Use the new generic EQ API to move all ODP RDMA data structures and logic
form mlx5 core driver into mlx5_ib driver.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Acked-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Add mlx5_eq_{create/destroy}_generic APIs and EQE access methods, for
mlx5 core consumers generic EQs.

This API will be used in downstream patch to move page fault (RDMA ODP)
EQ logic into mlx5_ib rdma driver, hence it will use a generic EQ.

Current mlx5 EQ allocation scheme:
On load mlx5 allocates 4 (for async) + #cores (for data completions)
MSIX vectors, mlx5 core will assign 3 MSIX vectors for internal async
EQs and will use all of the #cores MSIX vectors for completion EQs,
(One vector is going to be reserved for a generic EQ).

After this patch an external user (e.g mlx5_ib) of mlx5_core
can use this new API to create new generic EQs with the reserved msix
vector index for that eq.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

In mlx5 we have three types of usages for EQs,
1. Asynchronous EQs, used internally by mlx5 core for
 a. FW command completions
 b. FW page requests
 c. one EQ for all other Asynchronous events

2. Completion EQs, used for CQ completion (we create one per core)

3. *Special type of EQ (page fault) used for RDMA on demand paging
(ODP).

*The 3rd type shouldn't be special at least in mlx5 core, it is yet
another async events EQ with specific use case, it will be removed in
the next two patches, and will completely move its logic to mlx5_ib,
as it is rdma specific.

In this patch we remove use case (eq type) specific fields from
struct mlx5_eq into a new eq type specific structures.

struct mlx5_eq_async;
truct mlx5_eq_comp;
struct mlx5_eq_pagefault;

Separate between their type specific flows.

In the future we will allow users to create there own generic EQs.
for now we will allow only one for ODP in next patches.

We will introduce event listeners registration API for those who
want to receive mlx5 async events.
After that mlx5 eq handling will be clean from feature/user specific
handling.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Move unnecessary EQ table structures and declaration from the
public include/linux/mlx5/driver.h into the private area of mlx5_core
and into eq.c/eq.h.

Introduce new mlx5 EQ APIs:

mlx5_comp_vectors_count(dev);
mlx5_comp_irq_get_affinity_mask(dev, vector);

And use them from mlx5_ib or mlx5e netdevice instead of direct access to
mlx5_core internal structures.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

irq_info and rmap are EQ properties of the driver, and only needed for
EQ objects, move them to the eq_table EQs database structure.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Instead of creating the EQ table in three steps at driver load,
 - allocate irq vectors
 - allocate async EQs
 - allocate completion EQs
Gather all of the procedures into one function in eq.c and call it from
driver load.

This will help us reduce the EQ and EQ table private structures
visibility to eq.c in downstream refactoring.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Move completion EQs flows from main.c to eq.c, reasons:
1) It is where this logic belongs.
2) It will help centralize the EQ logic in one file for downstream
refactoring, and future extensions/updates.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Completion EQs list is only modified on driver load/unload, locking is
not required, remove it.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

eq->index is used only for completion EQs and is assigned to be
the completion eq index, it is used only when traversing the completion
eqs list, and it can be calculated dynamically, thus remove the
eq->index field.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Some fields and structures are not referenced nor used by the driver,
remove them.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Currently the cpu affinity hint mask for completion EQs is stored and
read from the wrong place, since reading and storing is done from the
same index, there is no actual issue with that, but internal irq_info
for completion EQs stars at MLX5_EQ_VEC_COMP_BASE offset in irq_info
array, this patch changes the code to use the correct offset to store
and read the IRQ affinity hint.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Add and modify debug messages to ODP related error flows.
In that context, return code EAGAIN is considered less severe and print
level for it is set debug instead of warn.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Page fault events are processed in a workqueue context. Since each QP
can have up to two concurrent unrelated page-faults, one for requester
and one for responder, page-fault handling can be done in parallel.
Achieve this by changing the workqueue to be multi-threaded.
The number of threads is the same as the number of command interface
channels to avoid command interface bottlenecks.

In addition to multi-threads, change the workqueue flags to give it high
priority.

Stress benchmark shows that before this change 85% of page faults were
waiting in queue 8 seconds or more while after the change 98% of page
faults were waiting in queue 64 milliseconds or less. The number of threads
was chosen as the number of channels to the command interface.

Fixes: d9aaed83 ("{net,IB}/mlx5: Refactor page fault handling")
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

When the device is in internal error state, command interface isn't
accessible and the driver decides which commands to fail and which to
pass.
Move the PAGE_FAULT_RESUME command to the pass list in order to avoid
redundant failure messages.

Fixes: 89d44f0a ("net/mlx5_core: Add pci error handlers to mlx5_core driver")
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

When page fault event for a WQE arrives, the event data contains the
resource (e.g. QP) number which will later be used by the page fault
handler to retrieve the resource. Meanwhile, another context can destroy
the resource and cause use-after-free. To avoid that, take a reference on the
resource when handler starts and release it when it ends.

Page fault events for RDMA operations don't need to be protected because
the driver doesn't need to access the QP in the page fault handler.

Fixes: d9aaed83 ("{net,IB}/mlx5: Refactor page fault handling")
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Give meaningful names to type of WQE page faults.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Sometimes upper layers may want to prevent the destruction of a core
resource for a period of time while work on that resource is in
progress.  Add API to support this.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Fix reference counting leakage when the event handler aborts due to an
unsupported event for the resource type.

Fixes: a14c2d4b ("net/mlx5_core: Warn on unsupported events of QP/RQ/SQ")
Signed-off-by: Moni Shoua <monis@mellanox.com>
Reviewed-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Fix wrong offsets of reserved fields in ifc file.
Issues found using pahole.
Signed-off-by: Gal Pressman <pressmangal@gmail.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Adapt XRC SRQ to the latest HW specification with fixed definition
around umem valid bits. The previous definition relied on a bit which
was taken for other purposes in legacy FW.

Fixes: bd371975 ("net/mlx5: Update mlx5_ifc with DEVX UID bits")
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Pull UBIFS updates from Richard Weinberger:

 - Full filesystem authentication feature, UBIFS is now able to have the
   whole filesystem structure authenticated plus user data encrypted and
   authenticated.

 - Minor cleanups

* tag 'tags/upstream-4.20-rc1' of git://git.infradead.org/linux-ubifs: (26 commits)
  ubifs: Remove unneeded semicolon
  Documentation: ubifs: Add authentication whitepaper
  ubifs: Enable authentication support
  ubifs: Do not update inode size in-place in authenticated mode
  ubifs: Add hashes and HMACs to default filesystem
  ubifs: authentication: Authenticate super block node
  ubifs: Create hash for default LPT
  ubfis: authentication: Authenticate master node
  ubifs: authentication: Authenticate LPT
  ubifs: Authenticate replayed journal
  ubifs: Add auth nodes to garbage collector journal head
  ubifs: Add authentication nodes to journal
  ubifs: authentication: Add hashes to index nodes
  ubifs: Add hashes to the tree node cache
  ubifs: Create functions to embed a HMAC in a node
  ubifs: Add helper functions for authentication support
  ubifs: Add separate functions to init/crc a node
  ubifs: Format changes for authentication support
  ubifs: Store read superblock node
  ubifs: Drop write_node
  ...

Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

  Bugfix:
   - Fix build issues on architectures that don't provide 64-bit cmpxchg

  Cleanups:
   - Fix a spelling mistake"

* tag 'nfs-for-4.20-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFS: fix spelling mistake, EACCESS -> EACCES
  SUNRPC: Use atomic(64)_t for seq_send(64)

Pull more timer updates from Thomas Gleixner:
 "A set of commits for the new C-SKY architecture timers"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  dt-bindings: timer: gx6605s SOC timer
  clocksource/drivers/c-sky: Add gx6605s SOC system timer
  dt-bindings: timer: C-SKY Multi-processor timer
  clocksource/drivers/c-sky: Add C-SKY SMP timer

Pull NTB updates from Jon Mason:
 "Fairly minor changes and bug fixes:

  NTB IDT thermal changes and hook into hwmon, ntb_netdev clean-up of
  private struct, and a few bug fixes"

* tag 'ntb-4.20' of git://github.com/jonmason/ntb:
  ntb: idt: Alter the driver info comments
  ntb: idt: Discard temperature sensor IRQ handler
  ntb: idt: Add basic hwmon sysfs interface
  ntb: idt: Alter temperature read method
  ntb_netdev: Simplify remove with client device drvdata
  NTB: transport: Try harder to alloc an aligned MW buffer
  ntb: ntb_transport: Mark expected switch fall-throughs
  ntb: idt: Set PCIe bus address to BARLIMITx
  NTB: ntb_hw_idt: replace IS_ERR_OR_NULL with regular NULL checks
  ntb: intel: fix return value for ndev_vec_mask()
  ntb_netdev: fix sleep time mismatch

Pull scheduler fixes from Ingo Molnar:
 "A memory (under-)allocation fix and a comment fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/topology: Fix off by one bug
  sched/rt: Update comment in pick_next_task_rt()

Pull x86 fixes from Ingo Molnar:
 "A number of fixes and some late updates:

   - make in_compat_syscall() behavior on x86-32 similar to other
     platforms, this touches a number of generic files but is not
     intended to impact non-x86 platforms.

   - objtool fixes

   - PAT preemption fix

   - paravirt fixes/cleanups

   - cpufeatures updates for new instructions

   - earlyprintk quirk

   - make microcode version in sysfs world-readable (it is already
     world-readable in procfs)

   - minor cleanups and fixes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  compat: Cleanup in_compat_syscall() callers
  x86/compat: Adjust in_compat_syscall() to generic code under !COMPAT
  objtool: Support GCC 9 cold subfunction naming scheme
  x86/numa_emulation: Fix uniform-split numa emulation
  x86/paravirt: Remove unused _paravirt_ident_32
  x86/mm/pat: Disable preemption around __flush_tlb_all()
  x86/paravirt: Remove GPL from pv_ops export
  x86/traps: Use format string with panic() call
  x86: Clean up 'sizeof x' => 'sizeof(x)'
  x86/cpufeatures: Enumerate MOVDIR64B instruction
  x86/cpufeatures: Enumerate MOVDIRI instruction
  x86/earlyprintk: Add a force option for pciserial device
  objtool: Support per-function rodata sections
  x86/microcode: Make revision and processor flags world-readable

Pull perf updates and fixes from Ingo Molnar:
 "These are almost all tooling updates: 'perf top', 'perf trace' and
  'perf script' fixes and updates, an UAPI header sync with the merge
  window versions, license marker updates, much improved Sparc support
  from David Miller, and a number of fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (66 commits)
  perf intel-pt/bts: Calculate cpumode for synthesized samples
  perf intel-pt: Insert callchain context into synthesized callchains
  perf tools: Don't clone maps from parent when synthesizing forks
  perf top: Start display thread earlier
  tools headers uapi: Update linux/if_link.h header copy
  tools headers uapi: Update linux/netlink.h header copy
  tools headers: Sync the various kvm.h header copies
  tools include uapi: Update linux/mmap.h copy
  perf trace beauty: Use the mmap flags table generated from headers
  perf beauty: Wire up the mmap flags table generator to the Makefile
  perf beauty: Add a generator for MAP_ mmap's flag constants
  tools include uapi: Update asound.h copy
  tools arch uapi: Update asm-generic/unistd.h and arm64 unistd.h copies
  tools include uapi: Update linux/fs.h copy
  perf callchain: Honour the ordering of PERF_CONTEXT_{USER,KERNEL,etc}
  perf cs-etm: Correct CPU mode for samples
  perf unwind: Take pgoff into account when reporting elf to libdwfl
  perf top: Do not use overwrite mode by default
  perf top: Allow disabling the overwrite mode
  perf trace: Beautify mount's first pathname arg
  ...

Pull irq fixes from Ingo Molnar:
 "An irqchip driver fix and a memory (over-)allocation fix"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/irq-mvebu-sei: Fix a NULL vs IS_ERR() bug in probe function
  irq/matrix: Fix memory overallocation

With the addition of the NUMA identity level, we increased @level by
one and will run off the end of the array in the distance sort loop.

Fixed: 051f3ca0 ("sched/topology: Introduce NUMA identity node sched domain")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Pull ARM SoC fixes from Olof Johansson:
 "A few fixes who have come in near or during the merge window:

   - Removal of a VLA usage in Marvell mpp platform code

   - Enable some IPMI options for ARM64 servers by default, helps
     testing

   - Enable PREEMPT on 32-bit ARMv7 defconfig

   - Minor fix for stm32 DT (removal of an unused DMA property)

   - Bugfix for TI OMAP1-based ams-delta (-EINVAL -> IRQ_NOTCONNECTED)"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: dts: stm32: update HASH1 dmas property on stm32mp157c
  ARM: orion: avoid VLA in orion_mpp_conf
  ARM: defconfig: Update multi_v7 to use PREEMPT
  arm64: defconfig: Enable some IPMI configs
  soc: ti: QMSS: Fix usage of irq_set_affinity_hint
  ARM: OMAP1: ams-delta: Fix impossible .irq < 0

Pull more arm64 updates from Catalin Marinas:

 - fix W+X page (mark RO) allocated by the arm64 kprobes code

 - Makefile fix for .i files in out of tree modules

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: kprobe: make page to RO mode when allocate it
  arm64: kdump: fix small typo
  arm64: makefile fix build of .i file in external module case

Pull dma-mapping fix from Christoph Hellwig:
 "Avoid compile warnings on non-default arm64 configs"

* tag 'dma-mapping-4.20-2' of git://git.infradead.org/users/hch/dma-mapping:
  arm64: fix warnings without CONFIG_IOMMU_DMA

Pull Kbuild updates from Masahiro Yamada:

 - clean-up leftovers in Kconfig files

 - remove stale oldnoconfig and silentoldconfig targets

 - remove unneeded cc-fullversion and cc-name variables

 - improve merge_config script to allow overriding option prefix

* tag 'kbuild-v4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: remove cc-name variable
  kbuild: replace cc-name test with CONFIG_CC_IS_CLANG
  merge_config.sh: Allow to define config prefix
  kbuild: remove unused cc-fullversion variable
  kconfig: remove silentoldconfig target
  kconfig: remove oldnoconfig target
  powerpc: PCI_MSI needs PCI
  powerpc: remove CONFIG_MCA leftovers
  powerpc: remove CONFIG_PCI_QSPAN
  scsi: aha152x: rename the PCMCIA define

Pull cifs fixes and updates from Steve French:
 "Three small fixes (one Kerberos related, one for stable, and another
  fixes an oops in xfstest 377), two helpful debugging improvements,
  three patches for cifs directio and some minor cleanup"

* tag '4.20-rc1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix signed/unsigned mismatch on aio_read patch
  cifs: don't dereference smb_file_target before null check
  CIFS: Add direct I/O functions to file_operations
  CIFS: Add support for direct I/O write
  CIFS: Add support for direct I/O read
  smb3: missing defines and structs for reparse point handling
  smb3: allow more detailed protocol info on open files for debugging
  smb3: on kerberos mount if server doesn't specify auth type use krb5
  smb3: add trace point for tree connection
  cifs: fix spelling mistake, EACCESS -> EACCES
  cifs: fix return value for cifs_listxattr

Pull 9p fix from Al Viro:
 "Regression fix for net/9p handling of iov_iter; broken by braino when
  switching to iov_iter_is_kvec() et.al., spotted and fixed by Marc"

* 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  iov_iter: Fix 9p virtio breakage

Pull more SCSI updates from James Bottomley:
 "This is a set of minor small (and safe changes) that didn't make the
  initial pull request plus some bug fixes"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: mvsas: Remove set but not used variable 'id'
  scsi: qla2xxx: Remove two arguments from qlafx00_error_entry()
  scsi: qla2xxx: Make sure that qlafx00_ioctl_iosb_entry() initializes 'res'
  scsi: qla2xxx: Remove a set-but-not-used variable
  scsi: qla2xxx: Make qla2x00_sysfs_write_nvram() easier to analyze
  scsi: qla2xxx: Declare local functions 'static'
  scsi: qla2xxx: Improve several kernel-doc headers
  scsi: qla2xxx: Modify fall-through annotations
  scsi: 3w-sas: 3w-9xxx: Use unsigned char for cdb
  scsi: mvsas: Use dma_pool_zalloc
  scsi: target: Don't request modules that aren't even built
  scsi: target: Set response length for REPORT TARGET PORT GROUPS

Merge more updates from Andrew Morton:

 - more ocfs2 work

 - various leftovers

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  memory_hotplug: cond_resched in __remove_pages
  bfs: add sanity check at bfs_fill_super()
  kernel/sysctl.c: remove duplicated include
  kernel/kexec_file.c: remove some duplicated includes
  mm, thp: consolidate THP gfp handling into alloc_hugepage_direct_gfpmask
  ocfs2: fix clusters leak in ocfs2_defrag_extent()
  ocfs2: dlmglue: clean up timestamp handling
  ocfs2: don't put and assigning null to bh allocated outside
  ocfs2: fix a misuse a of brelse after failing ocfs2_check_dir_entry
  ocfs2: don't use iocb when EIOCBQUEUED returns
  ocfs2: without quota support, avoid calling quota recovery
  ocfs2: remove ocfs2_is_o2cb_active()
  mm: thp: relax __GFP_THISNODE for MADV_HUGEPAGE mappings
  include/linux/notifier.h: SRCU: fix ctags
  mm: handle no memcg case in memcg_kmem_charge() properly

We have received a bug report that unbinding a large pmem (>1TB) can
result in a soft lockup:

  NMI watchdog: BUG: soft lockup - CPU#9 stuck for 23s! [ndctl:4365]
  [...]
  Supported: Yes
  CPU: 9 PID: 4365 Comm: ndctl Not tainted 4.12.14-94.40-default #1 SLE12-SP4
  Hardware name: Intel Corporation S2600WFD/S2600WFD, BIOS SE5C620.86B.01.00.0833.051120182255 05/11/2018
  task: ffff9cce7d4410c0 task.stack: ffffbe9eb1bc4000
  RIP: 0010:__put_page+0x62/0x80
  Call Trace:
   devm_memremap_pages_release+0x152/0x260
   release_nodes+0x18d/0x1d0
   device_release_driver_internal+0x160/0x210
   unbind_store+0xb3/0xe0
   kernfs_fop_write+0x102/0x180
   __vfs_write+0x26/0x150
   vfs_write+0xad/0x1a0
   SyS_write+0x42/0x90
   do_syscall_64+0x74/0x150
   entry_SYSCALL_64_after_hwframe+0x3d/0xa2
  RIP: 0033:0x7fd13166b3d0

It has been reported on an older (4.12) kernel but the current upstream
code doesn't cond_resched in the hot remove code at all and the given
range to remove might be really large.  Fix the issue by calling
cond_resched once per memory section.

Link: http://lkml.kernel.org/r/20181031125840.23982-1-mhocko@kernel.orgSigned-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Dan Williams <dan.j.williams@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>