Proxying the cpuif accesses at EL2 makes use of vcpu_data_guest_to_host
and co, which check the endianness, which call into vcpu_read_sys_reg...
which isn't mapped at EL2 (it was inlined before, and got moved OoL
with the VHE optimizations).

The result is of course a nice panic. Let's add some specialized
cruft to keep the broken platforms that require this hack alive.

But, this code used vcpu_data_guest_to_host(), which expected us to
write the value to host memory, instead we have trapped the guest's
read or write to an mmio-device, and are about to replay it using the
host's readl()/writel() which also perform swabbing based on the host
endianness. This goes wrong when both host and guest are big-endian,
as readl()/writel() will undo the guest's swabbing, causing the
big-endian value to be written to device-memory.

What needs doing?
A big-endian guest will have pre-swabbed data before storing, undo this.
If its necessary for the host, writel() will re-swab it.

For a read a big-endian guest expects to swab the data after the load.
The hosts's readl() will correct for host endianness, giving us the
device-memory's value in the register. For a big-endian guest, swab it
as if we'd only done the load.

For a little-endian guest, nothing needs doing as readl()/writel() leave
the correct device-memory value in registers.

Tested on Juno with that rarest of things: a big-endian 64K host.
Based on a patch from Marc Zyngier.
Reported-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Fixes: bf8feb39 ("arm64: KVM: vgic-v2: Add GICV access from HYP")
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

One comment still mentioned process_maintenance operations after
commit af061499 ("KVM: arm/arm64: vgic: Get rid of unnecessary
process_maintenance operation")

Update the comment to point to vgic_fold_lr_state instead, which
is where maintenance interrupts are taken care of.
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

A typo in kvm_vcpu_set_be()'s call:
| vcpu_write_sys_reg(vcpu, SCTLR_EL1, sctlr)
causes us to use the 32bit register value as an index into the sys_reg[]
array, and sail off the end of the linear map when we try to bring up
big-endian secondaries.

| Unable to handle kernel paging request at virtual address ffff80098b982c00
| Mem abort info:
|  ESR = 0x96000045
|  Exception class = DABT (current EL), IL = 32 bits
|   SET = 0, FnV = 0
|   EA = 0, S1PTW = 0
| Data abort info:
|   ISV = 0, ISS = 0x00000045
|   CM = 0, WnR = 1
| swapper pgtable: 4k pages, 48-bit VAs, pgdp = 000000002ea0571a
| [ffff80098b982c00] pgd=00000009ffff8803, pud=0000000000000000
| Internal error: Oops: 96000045 [#1] PREEMPT SMP
| Modules linked in:
| CPU: 2 PID: 1561 Comm: kvm-vcpu-0 Not tainted 4.17.0-rc3-00001-ga912e2261ca6-dirty #1323
| Hardware name: ARM Juno development board (r1) (DT)
| pstate: 60000005 (nZCv daif -PAN -UAO)
| pc : vcpu_write_sys_reg+0x50/0x134
| lr : vcpu_write_sys_reg+0x50/0x134

| Process kvm-vcpu-0 (pid: 1561, stack limit = 0x000000006df4728b)
| Call trace:
|  vcpu_write_sys_reg+0x50/0x134
|  kvm_psci_vcpu_on+0x14c/0x150
|  kvm_psci_0_2_call+0x244/0x2a4
|  kvm_hvc_call_handler+0x1cc/0x258
|  handle_hvc+0x20/0x3c
|  handle_exit+0x130/0x1ec
|  kvm_arch_vcpu_ioctl_run+0x340/0x614
|  kvm_vcpu_ioctl+0x4d0/0x840
|  do_vfs_ioctl+0xc8/0x8d0
|  ksys_ioctl+0x78/0xa8
|  sys_ioctl+0xc/0x18
|  el0_svc_naked+0x30/0x34
| Code: 73620291 604d00b0 00201891 1ab10194 (957a33f8)
|---[ end trace 4b4a4f9628596602 ]---

Fix the order of the arguments.

Fixes: 8d404c4c ("KVM: arm64: Rewrite system register accessors to read/write functions")
CC: Christoffer Dall <cdall@cs.columbia.edu>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Now that we make sure we don't inject multiple instances of the
same GICv2 SGI at the same time, we've made another bug more
obvious:

If we exit with an active SGI, we completely lose track of which
vcpu it came from. On the next entry, we restore it with 0 as a
source, and if that wasn't the right one, too bad. While this
doesn't seem to trouble GIC-400, the architectural model gets
offended and doesn't deactivate the interrupt on EOI.

Another connected issue is that we will happilly make pending
an interrupt from another vcpu, overriding the above zero with
something that is just as inconsistent. Don't do that.

The final issue is that we signal a maintenance interrupt when
no pending interrupts are present in the LR. Assuming we've fixed
the two issues above, we end-up in a situation where we keep
exiting as soon as we've reached the active state, and not be
able to inject the following pending.

The fix comes in 3 parts:
- GICv2 SGIs have their source vcpu saved if they are active on
  exit, and restored on entry
- Multi-SGIs cannot go via the Pending+Active state, as this would
  corrupt the source field
- Multi-SGIs are converted to using MI on EOI instead of NPIE

Fixes: 16ca6a60 ("KVM: arm/arm64: vgic: Don't populate multiple LRs with the same vintid")
Reported-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Although we've implemented PSCI 0.1, 0.2 and 1.0, we expose either 0.1
or 1.0 to a guest, defaulting to the latest version of the PSCI
implementation that is compatible with the requested version. This is
no different from doing a firmware upgrade on KVM.

But in order to give a chance to hypothetical badly implemented guests
that would have a fit by discovering something other than PSCI 0.2,
let's provide a new API that allows userspace to pick one particular
version of the API.

This is implemented as a new class of "firmware" registers, where
we expose the PSCI version. This allows the PSCI version to be
save/restored as part of a guest migration, and also set to
any supported version if the guest requires it.

Cc: stable@vger.kernel.org #4.16
Reviewed-by: Christoffer Dall <cdall@kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

When vgic_prune_ap_list() finds an interrupt that needs to be migrated
to a new VCPU, we should notify this VCPU of the pending interrupt,
since it requires immediate action.
Kick this VCPU once we have added the new IRQ to the list, but only
after dropping the locks.
Reported-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

While generating a message about guests probing for SVE/LORegions
is a useful debugging tool, considering it an error is slightly
over the top, as this is the only way the guest can find out
about the presence of the feature.

Let's turn these message into kvm_debug so that they can only
be seen if CONFIG_DYNAMIC_DEBUG, and kept quiet otherwise.
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Update my e-mail address to a working address.
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Before entering the guest, we check whether our VMID is still
part of the current generation. In order to avoid taking a lock,
we start with checking that the generation is still current, and
only if not current do we take the lock, recheck, and update the
generation and VMID.

This leaves open a small race: A vcpu can bump up the global
generation number as well as the VM's, but has not updated
the VMID itself yet.

At that point another vcpu from the same VM comes in, checks
the generation (and finds it not needing anything), and jumps
into the guest. At this point, we end-up with two vcpus belonging
to the same VM running with two different VMIDs. Eventually, the
VMID used by the second vcpu will get reassigned, and things will
really go wrong...

A simple solution would be to drop this initial check, and always take
the lock. This is likely to cause performance issues. A middle ground
is to convert the spinlock to a rwlock, and only take the read lock
on the fast path. If the check fails at that point, drop it and
acquire the write lock, rechecking the condition.

This ensures that the above scenario doesn't occur.

Cc: stable@vger.kernel.org
Reported-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Shannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Pull more btrfs updates from David Sterba:
 "We have queued a few more fixes (error handling, log replay,
  softlockup) and the rest is SPDX updates that touche almost all files
  so the diffstat is long"

* tag 'for-4.17-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: Only check first key for committed tree blocks
  btrfs: add SPDX header to Kconfig
  btrfs: replace GPL boilerplate by SPDX -- sources
  btrfs: replace GPL boilerplate by SPDX -- headers
  Btrfs: fix loss of prealloc extents past i_size after fsync log replay
  Btrfs: clean up resources during umount after trans is aborted
  btrfs: Fix possible softlock on single core machines
  Btrfs: bail out on error during replay_dir_deletes
  Btrfs: fix NULL pointer dereference in log_dir_items

Pull cifs fixes from Steve French:
 "SMB3 fixes, a few for stable, and some important cleanup work from
  Ronnie of the smb3 transport code"

* tag '4.17-rc1SMB3-Fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: change validate_buf to validate_iov
  cifs: remove rfc1002 hardcoded constants from cifs_discard_remaining_data()
  cifs: Change SMB2_open to return an iov for the error parameter
  cifs: add resp_buf_size to the mid_q_entry structure
  smb3.11: replace a 4 with server->vals->header_preamble_size
  cifs: replace a 4 with server->vals->header_preamble_size
  cifs: add pdu_size to the TCP_Server_Info structure
  SMB311: Improve checking of negotiate security contexts
  SMB3: Fix length checking of SMB3.11 negotiate request
  CIFS: add ONCE flag for cifs_dbg type
  cifs: Use ULL suffix for 64-bit constant
  SMB3: Log at least once if tree connect fails during reconnect
  cifs: smb2pdu: Fix potential NULL pointer dereference

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

  The status handling code is actually a running regression from the
  previous merge window which had an incomplete fix (now reverted) and
  most of the remaining bug fixes are for problems older than the
  current merge window"

[ Side note: this merge also takes the base kernel git repository to 6+
  million objects for the first time. Technically we hit it a couple of
  merges ago already if you count all the tag objects, but now it
  reaches 6M+ objects reachable from HEAD.

  I was joking around that that's when I should switch to 5.0, because
  3.0 happened at the 2M mark, and 4.0 happened at 4M objects. But
  probably not, even if numerology is about as good a reason as any.

                                                              - Linus ]

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: devinfo: Add Microsoft iSCSI target to 1024 sector blacklist
  scsi: cxgb4i: silence overflow warning in t4_uld_rx_handler()
  scsi: dpt_i2o: Use after free in I2ORESETCMD ioctl
  scsi: core: Make scsi_result_to_blk_status() recognize CONDITION MET
  scsi: core: Rename __scsi_error_from_host_byte() into scsi_result_to_blk_status()
  Revert "scsi: core: return BLK_STS_OK for DID_OK in __scsi_error_from_host_byte()"
  scsi: aacraid: Insure command thread is not recursively stopped
  scsi: qla2xxx: Correct setting of SAM_STAT_CHECK_CONDITION
  scsi: qla2xxx: correctly shift host byte
  scsi: qla2xxx: Fix race condition between iocb timeout and initialisation
  scsi: qla2xxx: Avoid double completion of abort command
  scsi: qla2xxx: Fix small memory leak in qla2x00_probe_one on probe failure
  scsi: scsi_dh: Don't look for NULL devices handlers by name
  scsi: core: remove redundant assignment to shost->use_blk_mq

Pull more Kbuild updates from Masahiro Yamada:

 - pass HOSTLDFLAGS when compiling single .c host programs

 - build genksyms lexer and parser files instead of using shipped
   versions

 - rename *-asn1.[ch] to *.asn1.[ch] for suffix consistency

 - let the top .gitignore globally ignore artifacts generated by flex,
   bison, and asn1_compiler

 - let the top Makefile globally clean artifacts generated by flex,
   bison, and asn1_compiler

 - use safer .SECONDARY marker instead of .PRECIOUS to prevent
   intermediate files from being removed

 - support -fmacro-prefix-map option to make __FILE__ a relative path

 - fix # escaping to prepare for the future GNU Make release

 - clean up deb-pkg by using debian tools instead of handrolled
   source/changes generation

 - improve rpm-pkg portability by supporting kernel-install as a
   fallback of new-kernel-pkg

 - extend Kconfig listnewconfig target to provide more information

* tag 'kbuild-v4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig: extend output of 'listnewconfig'
  kbuild: rpm-pkg: use kernel-install as a fallback for new-kernel-pkg
  Kbuild: fix # escaping in .cmd files for future Make
  kbuild: deb-pkg: split generating packaging and build
  kbuild: use -fmacro-prefix-map to make __FILE__ a relative path
  kbuild: mark $(targets) as .SECONDARY and remove .PRECIOUS markers
  kbuild: rename *-asn1.[ch] to *.asn1.[ch]
  kbuild: clean up *-asn1.[ch] patterns from top-level Makefile
  .gitignore: move *-asn1.[ch] patterns to the top-level .gitignore
  kbuild: add %.dtb.S and %.dtb to 'targets' automatically
  kbuild: add %.lex.c and %.tab.[ch] to 'targets' automatically
  genksyms: generate lexer and parser during build instead of shipping
  kbuild: clean up *.lex.c and *.tab.[ch] patterns from top-level Makefile
  .gitignore: move *.lex.c *.tab.[ch] patterns to the top-level .gitignore
  kbuild: use HOSTLDFLAGS for single .c executables

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

   - Address a swiotlb regression which was caused by the recent DMA
     rework and made driver fail because dma_direct_supported() returned
     false

   - Fix a signedness bug in the APIC ID validation which caused invalid
     APIC IDs to be detected as valid thereby bloating the CPU possible
     space.

   - Fix inconsisten config dependcy/select magic for the MFD_CS5535
     driver.

   - Fix a corruption of the physical address space bits when encryption
     has reduced the address space and late cpuinfo updates overwrite
     the reduced bit information with the original value.

   - Dominiks syscall rework which consolidates the architecture
     specific syscall functions so all syscalls can be wrapped with the
     same macros. This allows to switch x86/64 to struct pt_regs based
     syscalls. Extend the clearing of user space controlled registers in
     the entry patch to the lower registers"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic: Fix signedness bug in APIC ID validity checks
  x86/cpu: Prevent cpuinfo_x86::x86_phys_bits adjustment corruption
  x86/olpc: Fix inconsistent MFD_CS5535 configuration
  swiotlb: Use dma_direct_supported() for swiotlb_ops
  syscalls/x86: Adapt syscall_wrapper.h to the new syscall stub naming convention
  syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*()
  syscalls/core, syscalls/x86: Clean up compat syscall stub naming convention
  syscalls/core, syscalls/x86: Clean up syscall stub naming convention
  syscalls/x86: Extend register clearing on syscall entry to lower registers
  syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls on x86_64
  syscalls/x86: Use 'struct pt_regs' based syscall calling for IA32_EMULATION and x32
  syscalls/core: Prepare CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y for compat syscalls
  syscalls/x86: Use 'struct pt_regs' based syscall calling convention for 64-bit syscalls
  syscalls/core: Introduce CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y
  x86/syscalls: Don't pointlessly reload the system call number
  x86/mm: Fix documentation of module mapping range with 4-level paging
  x86/cpuid: Switch to 'static const' specifier

Pull x86 pti updates from Thomas Gleixner:
 "Another series of PTI related changes:

   - Remove the manual stack switch for user entries from the idtentry
     code. This debloats entry by 5k+ bytes of text.

   - Use the proper types for the asm/bootparam.h defines to prevent
     user space compile errors.

   - Use PAGE_GLOBAL for !PCID systems to gain back performance

   - Prevent setting of huge PUD/PMD entries when the entries are not
     leaf entries otherwise the entries to which the PUD/PMD points to
     and are populated get lost"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/pgtable: Don't set huge PUD/PMD on non-leaf entries
  x86/pti: Leave kernel text global for !PCID
  x86/pti: Never implicitly clear _PAGE_GLOBAL for kernel image
  x86/pti: Enable global pages for shared areas
  x86/mm: Do not forbid _PAGE_RW before init for __ro_after_init
  x86/mm: Comment _PAGE_GLOBAL mystery
  x86/mm: Remove extra filtering in pageattr code
  x86/mm: Do not auto-massage page protections
  x86/espfix: Document use of _PAGE_GLOBAL
  x86/mm: Introduce "default" kernel PTE mask
  x86/mm: Undo double _PAGE_PSE clearing
  x86/mm: Factor out pageattr _PAGE_GLOBAL setting
  x86/entry/64: Drop idtentry's manual stack switch for user entries
  x86/uapi: Fix asm/bootparam.h userspace compilation errors

Pull scheduler fixes from Thomas Gleixner:
 "A few scheduler fixes:

   - Prevent a bogus warning vs. runqueue clock update flags in
     do_sched_rt_period_timer()

   - Simplify the helper functions which handle requests for skipping
     the runqueue clock updat.

   - Do not unlock the tunables mutex in the error path of the cpu
     frequency scheduler utils. Its not held.

   - Enforce proper alignement for 'struct util_est' in sched_avg to
     prevent a misalignment fault on IA64"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Force proper alignment of 'struct util_est'
  sched/core: Simplify helpers for rq clock update skip requests
  sched/rt: Fix rq->clock_update_flags < RQCF_ACT_SKIP warning
  sched/cpufreq/schedutil: Fix error path mutex unlock

Pull more perf updates from Thomas Gleixner:
 "A rather large set of perf updates:

  Kernel:

   - Fix various initialization issues

   - Prevent creating [ku]probes for not CAP_SYS_ADMIN users

  Tooling:

   - Show only failing syscalls with 'perf trace --failure' (Arnaldo
     Carvalho de Melo)

            e.g: See what 'openat' syscalls are failing:

        # perf trace --failure -e openat
         762.323 ( 0.007 ms): VideoCapture/4566 openat(dfd: CWD, filename: /dev/video2) = -1 ENOENT No such file or directory
         <SNIP N /dev/videoN open attempts... sigh, where is that improvised camera lid?!? >
         790.228 ( 0.008 ms): VideoCapture/4566 openat(dfd: CWD, filename: /dev/video63) = -1 ENOENT No such file or directory
        ^C#

   - Show information about the event (freq, nr_samples, total
     period/nr_events) in the annotate --tui and --stdio2 'perf
     annotate' output, similar to the first line in the 'perf report
     --tui', but just for the samples for a the annotated symbol
     (Arnaldo Carvalho de Melo)

   - Introduce 'perf version --build-options' to show what features were
     linked, aliased as well as a shorter 'perf -vv' (Jin Yao)

   - Add a "dso_size" sort order (Kim Phillips)

   - Remove redundant ')' in the tracepoint output in 'perf trace'
     (Changbin Du)

   - Synchronize x86's cpufeatures.h, no effect on toolss (Arnaldo
     Carvalho de Melo)

   - Show group details on the title line in the annotate browser and
     'perf annotate --stdio2' output, so that the per-event columns can
     have headers (Arnaldo Carvalho de Melo)

   - Fixup vertical line separating metrics from instructions and
     cleaning unused lines at the bottom, both in the annotate TUI
     browser (Arnaldo Carvalho de Melo)

   - Remove duplicated 'samples' in lost samples warning in
     'perf report' (Arnaldo Carvalho de Melo)

   - Synchronize i915_drm.h, silencing the perf build process,
     automagically adding support for the new DRM_I915_QUERY ioctl
     (Arnaldo Carvalho de Melo)

   - Make auxtrace_queues__add_buffer() allocate struct buffer, from a
     patchkit already applied (Adrian Hunter)

   - Fix the --stdio2/TUI annotate output to include group details, be
     it for a recorded '{a,b,f}' explicit event group or when forcing
     group display using 'perf report --group' for a set of events not
     recorded as a group (Arnaldo Carvalho de Melo)

   - Fix display artifacts in the ui browser (base class for the
     annotate and main report/top TUI browser) related to the extra
     title lines work (Arnaldo Carvalho de Melo)

   - perf auxtrace refactorings, leftovers from a previously partially
     processed patchset (Adrian Hunter)

   - Fix the builtin clang build (Sandipan Das, Arnaldo Carvalho de
     Melo)

   - Synchronize i915_drm.h, silencing a perf build warning and in the
     process automagically adding support for a new ioctl command
     (Arnaldo Carvalho de Melo)

   - Fix a strncpy issue in uprobe tracing"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
  perf/core: Need CAP_SYS_ADMIN to create k/uprobe with perf_event_open()
  tracing/uprobe_event: Fix strncpy corner case
  perf/core: Fix perf_uprobe_init()
  perf/core: Fix perf_kprobe_init()
  perf/core: Fix use-after-free in uprobe_perf_close()
  perf tests clang: Fix function name for clang IR test
  perf clang: Add support for recent clang versions
  perf tools: Fix perf builds with clang support
  perf tools: No need to include namespaces.h in util.h
  perf hists browser: Remove leftover from row returned from refresh
  perf hists browser: Show extra_title_lines in the 'D' debug hotkey
  perf auxtrace: Make auxtrace_queues__add_buffer() do CPU filtering
  tools headers uapi: Synchronize i915_drm.h
  perf report: Remove duplicated 'samples' in lost samples warning
  perf ui browser: Fixup cleaning unused lines at the bottom
  perf annotate browser: Fixup vertical line separating metrics from instructions
  perf annotate: Show group details on the title line
  perf auxtrace: Make auxtrace_queues__add_buffer() allocate struct buffer
  perf/x86/intel: Move regs->flags EXACT bit init
  perf trace: Remove redundant ')'
  ...

Pull x86 EFI bootup fixlet from Thomas Gleixner:
 "A single fix for an early boot warning caused by invoking
  this_cpu_has() before SMP initialization"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Fix bogus warning during EFI bootup, use boot_cpu_has() instead of this_cpu_has() in build_cr3_noflush()

Pull irq affinity fixes from Thomas Gleixner:

  - Fix error path handling in the affinity spreading code

  - Make affinity spreading smarter to avoid issues on systems which
    claim to have hotpluggable CPUs while in fact they can't hotplug
    anything.

    So instead of trying to spread the vectors (and thereby the
    associated device queues) to all possibe CPUs, spread them on all
    present CPUs first. If there are left over vectors after that first
    step they are spread among the possible, but not present CPUs which
    keeps the code backwards compatible for virtual decives and NVME
    which allocate a queue per possible CPU, but makes the spreading
    smarter for devices which have less queues than possible or present
    CPUs.

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/affinity: Spread irq vectors among present CPUs as far as possible
  genirq/affinity: Allow irq spreading from a given starting point
  genirq/affinity: Move actual irq vector spreading into a helper function
  genirq/affinity: Rename *node_to_possible_cpumask as *node_to_cpumask
  genirq/affinity: Don't return with empty affinity masks on error

Pull OpenRISC fixlet from Stafford Horne:
 "Just one small thing here, it came in a while back but I didnt have
  anything in my 4.16 queue, still its the only thing for 4.17 so
  sending it alone.

  Small cleanup: remove unused __ARCH_HAVE_MMU define"

* tag 'for-linus' of git://github.com/openrisc/linux:
  openrisc: remove unused __ARCH_HAVE_MMU define

Pull powerpc fixes from Michael Ellerman:

 - Fix crashes when loading modules built with a different
   CONFIG_RELOCATABLE value by adding CONFIG_RELOCATABLE to vermagic.

 - Fix busy loops in the OPAL NVRAM driver if we get certain error
   conditions from firmware.

 - Remove tlbie trace points from KVM code that's called in real mode,
   because it causes crashes.

 - Fix checkstops caused by invalid tlbiel on Power9 Radix.

 - Ensure the set of CPU features we "know" are always enabled is
   actually the minimal set when we build with support for firmware
   supplied CPU features.

Thanks to: Aneesh Kumar K.V, Anshuman Khandual, Nicholas Piggin.

* tag 'powerpc-4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Fix CPU_FTRS_ALWAYS vs DT CPU features
  powerpc/mm/radix: Fix checkstops caused by invalid tlbiel
  KVM: PPC: Book3S HV: trace_tlbie must not be called in realmode
  powerpc/8xx: Fix build with hugetlbfs enabled
  powerpc/powernv: Fix OPAL NVRAM driver OPAL_BUSY loops
  powerpc/powernv: define a standard delay for OPAL_BUSY type retry loops
  powerpc/fscr: Enable interrupts earlier before calling get_user()
  powerpc/64s: Fix section mismatch warnings from setup_rfi_flush()
  powerpc/modules: Fix crashes by adding CONFIG_RELOCATABLE to vermagic

Merge yet more updates from Andrew Morton:

 - various hotfixes

 - kexec_file updates and feature work

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (27 commits)
  kernel/kexec_file.c: move purgatories sha256 to common code
  kernel/kexec_file.c: allow archs to set purgatory load address
  kernel/kexec_file.c: remove mis-use of sh_offset field during purgatory load
  kernel/kexec_file.c: remove unneeded variables in kexec_purgatory_setup_sechdrs
  kernel/kexec_file.c: remove unneeded for-loop in kexec_purgatory_setup_sechdrs
  kernel/kexec_file.c: split up __kexec_load_puragory
  kernel/kexec_file.c: use read-only sections in arch_kexec_apply_relocations*
  kernel/kexec_file.c: search symbols in read-only kexec_purgatory
  kernel/kexec_file.c: make purgatory_info->ehdr const
  kernel/kexec_file.c: remove checks in kexec_purgatory_load
  include/linux/kexec.h: silence compile warnings
  kexec_file, x86: move re-factored code to generic side
  x86: kexec_file: clean up prepare_elf64_headers()
  x86: kexec_file: lift CRASH_MAX_RANGES limit on crash_mem buffer
  x86: kexec_file: remove X86_64 dependency from prepare_elf64_headers()
  x86: kexec_file: purge system-ram walking from prepare_elf64_headers()
  kexec_file,x86,powerpc: factor out kexec_file_ops functions
  kexec_file: make use of purgatory optional
  proc: revalidate misc dentries
  mm, slab: reschedule cache_reap() on the same CPU
  ...

The code to verify the new kernels sha digest is applicable for all
architectures.  Move it to common code.

One problem is the string.c implementation on x86.  Currently sha256
includes x86/boot/string.h which defines memcpy and memset to be gcc
builtins.  By moving the sha256 implementation to common code and
changing the include to linux/string.h both functions are no longer
defined.  Thus definitions have to be provided in x86/purgatory/string.c

Link: http://lkml.kernel.org/r/20180321112751.22196-12-prudo@linux.vnet.ibm.comSigned-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

For s390 new kernels are loaded to fixed addresses in memory before they
are booted.  With the current code this is a problem as it assumes the
kernel will be loaded to an 'arbitrary' address.  In particular,
kexec_locate_mem_hole searches for a large enough memory region and sets
the load address (kexec_bufer->mem) to it.

Luckily there is a simple workaround for this problem.  By returning 1
in arch_kexec_walk_mem, kexec_locate_mem_hole is turned off.  This
allows the architecture to set kbuf->mem by hand.  While the trick works
fine for the kernel it does not for the purgatory as here the
architectures don't have access to its kexec_buffer.

Give architectures access to the purgatories kexec_buffer by changing
kexec_load_purgatory to take a pointer to it.  With this change
architectures have access to the buffer and can edit it as they need.

A nice side effect of this change is that we can get rid of the
purgatory_info->purgatory_load_address field.  As now the information
stored there can directly be accessed from kbuf->mem.

Link: http://lkml.kernel.org/r/20180321112751.22196-11-prudo@linux.vnet.ibm.comSigned-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The current code uses the sh_offset field in purgatory_info->sechdrs to
store a pointer to the current load address of the section.  Depending
whether the section will be loaded or not this is either a pointer into
purgatory_info->purgatory_buf or kexec_purgatory.  This is not only a
violation of the ELF standard but also makes the code very hard to
understand as you cannot tell if the memory you are using is read-only
or not.

Remove this misuse and store the offset of the section in
pugaroty_info->purgatory_buf in sh_offset.

Link: http://lkml.kernel.org/r/20180321112751.22196-10-prudo@linux.vnet.ibm.comSigned-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The main loop currently uses quite a lot of variables to update the
section headers.  Some of them are unnecessary.  So clean them up a
little.

Link: http://lkml.kernel.org/r/20180321112751.22196-9-prudo@linux.vnet.ibm.comSigned-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

To update the entry point there is an extra loop over all section
headers although this can be done in the main loop.  So move it there
and eliminate the extra loop and variable to store the 'entry section
index'.

Also, in the main loop, move the usual case, i.e.  non-bss section, out
of the extra if-block.

Link: http://lkml.kernel.org/r/20180321112751.22196-8-prudo@linux.vnet.ibm.comSigned-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When inspecting __kexec_load_purgatory you find that it has two tasks

	1) setting up the kexec_buffer for the new kernel and,
	2) setting up pi->sechdrs for the final load address.

The two tasks are independent of each other.  To improve readability
split up __kexec_load_purgatory into two functions, one for each task,
and call them directly from kexec_load_purgatory.

Link: http://lkml.kernel.org/r/20180321112751.22196-7-prudo@linux.vnet.ibm.comSigned-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When the relocations are applied to the purgatory only the section the
relocations are applied to is writable.  The other sections, i.e.  the
symtab and .rel/.rela, are in read-only kexec_purgatory.  Highlight this
by marking the corresponding variables as 'const'.

While at it also change the signatures of arch_kexec_apply_relocations* to
take section pointers instead of just the index of the relocation section.
This removes the second lookup and sanity check of the sections in arch
code.

Link: http://lkml.kernel.org/r/20180321112751.22196-6-prudo@linux.vnet.ibm.comSigned-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The stripped purgatory does not contain a symtab.  So when looking for
symbols this is done in read-only kexec_purgatory.  Highlight this by
marking the corresponding variables as 'const'.

Link: http://lkml.kernel.org/r/20180321112751.22196-5-prudo@linux.vnet.ibm.comSigned-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The kexec_purgatory buffer is read-only.  Thus all pointers into
kexec_purgatory are read-only, too.  Point this out by explicitly
marking purgatory_info->ehdr as 'const' and update the comments in
purgatory_info.

Link: http://lkml.kernel.org/r/20180321112751.22196-4-prudo@linux.vnet.ibm.comSigned-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Before the purgatory is loaded several checks are done whether the ELF
file in kexec_purgatory is valid or not.  These checks are incomplete.
For example they don't check for the total size of the sections defined
in the section header table or if the entry point actually points into
the purgatory.

On the other hand the purgatory, although an ELF file on its own, is
part of the kernel.  Thus not trusting the purgatory means not trusting
the kernel build itself.

So remove all validity checks on the purgatory and just trust the kernel
build.

Link: http://lkml.kernel.org/r/20180321112751.22196-3-prudo@linux.vnet.ibm.comSigned-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Patch series "kexec_file: Clean up purgatory load", v2.

Following the discussion with Dave and AKASHI, here are the common code
patches extracted from my recent patch set (Add kexec_file_load support
to s390) [1].  The patches were extracted to allow upstream integration
together with AKASHI's common code patches before the arch code gets
adjusted to the new base.

The reason for this series is to prepare common code for adding
kexec_file_load to s390 as well as cleaning up the mis-use of the
sh_offset field during purgatory load.  In detail this series contains:

Patch #1&2: Minor cleanups/fixes.

Patch #3-9: Clean up the purgatory load/relocation code.  Especially
remove the mis-use of the purgatory_info->sechdrs->sh_offset field,
currently holding a pointer into either kexec_purgatory (ro) or
purgatory_buf (rw) depending on the section.  With these patches the
section address will be calculated verbosely and sh_offset will contain
the offset of the section in the stripped purgatory binary
(purgatory_buf).

Patch #10: Allows architectures to set the purgatory load address.  This
patch is important for s390 as the kernel and purgatory have to be
loaded to fixed addresses.  In current code this is impossible as the
purgatory load is opaque to the architecture.

Patch #11: Moves x86 purgatories sha implementation to common lib/
directory to allow reuse in other architectures.

This patch (of 11)

When building the kernel with CONFIG_KEXEC_FILE enabled gcc prints a
compile warning multiple times.

  In file included from <path>/linux/init/initramfs.c:526:0:
  <path>/include/linux/kexec.h:120:9: warning: `struct kimage' declared inside parameter list [enabled by default]
           unsigned long cmdline_len);
           ^

This is because the typedefs for kexec_file_load uses struct kimage
before it is declared.  Fix this by simply forward declaring struct
kimage.

Link: http://lkml.kernel.org/r/20180321112751.22196-2-prudo@linux.vnet.ibm.comSigned-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In the previous patches, commonly-used routines, exclude_mem_range() and
prepare_elf64_headers(), were carved out.  Now place them in kexec
common code.  A prefix "crash_" is given to each of their names to avoid
possible name collisions.

Link: http://lkml.kernel.org/r/20180306102303.9063-8-takahiro.akashi@linaro.orgSigned-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Removing bufp variable in prepare_elf64_headers() makes the code simpler
and more understandable.

Link: http://lkml.kernel.org/r/20180306102303.9063-7-takahiro.akashi@linaro.orgSigned-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

While CRASH_MAX_RANGES (== 16) seems to be good enough, fixed-number
array is not a good idea in general.

In this patch, size of crash_mem buffer is calculated as before and the
buffer is now dynamically allocated.  This change also allows removing
crash_elf_data structure.

Link: http://lkml.kernel.org/r/20180306102303.9063-6-takahiro.akashi@linaro.orgSigned-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The code guarded by CONFIG_X86_64 is necessary on some architectures
which have a dedicated kernel mapping outside of linear memory mapping.
(arm64 is among those.)

In this patch, an additional argument, kernel_map, is added to enable/
disable the code removing #ifdef.

Link: http://lkml.kernel.org/r/20180306102303.9063-5-takahiro.akashi@linaro.orgSigned-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

While prepare_elf64_headers() in x86 looks pretty generic for other
architectures' use, it contains some code which tries to list crash
memory regions by walking through system resources, which is not always
architecture agnostic.  To make this function more generic, the related
code should be purged.

In this patch, prepare_elf64_headers() simply scans crash_mem buffer
passed and add all the listed regions to elf header as a PT_LOAD
segment.  So walk_system_ram_res(prepare_elf64_headers_callback) have
been moved forward before prepare_elf64_headers() where the callback,
prepare_elf64_headers_callback(), is now responsible for filling up
crash_mem buffer.

Meanwhile exclude_elf_header_ranges() used to be called every time in
this callback it is rather redundant and now called only once in
prepare_elf_headers() as well.

Link: http://lkml.kernel.org/r/20180306102303.9063-4-takahiro.akashi@linaro.orgSigned-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

As arch_kexec_kernel_image_{probe,load}(),
arch_kimage_file_post_load_cleanup() and arch_kexec_kernel_verify_sig()
are almost duplicated among architectures, they can be commonalized with
an architecture-defined kexec_file_ops array.  So let's factor them out.

Link: http://lkml.kernel.org/r/20180306102303.9063-3-takahiro.akashi@linaro.orgSigned-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>