random system-wide memory allocation
failures by consuming a significant amount of memory by indirectly
reclaimable memory, e.g.  dentry external names.

If overcommit policy GUESS is used, it might be used for denial of
service attack under some conditions.

The following program illustrates the approach.  It causes the kernel to
allocate an unreclaimable kmalloc-256 chunk for each stat() call, so
that at some point the overcommit logic may start blocking large
allocation system-wide.

  int main()
  {
  	char buf[256];
  	unsigned long i;
  	struct stat statbuf;

  	buf[0] = '/';
  	for (i = 1; i < sizeof(buf); i++)
  		buf[i] = '_';

  	for (i = 0; 1; i++) {
  		sprintf(&buf[248], "%8lu", i);
  		stat(buf, &statbuf);
  	}

  	return 0;
  }

This patch in combination with related indirectly reclaimable memory
patches closes this issue.

Link: http://lkml.kernel.org/r/20180313130041.8078-1-guro@fb.comSigned-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

I received a report about suspicious growth of unreclaimable slabs on
some machines.  I've found that it happens on machines with low memory
pressure, and these unreclaimable slabs are external names attached to
dentries.

External names are allocated using generic kmalloc() function, so they
are accounted as unreclaimable.  But they are held by dentries, which
are reclaimable, and they will be reclaimed under the memory pressure.

In particular, this breaks MemAvailable calculation, as it doesn't take
unreclaimable slabs into account.  This leads to a silly situation, when
a machine is almost idle, has no memory pressure and therefore has a big
dentry cache.  And the resulting MemAvailable is too low to start a new
workload.

To address the issue, the NR_INDIRECTLY_RECLAIMABLE_BYTES counter is
used to track the amount of memory, consumed by external names.  The
counter is increased in the dentry allocation path, if an external name
structure is allocated; and it's decreased in the dentry freeing path.

To reproduce the problem I've used the following Python script:

  import os

  for iter in range (0, 10000000):
      try:
          name = ("/some_long_name_%d" % iter) + "_" * 220
          os.stat(name)
      except Exception:
          pass

Without this patch:
  $ cat /proc/meminfo | grep MemAvailable
  MemAvailable:    7811688 kB
  $ python indirect.py
  $ cat /proc/meminfo | grep MemAvailable
  MemAvailable:    2753052 kB

With the patch:
  $ cat /proc/meminfo | grep MemAvailable
  MemAvailable:    7809516 kB
  $ python indirect.py
  $ cat /proc/meminfo | grep MemAvailable
  MemAvailable:    7749144 kB

[guro@fb.com: fix indirectly reclaimable memory accounting for CONFIG_SLOB]
  Link: http://lkml.kernel.org/r/20180312194140.19517-1-guro@fb.com
[guro@fb.com: fix indirectly reclaimable memory accounting]
  Link: http://lkml.kernel.org/r/20180313125701.7955-1-guro@fb.com
Link: http://lkml.kernel.org/r/20180305133743.12746-5-guro@fb.comSigned-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Adjust /proc/meminfo MemAvailable calculation by adding the amount of
indirectly reclaimable memory (rounded to the PAGE_SIZE).

Link: http://lkml.kernel.org/r/20180305133743.12746-4-guro@fb.comSigned-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Patch series "indirectly reclaimable memory", v2.

This patchset introduces the concept of indirectly reclaimable memory
and applies it to fix the issue of when a big number of dentries with
external names can significantly affect the MemAvailable value.

This patch (of 3):

Introduce a concept of indirectly reclaimable memory and adds the
corresponding memory counter and /proc/vmstat item.

Indirectly reclaimable memory is any sort of memory, used by the kernel
(except of reclaimable slabs), which is actually reclaimable, i.e.  will
be released under memory pressure.

The counter is in bytes, as it's not always possible to count such
objects in pages.  The name contains BYTES by analogy to
NR_KERNEL_STACK_KB.

Link: http://lkml.kernel.org/r/20180305133743.12746-2-guro@fb.comSigned-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull c6x updates from Mark Salter.

* tag 'for-linus' of git://linux-c6x.org/git/projects/linux-c6x-upstreaming:
  c6x: pass endianness info to sparse
  c6x: fix platforms/plldata.c get_coreid build error
  c6x: remove unused KTHREAD_SIZE definition

Pull MIPS updates from James Hogan:
 "These are the main MIPS changes for 4.17. Rough overview:

   (1) generic platform: Add support for Microsemi Ocelot SoCs

   (2) crypto: Add CRC32 and CRC32C HW acceleration module

   (3) Various cleanups and misc improvements

  More detailed summary:

  Miscellaneous:
   - hang more efficiently on halt/powerdown/restart
   - pm-cps: Block system suspend when a JTAG probe is present
   - expand make help text for generic defconfigs
   - refactor handling of legacy defconfigs
   - determine the entry point from the ELF file header to fix microMIPS
     for certain toolchains
   - introduce isa-rev.h for MIPS_ISA_REV and use to simplify other code

  Minor cleanups:
   - DTS: boston/ci20: Unit name cleanups and correction
   - kdump: Make the default for PHYSICAL_START always 64-bit
   - constify gpio_led in Alchemy, AR7, and TXX9
   - silence a couple of W=1 warnings
   - remove duplicate includes

  Platform support:
  Generic platform:
   - add support for Microsemi Ocelot
   - dt-bindings: Add vendor prefix for Microsemi Corporation
   - dt-bindings: Add bindings for Microsemi SoCs
   - add ocelot SoC & PCB123 board DTS files
   - MAINTAINERS: Add entry for Microsemi MIPS SoCs
   - enable crc32-mips on r6 configs

  ath79:
   - fix AR724X_PLL_REG_PCIE_CONFIG offset

  BCM47xx:
   - firmware: Use mac_pton() for MAC address parsing
   - add Luxul XAP1500/XWR1750 WiFi LEDs
   - use standard reset button for Luxul XWR-1750

  BMIPS:
   - enable CONFIG_BRCMSTB_PM in bmips_stb_defconfig for build coverage
   - add STB PM, wake-up timer, watchdog DT nodes

  Octeon:
   - drop '.' after newlines in printk calls

  ralink:
   - pci-mt7621: Enable PCIe on MT7688"

* tag 'mips_4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips: (37 commits)
  MIPS: BCM47XX: Use standard reset button for Luxul XWR-1750
  MIPS: BCM47XX: Add Luxul XAP1500/XWR1750 WiFi LEDs
  MIPS: Make the default for PHYSICAL_START always 64-bit
  MIPS: Use the entry point from the ELF file header
  MAINTAINERS: Add entry for Microsemi MIPS SoCs
  MIPS: generic: Add support for Microsemi Ocelot
  MIPS: mscc: Add ocelot PCB123 device tree
  MIPS: mscc: Add ocelot dtsi
  dt-bindings: mips: Add bindings for Microsemi SoCs
  dt-bindings: Add vendor prefix for Microsemi Corporation
  MIPS: ath79: Fix AR724X_PLL_REG_PCIE_CONFIG offset
  MIPS: pci-mt7620: Enable PCIe on MT7688
  MIPS: pm-cps: Block system suspend when a JTAG probe is present
  MIPS: VDSO: Replace __mips_isa_rev with MIPS_ISA_REV
  MIPS: BPF: Replace __mips_isa_rev with MIPS_ISA_REV
  MIPS: cpu-features.h: Replace __mips_isa_rev with MIPS_ISA_REV
  MIPS: Introduce isa-rev.h to define MIPS_ISA_REV
  MIPS: Hang more efficiently on halt/powerdown/restart
  FIRMWARE: bcm47xx_nvram: Replace mac address parsing
  MIPS: BMIPS: Add Broadcom STB watchdog nodes
  ...

Pull tracing updates from Steven Rostedt:
 "New features:

   - Tom Zanussi's extended histogram work.

     This adds the synthetic events to have histograms from multiple
     event data Adds triggers "onmatch" and "onmax" to call the
     synthetic events Several updates to the histogram code from this

   - Allow way to nest ring buffer calls in the same context

   - Allow absolute time stamps in ring buffer

   - Rewrite of filter code parsing based on Al Viro's suggestions

   - Setting of trace_clock to global if TSC is unstable (on boot)

   - Better OOM handling when allocating large ring buffers

   - Added initcall tracepoints (consolidated initcall_debug code with
     them)

  And other various fixes and clean ups"

* tag 'trace-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (68 commits)
  init: Have initcall_debug still work without CONFIG_TRACEPOINTS
  init, tracing: Have printk come through the trace events for initcall_debug
  init, tracing: instrument security and console initcall trace events
  init, tracing: Add initcall trace events
  tracing: Add rcu dereference annotation for test func that touches filter->prog
  tracing: Add rcu dereference annotation for filter->prog
  tracing: Fixup logic inversion on setting trace_global_clock defaults
  tracing: Hide global trace clock from lockdep
  ring-buffer: Add set/clear_current_oom_origin() during allocations
  ring-buffer: Check if memory is available before allocation
  lockdep: Add print_irqtrace_events() to __warn
  vsprintf: Do not preprocess non-dereferenced pointers for bprintf (%px and %pK)
  tracing: Uninitialized variable in create_tracing_map_fields()
  tracing: Make sure variable string fields are NULL-terminated
  tracing: Add action comparisons when testing matching hist triggers
  tracing: Don't add flag strings when displaying variable references
  tracing: Fix display of hist trigger expressions containing timestamps
  ftrace: Drop a VLA in module_exists()
  tracing: Mention trace_clock=global when warning about unstable clocks
  tracing: Default to using trace_global_clock if sched_clock is unstable
  ...

Pull libnvdimm updates from Dan Williams:
 "This cycle was was not something I ever want to repeat as there were
  several late changes that have only now just settled.

  Half of the branch up to commit d2c997c0 ("fs, dax: use
  page->mapping to warn...") have been in -next for several releases.
  The of_pmem driver and the address range scrub rework were late
  arrivals, and the dax work was scaled back at the last moment.

  The of_pmem driver missed a previous merge window due to an oversight.
  A sense of obligation to rectify that miss is why it is included for
  4.17. It has acks from PowerPC folks. Stephen reported a build failure
  that only occurs when merging it with your latest tree, for now I have
  fixed that up by disabling modular builds of of_pmem. A test merge
  with your tree has received a build success report from the 0day robot
  over 156 configs.

  An initial version of the ARS rework was submitted before the merge
  window. It is self contained to libnvdimm, a net code reduction, and
  passing all unit tests.

  The filesystem-dax changes are based on the wait_var_event()
  functionality from tip/sched/core. However, late review feedback
  showed that those changes regressed truncate performance to a large
  degree. The branch was rewound to drop the truncate behavior change
  and now only includes preparation patches and cleanups (with full acks
  and reviews). The finalization of this dax-dma-vs-trnucate work will
  need to wait for 4.18.

  Summary:

   - A rework of the filesytem-dax implementation provides for detection
     of unmap operations (truncate / hole punch) colliding with
     in-progress device-DMA. A fix for these collisions remains a
     work-in-progress pending resolution of truncate latency and
     starvation regressions.

   - The of_pmem driver expands the users of libnvdimm outside of x86
     and ACPI to describe an implementation of persistent memory on
     PowerPC with Open Firmware / Device tree.

   - Address Range Scrub (ARS) handling is completely rewritten to
     account for the fact that ARS may run for 100s of seconds and there
     is no platform defined way to cancel it. ARS will now no longer
     block namespace initialization.

   - The NVDIMM Namespace Label implementation is updated to handle
     label areas as small as 1K, down from 128K.

   - Miscellaneous cleanups and updates to unit test infrastructure"

* tag 'libnvdimm-for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (39 commits)
  libnvdimm, of_pmem: workaround OF_NUMA=n build error
  nfit, address-range-scrub: add module option to skip initial ars
  nfit, address-range-scrub: rework and simplify ARS state machine
  nfit, address-range-scrub: determine one platform max_ars value
  powerpc/powernv: Create platform devs for nvdimm buses
  doc/devicetree: Persistent memory region bindings
  libnvdimm: Add device-tree based driver
  libnvdimm: Add of_node to region and bus descriptors
  libnvdimm, region: quiet region probe
  libnvdimm, namespace: use a safe lookup for dimm device name
  libnvdimm, dimm: fix dpa reservation vs uninitialized label area
  libnvdimm, testing: update the default smart ctrl_temperature
  libnvdimm, testing: Add emulation for smart injection commands
  nfit, address-range-scrub: introduce nfit_spa->ars_state
  libnvdimm: add an api to cast a 'struct nd_region' to its 'struct device'
  nfit, address-range-scrub: fix scrub in-progress reporting
  dax, dm: allow device-mapper to operate without dax support
  dax: introduce CONFIG_DAX_DRIVER
  fs, dax: use page->mapping to warn if truncate collides with a busy page
  ext2, dax: introduce ext2_dax_aops
  ...

Pull RTC updates from Alexandre Belloni:
 "This contains a few series that have been in preparation for a while
  and that will help systems with RTCs that will fail in 2038, 2069 or
  2100.

  Subsystem:
   - Add tracepoints
   - Rework of the RTC/nvmem API to allow drivers to discard struct
     nvmem_config after registration
   - New range API, drivers can now expose the useful range of the RTC
   - New offset API the core is now able to add an offset to the RTC
     time, modifying the supported range.
   - Multiple rtc_time64_to_tm fixes
   - Handle time_t overflow on 32 bit platforms in the core instead of
     letting drivers do crazy things.
   - remove rtc_control API

  New driver:
   - Intersil ISL12026

  Drivers:
   - Drivers exposing the RTC non volatile memory have been converted to
     use nvmem
   - Removed useless time and date validation
   - Removed an indirection pattern that was a cargo cult from ancient
     drivers
   - Removed VLA usage
   - Fixed a possible race condition in probe functions
   - AB8540 support is dropped from ab8500
   - pcf85363 now has alarm support"

* tag 'rtc-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (128 commits)
  rtc: snvs: Fix usage of snvs_rtc_enable
  rtc: mt7622: fix module autoloading for OF platform drivers
  rtc: isl12022: use true and false for boolean values
  rtc: ab8500: Drop AB8540 support
  rtc: remove a warning during scripts/kernel-doc step
  rtc: 88pm860x: remove artificial limitation
  rtc: 88pm80x: remove artificial limitation
  rtc: st-lpc: remove artificial limitation
  rtc: mrst: remove artificial limitation
  rtc: mv: remove artificial limitation
  rtc: hctosys: Ensure system time doesn't overflow time_t
  parisc: time: stop validating rtc_time in .read_time
  rtc: pcf85063: fix clearing bits in pcf85063_start_clock
  rtc: at91sam9: Set name of regmap_config
  rtc: s5m: Remove VLA usage
  rtc: s5m: Move enum from rtc.h to rtc-s5m.c
  rtc: remove VLA usage
  rtc: Add useful timestamp definitions
  rtc: Add one offset seconds to expand RTC range
  rtc: Factor out the RTC range validation into rtc_valid_range()
  ...

Pull fbdev updates from Bartlomiej Zolnierkiewicz:
 "There is nothing really major here, just a couple of small bugfixes,
  improvements and cleanups:

   - make it possible to load radeonfb driver when offb driver is loaded
     first (Mathieu Malaterre)

   - fix memory leak in offb driver (Mathieu Malaterre)

   - fix unaligned access in udlfb driver (Ladislav Michl)

   - convert atmel_lcdfb driver to use GPIO descriptors (Ludovic
     Desroches)

   - avoid mismatched prototypes in sisfb driver (Arnd Bergmann)

   - remove VLA usage from viafb driver (Gustavo A. R. Silva)

   - add missing help text to FB_I810_I2 config option (Ulf Magnusson)

   - misc fixes (Gustavo A. R. Silva, Colin Ian King, Markus Elfring)

   - remove dead code from s3c-fb driver for Exynos and S5PV210
     platforms

   - misc cleanups (Corentin Labbe, Ladislav Michl, Ulf Magnusson,
     Vladimir Zapolskiy, Markus Elfring)"

* tag 'fbdev-v4.17' of git://github.com/bzolnier/linux: (32 commits)
  video: fbdev: s3c-fb: remove dead platform code for Exynos and S5PV210 platforms
  video: au1100fb: Delete an unnecessary variable initialisation in au1100fb_drv_probe()
  video: au1100fb: Improve a size determination in au1100fb_drv_probe()
  video: au1100fb: Delete an error message for a failed memory allocation in au1100fb_drv_probe()
  video/console/sticore: Delete an error message for a failed memory allocation in sti_try_rom_generic()
  video: ARM CLCD: Improve a size determination in clcdfb_probe()
  video: ARM CLCD: Delete an error message for a failed memory allocation in clcdfb_probe()
  video: matroxfb: Delete an error message for a failed memory allocation in matroxfb_crtc2_probe()
  video: s3c-fb: Improve a size determination in s3c_fb_probe()
  video: s3c-fb: Delete an error message for a failed memory allocation in s3c_fb_probe()
  video: fsl-diu-fb: Delete an error message for a failed memory allocation in fsl_diu_init()
  video: ssd1307fb: Improve a size determination in ssd1307fb_probe()
  video: smscufx: Delete an error message for a failed memory allocation in ufx_realloc_framebuffer()
  video: smscufx: Return an error code only as a constant in ufx_realloc_framebuffer()
  video: smscufx: Less checks in ufx_usb_probe() after error detection
  video: udlfb: Return an error code only as a constant in dlfb_realloc_framebuffer()
  video/fbdev/stifb: Delete an error message for a failed memory allocation in stifb_init_fb()
  video/fbdev/stifb: Return -ENOMEM after a failed kzalloc() in stifb_init_fb()
  video: fbdev: aty128fb: use true and false for boolean values
  fbdev: aty: fix missing indentation in if statement
  ...

Pull sound fixes from Takashi Iwai:
 "The main purpose of this pull request is a fix for a regression in the
  recent PCM OSS emulation code that may lead to RCU stall. Since
  syzkaller hits this too often, I send the pull request now with a
  minimal collection. Possibly another pull request may follow before
  RC1.

  The other fixes here are for USB-audio class 2 and 3 to improve the
  parser for the clock descriptors. These are rather cleanups but good
  for security, too.

  Last but not least, another included fix is the trivial one to remove
  superfluous WARN_ON() that annoyed syzbot"

* tag 'sound-fix-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: pcm: Remove WARN_ON() at snd_pcm_hw_params() error
  ALSA: pcm: Fix endless loop for XRUN recovery in OSS emulation
  ALSA: usb-audio: Add sanity checks in UAC3 clock parsers
  ALSA: usb-audio: More strict sanity checks for clock parsers
  ALSA: usb-audio: Refactor clock finder helpers

Pull media fixes from Mauro Carvalho Chehab:
 "A series of media updates/fixes for 4.17.

  There are two important core fix patches in this series:

   - A regression fix on Kernel 4.16 with causes it to not work with
     some input devices that depend on media core

   - A fix at compat32 bits with causes it to OOPS on overlay, and
     affects the Kernels where the CVE-2017-13166 was backported

  The remaining ones are other random fixes at the documentation and on
  drivers.

  The biggest part of this series is a set of 18 patches for the Intel
  atomisp driver. Currently, it produces hundreds of warnings/errors on
  sparse/smatch, causing me to sometimes ignore new warnings on other
  drivers that are not so broken. This driver is on really poor state,
  even for staging standards: it has several layers of abstraction on
  it, and it supports two different hardware. Selecting between them
  require to add a define (there isn't even a Kconfig option for such
  purpose). Just on this smatch cleanup, I could easily get rid of 8
  "do-nothing" files. So, I'm seriously considering its removal from
  upstream, if I don't see any real work on addressing the problems
  there along this year"

* tag 'media/v4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (48 commits)
  media: v4l2-core: fix size of devnode_nums[] bitarray
  media: v4l2-compat-ioctl32: don't oops on overlay
  media: i2c: adv748x: afe: fix sparse warning
  media: extended-controls.rst: transmitter -> receiver
  media: staging: atomisp: stop duplicating input format types
  media: staging: atomisp: get rid of an unused var
  media: staging: atomisp: stop mixing enum types
  media: staging: atomisp: get rid of some static warnings
  media: staging: atomisp: use %p to print pointers
  media: staging: atomisp: remove an useless check
  media: staging: atomisp: avoid a warning if 32 bits build
  media: staging: atomisp: don't access a NULL var
  media: staging: atomisp: Get rid of *default.host.[ch]
  media: staging: atomisp: get rid of an unused function
  media: staging: atomisp: remove unused set_pd_base()
  media: staging: atomisp: fix endianess issues
  media: staging: atomisp: add a missing include
  media: staging: atomisp: get rid of stupid statements
  media: staging: atomisp: declare static vars as such
  media: staging: atomisp: ia_css_output.host: don't use var before check
  ...

c6x depends on the macro '_BIG_ENDIAN' being defined or not
to correctly select or define endian-specific macros, structures
or pieces of code.

This macro is predefined by the compiler but sparse knows nothing
about it and thus may pre-process files differently from what
gcc would.

Fix this by passing '-D_BIG_ENDIAN' when compiling a big-endian
kernel, like GCC would have done.

To: Mark Salter <msalter@redhat.com>
To: Aurelien Jacquiot <a-jacquiot@ti.com>
CC: linux-c6x-dev@linux-c6x.org
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Mark Salter <msalter@redhat.com>

Fix build error reported by the 0day bot by including the header
file for that macro.

Fixes this build error: (should fix; not tested)
arch/c6x/platforms/plldata.c: In function 'c6472_setup_clocks':
arch/c6x/platforms/plldata.c:279:33: error: implicit declaration of function 'get_coreid'; did you mean 'get_order'? [-Werror=implicit-function-declaration]
      c6x_core_clk.parent = &sysclks[get_coreid() + 1];
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <jacquiot.aurelien@gmail.com>
Cc: linux-c6x-dev@linux-c6x.org
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Mark Salter <msalter@redhat.com>

KTHREAD_SIZE has never been used since it has been defined for c6x arch.
Let's remove this useless definition.
Signed-off-by: Jérémy Lefaure <jeremy.lefaure@lse.epita.fr>
Signed-off-by: Mark Salter <msalter@redhat.com>

Merge tag 'hwmon-for-linus-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon updates from Guenter Roeck:

 - added chip support: new Centaur CPUs, ADM1272, NCT6796D

 - ucd9000: added debugfs attributes, gpio support

 - cleanup and minor bug fixes

* tag 'hwmon-for-linus-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (via-cputemp) support new centaur CPUs
  hwmon: (nct6775) Fix writing pwmX_mode
  hwmon: (lm92) Add max6635 to lm92_id[]
  hwmon: (pmbus/adm1275) Add support for ADM1272
  hwmon: (lm92) Do not try to detect MAX6635
  hwmon: (ucd9000) Add debugfs attributes to provide mfr_status
  hwmon: (ucd9000) Add gpio chip interface
  hwmon: (nct6775) Add support for NCT6796D
  hwmon: (nct6775) Initialize boolean variables with declaration
  hwmon: (nct6775) Improve fan6/pwm6 support
  hwmon: (nct6775) Use NUM_FAN consistently
  hwmon: (g762) handle cleanup with devm_add_action
  hwmon: (sht3x) Update data sheet URL
  hwmon: (sht21) Update data sheet URLs
  hwmon: (pmbus/adm1275) Accept negative page register values
  hwmon: (pmbus/max8688) Accept negative page register values

Pull networking fixes from David Miller:

 1) The sockmap code has to free socket memory on close if there is
    corked data, from John Fastabend.

 2) Tunnel names coming from userspace need to be length validated. From
    Eric Dumazet.

 3) arp_filter() has to take VRFs properly into account, from Miguel
    Fadon Perlines.

 4) Fix oops in error path of tcf_bpf_init(), from Davide Caratti.

 5) Missing idr_remove() in u32_delete_key(), from Cong Wang.

 6) More syzbot stuff. Several use of uninitialized value fixes all
    over, from Eric Dumazet.

 7) Do not leak kernel memory to userspace in sctp, also from Eric
    Dumazet.

 8) Discard frames from unused ports in DSA, from Andrew Lunn.

 9) Fix DMA mapping and reset/failover problems in ibmvnic, from Thomas
    Falcon.

10) Do not access dp83640 PHY registers prematurely after reset, from
    Esben Haabendal.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (46 commits)
  vhost-net: set packet weight of tx polling to 2 * vq size
  net: thunderx: rework mac addresses list to u64 array
  inetpeer: fix uninit-value in inet_getpeer
  dp83640: Ensure against premature access to PHY registers after reset
  devlink: convert occ_get op to separate registration
  ARM: dts: ls1021a: Specify TBIPA register address
  net/fsl_pq_mdio: Allow explicit speficition of TBIPA address
  ibmvnic: Do not reset CRQ for Mobility driver resets
  ibmvnic: Fix failover case for non-redundant configuration
  ibmvnic: Fix reset scheduler error handling
  ibmvnic: Zero used TX descriptor counter on reset
  ibmvnic: Fix DMA mapping mistakes
  tipc: use the right skb in tipc_sk_fill_sock_diag()
  sctp: sctp_sockaddr_af must check minimal addr length for AF_INET6
  net: dsa: Discard frames from unused ports
  sctp: do not leak kernel memory to user space
  soreuseport: initialise timewait reuseport field
  ipv4: fix uninit-value in ip_route_output_key_hash_rcu()
  dccp: initialize ireq->ir_mark
  net: fix uninit-value in __hw_addr_add_ex()
  ...

Pull vfs namei updates from Al Viro:

 - make lookup_one_len() safe with parent locked only shared(incoming
   afs series wants that)

 - fix of getname_kernel() regression from 2015 (-stable fodder, that
   one).

* 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  getname_kernel() needs to make sure that ->name != ->iname in long case
  make lookup_one_len() safe to use with directory locked shared
  new helper: __lookup_slow()
  merge common parts of lookup_one_len{,_unlocked} into common helper

Pull orangefs updates from Mike Marshall:
 "Fixes and cleanups:

   - Documentation cleanups

   - removal of unused code

   - make some structs static

   - implement Orangefs vm_operations fault callout

   - eliminate two single-use functions and put their cleaned up code in
     line.

   - replace a vmalloc/memset instance with vzalloc

   - fix a race condition bug in wait code"

* tag 'for-linus-4.17-ofs' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
  Orangefs: documentation updates
  orangefs: document package install and xfstests procedure
  orangefs: remove unused code
  orangefs: make several *_operations structs static
  orangefs: implement vm_ops->fault
  orangefs: open code short single-use functions
  orangefs: replace vmalloc and memset with vzalloc
  orangefs: bug fix for a race condition when getting a slot

Pull pstore fix from Kees Cook:
 "Fix another compression Kconfig combination missed in testing (Tobias
  Regnery)"

* tag 'pstore-v4.17-rc1-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  pstore: fix crypto dependencies without compression

Commit 0619f0f5 ("selinux: wrap selinuxfs state") triggers a BUG
when SELinux is runtime-disabled (i.e. systemd or equivalent disables
SELinux before initial policy load via /sys/fs/selinux/disable based on
/etc/selinux/config SELINUX=disabled).

This does not manifest if SELinux is disabled via kernel command line
argument or if SELinux is enabled (permissive or enforcing).

Before:
  SELinux:  Disabled at runtime.
  BUG: Dentry 000000006d77e5c7{i=17,n=null}  still in use (1) [unmount of selinuxfs selinuxfs]

After:
  SELinux:  Disabled at runtime.

Fixes: 0619f0f5 ("selinux: wrap selinuxfs state")
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull kvm updates from Paolo Bonzini:
 "ARM:
   - VHE optimizations

   - EL2 address space randomization

   - speculative execution mitigations ("variant 3a", aka execution past
     invalid privilege register access)

   - bugfixes and cleanups

  PPC:
   - improvements for the radix page fault handler for HV KVM on POWER9

  s390:
   - more kvm stat counters

   - virtio gpu plumbing

   - documentation

   - facilities improvements

  x86:
   - support for VMware magic I/O port and pseudo-PMCs

   - AMD pause loop exiting

   - support for AMD core performance extensions

   - support for synchronous register access

   - expose nVMX capabilities to userspace

   - support for Hyper-V signaling via eventfd

   - use Enlightened VMCS when running on Hyper-V

   - allow userspace to disable MWAIT/HLT/PAUSE vmexits

   - usual roundup of optimizations and nested virtualization bugfixes

  Generic:
   - API selftest infrastructure (though the only tests are for x86 as
     of now)"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (174 commits)
  kvm: x86: fix a prototype warning
  kvm: selftests: add sync_regs_test
  kvm: selftests: add API testing infrastructure
  kvm: x86: fix a compile warning
  KVM: X86: Add Force Emulation Prefix for "emulate the next instruction"
  KVM: X86: Introduce handle_ud()
  KVM: vmx: unify adjacent #ifdefs
  x86: kvm: hide the unused 'cpu' variable
  KVM: VMX: remove bogus WARN_ON in handle_ept_misconfig
  Revert "KVM: X86: Fix SMRAM accessing even if VM is shutdown"
  kvm: Add emulation for movups/movupd
  KVM: VMX: raise internal error for exception during invalid protected mode state
  KVM: nVMX: Optimization: Dont set KVM_REQ_EVENT when VMExit with nested_run_pending
  KVM: nVMX: Require immediate-exit when event reinjected to L2 and L1 event pending
  KVM: x86: Fix misleading comments on handling pending exceptions
  KVM: x86: Rename interrupt.pending to interrupt.injected
  KVM: VMX: No need to clear pending NMI/interrupt on inject realmode interrupt
  x86/kvm: use Enlightened VMCS when running on Hyper-V
  x86/hyper-v: detect nested features
  x86/hyper-v: define struct hv_enlightened_vmcs and clean field bits
  ...

Commit 3c8ba0d6 ("kernel.h: Retain constant expression output for
max()/min()") rewrote our min/max macros to be very clever, but in the
meantime resurrected a variable name shadow issue that we had had
previously fixed in commit 589a9785 ("min/max: remove sparse
warnings when they're nested").

That commit talks about the sparse warnings that this shadowing causes,
which we ignored as just a minor annoyance.  But it turns out that the
sparse warning is the least of our problems.  We actually have a real
bug due to the shadowing through the interaction with "min_not_zero()",
which ends up doing

   min(__x, __y)

internally, and then the new declaration of "__x" and "__y" as new
variables in __cmp_once() results in a complete mess of an expression,
and "min_not_zero()" doesn't work at all.

For some odd reason, this only ever caused (reported) problems on s390,
even though it is a generic issue and most of the (obviously successful)
testing of the problematic commit had happened on other architectures.

Quoting Sebastian Ott:
 "What happened is that the bio build by the partition detection code
  was attempted to be split by the block layer because the block queue
  had a max_sector setting of 0. blk_queue_max_hw_sectors uses
  min_not_zero."

So re-introduce the use of __UNIQUE_ID() to make sure that the min/max
macros do not have these kinds of clashes.

[ That said, __UNIQUE_ID() itself has several issues that make it less
  than wonderful.

  In particular, the "uniqueness" has a fallback on the line number,
  which means that it's not actually unique in more complex cases if you
  don't build with gcc or clang (which have working unique counters that
  aren't tied to line numbers).

  That historical broken fallback also means that we have that pointless
  "prefix" argument that doesn't actually make much sense _except_ for
  the known-broken case. Oh well. ]

Fixes: 3c8ba0d6 ("kernel.h: Retain constant expression output for max()/min()")
Reported-and-tested-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull ARM SA1100 updates from Russell King:
 "We have support for arbitary MMIO registers providing platform GPIOs,
  which allows us to abstract some of the SA11x0 CF support.

  This set of updates makes that change"

* 'for-linus-sa1100' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: sa1100/simpad: switch simpad CF to use gpiod APIs
  ARM: sa1100/shannon: convert to generic CF sockets
  ARM: sa1100/nanoengine: convert to generic CF sockets
  ARM: sa1100/h3xxx: switch h3xxx PCMCIA to use gpiod APIs
  ARM: sa1100/cerf: convert to generic CF sockets
  ARM: sa1100/assabet: convert to generic CF sockets
  ARM: sa1100: provide infrastructure to support generic CF sockets
  pcmcia: sa1100: provide generic CF support

Pull ARM updates from Russell King:
 "A number of core ARM changes:

   - Refactoring linker script by Nicolas Pitre

   - Enable source fortification

   - Add support for Cortex R8"

* 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: decompressor: fix warning introduced in fortify patch
  ARM: 8751/1: Add support for Cortex-R8 processor
  ARM: 8749/1: Kconfig: Add ARCH_HAS_FORTIFY_SOURCE
  ARM: simplify and fix linker script for TCM
  ARM: linker script: factor out TCM bits
  ARM: linker script: factor out vectors and stubs
  ARM: linker script: factor out unwinding table sections
  ARM: linker script: factor out stuff for the .text section
  ARM: linker script: factor out stuff for the DISCARD section
  ARM: linker script: factor out some common definitions between XIP and non-XIP

Pull m68knommu update from Greg Ungerer:
 "Only a single fix to set the DMA masks in the ColdFire FEC platform
  data structure.

  This stops the warning from dma-mapping.h at boot time"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68k: set dma and coherent masks for platform FEC ethernets

Pull alpha updates from Matt Turner:
 "A few small changes for alpha"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mattst88/alpha:
  alpha: io: reorder barriers to guarantee writeX() and iowriteX() ordering
  alpha: Implement CPU vulnerabilities sysfs functions.
  alpha: rtc: stop validating rtc_time in .read_time
  alpha: rtc: remove unused set_mmss ops

Stephen reports that an x86 allmodconfig build fails to build the
of_pmem driver due to a missing definition of of_node_to_nid(). That
helper is currently only exported in the OF_NUMA=y case. In other cases,
ppc and sparc, it is a weak symbol, and outside of those platforms it is
a static inline.

Until an OF_NUMA=n configuration can reliably support usage of
of_node_to_nid() in modules across architectures, mark this driver as
'bool' instead of 'tristate'.

Cc: Rob Herring <robh@kernel.org>
Cc: Oliver O'Halloran <oohall@gmail.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Pull s390 updates from Martin Schwidefsky:

 - Improvements for the spectre defense:
    * The spectre related code is consolidated to a single file
      nospec-branch.c
    * Automatic enable/disable for the spectre v2 defenses (expoline vs.
      nobp)
    * Syslog messages for specve v2 are added
    * Enable CONFIG_GENERIC_CPU_VULNERABILITIES and define the attribute
      functions for spectre v1 and v2

 - Add helper macros for assembler alternatives and use them to shorten
   the code in entry.S.

 - Add support for persistent configuration data via the SCLP Store Data
   interface. The H/W interface requires a page table that uses 4K pages
   only, the code to setup such an address space is added as well.

 - Enable virtio GPU emulation in QEMU. To do this the depends
   statements for a few common Kconfig options are modified.

 - Add support for format-3 channel path descriptors and add a binary
   sysfs interface to export the associated utility strings.

 - Add a sysfs attribute to control the IFCC handling in case of
   constant channel errors.

 - The vfio-ccw changes from Cornelia.

 - Bug fixes and cleanups.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (40 commits)
  s390/kvm: improve stack frame constants in entry.S
  s390/lpp: use assembler alternatives for the LPP instruction
  s390/entry.S: use assembler alternatives
  s390: add assembler macros for CPU alternatives
  s390: add sysfs attributes for spectre
  s390: report spectre mitigation via syslog
  s390: add automatic detection of the spectre defense
  s390: move nobp parameter functions to nospec-branch.c
  s390/cio: add util_string sysfs attribute
  s390/chsc: query utility strings via fmt3 channel path descriptor
  s390/cio: rename struct channel_path_desc
  s390/cio: fix unbind of io_subchannel_driver
  s390/qdio: split up CCQ handling for EQBS / SQBS
  s390/qdio: don't retry EQBS after CCQ 96
  s390/qdio: restrict buffer merging to eligible devices
  s390/qdio: don't merge ERROR output buffers
  s390/qdio: simplify math in get_*_buffer_frontier()
  s390/decompressor: trim uncompressed image head during the build
  s390/crypto: Fix kernel crash on aes_s390 module remove.
  s390/defkeymap: fix global init to zero
  ...

snd_pcm_hw_params() (more exactly snd_pcm_hw_params_choose()) contains
a check of the return error from snd_pcm_hw_param_first() and _last()
with snd_BUG_ON() -- i.e. it may trigger WARN_ON() depending on the
kconfig.

This was a valid check in the past, as these functions shouldn't
return any error if the parameters have been already refined via
snd_pcm_hw_refine() beforehand.  However, the recent rewrite
introduced a kmalloc() in snd_pcm_hw_refine() for removing VLA, and
this brought a possibility to trigger an error.  As a result, syzbot
caught lots of superfluous kernel WARN_ON() and paniced via fault
injection.

As the WARN_ON() is no longer valid with the introduction of
kmalloc(), let's drop snd_BUG_ON() check, in order to make the world
peaceful place again.

Reported-by: syzbot+803e0047ac3a3096bb4f@syzkaller.appspotmail.com
Fixes: 5730f9f7 ("ALSA: pcm: Remove VLA usage")
Signed-off-by: Takashi Iwai <tiwai@suse.de>