Merge tag 'kvm-arm-fixes-for-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master

KVM/ARM Fixes for v4.14

 - Fixes a number of issues with saving/restoring the ITS
 - Fixes a bug in KVM/ARM when branch profiling is enabled in Hyp mode
 - Fixes an emulation bug for 32-bit guests when injecting aborts
  - Fixes a failure to check if a kmalloc succeeds in the ITS emulation

In kvm_apic_set_state() we update the hardware virtualized APIC after
the full APIC state has been overwritten. Do the same, when the full
APIC state has been reset in kvm_lapic_reset().

This updates some hardware state that was previously forgotten, as
far as I can tell. Also, this allows removing some APIC-related reset
code from vmx_vcpu_reset().
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Parts of the posted interrupt descriptor configure host behavior,
such as the notification vector and destination. Overwriting them
with zero as done during vCPU reset breaks posted interrupts.
KVM (re-)writes these fields on certain occasions and belatedly fixes
the situation in many cases. However, if you have a guest configured
with "idle=poll", for example, the fields might stay zero forever.

Do not reset the full descriptor in vmx_vcpu_reset(). Instead,
reset only the outstanding notifications and leave everything
else untouched.
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

kvm does not support setting the RTC, so the correct result is -ENODEV.
Returning -1 will cause sync_cmos_clock to keep trying to set the RTC
every second.
Signed-off-by: Jason Gunthorpe <jgg@ziepe.ca>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

At the moment we don't properly check the GITS_BASER<n>.Valid
bit before saving the collection and device tables.

On vgic_its_save_collection_table() we use the GITS_BASER gpa
field whereas the Valid bit should be used.

On vgic_its_save_device_tables() there is no check. This can
cause various bugs, among which a subsequent fault when accessing
the table in guest memory.

Let's systematically check the Valid bit before doing anything.

We also uniformize the code between save and restore.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

The spec says it is UNPREDICTABLE to enable the ITS
if any of the following conditions are true:

- GITS_CBASER.Valid == 0.
- GITS_BASER<n>.Valid == 0, for any GITS_BASER<n> register
  where the Type field indicates Device.
- GITS_BASER<n>.Valid == 0, for any GITS_BASER<n> register
  where the Type field indicates Interrupt Collection and
  GITS_TYPER.HCC == 0.

In that case, let's keep the ITS disabled.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reported-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

vgic_its_restore_cte returns +1 if the collection table entry
is valid and properly decoded. As a consequence, if the
collection table is fully filled with valid data that are
decoded without error, vgic_its_restore_collection_table()
returns +1. This is wrong.

Let's return 0 in that case.

Fixes: ea1ad53e (KVM: arm64: vgic-its: Collection table save/restore)
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

If ITT only contains invalid entries, vgic_its_restore_itt
returns 1 and this is considered as an an error in
vgic_its_restore_dte.

Also in case the device table only contains invalid entries,
the table restore fails and this is not correct.

This patch fixes those 2 issues:
- vgic_its_restore_itt now returns <= 0 values. If all
  ITEs are invalid, this is considered as successful.
- vgic_its_restore_device_tables also returns <= 0 values.

We also simplify the returned value computation in
handle_l1_dte.
Signed-off-by: wanghaibin <wanghaibin.wang@huawei.com>
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

When HYP code runs into branch profiling code, it attempts to jump to
unmapped memory, causing a HYP Panic.

Disable the branch profiling for code designed to run at HYP mode.
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

KVM is being a bit too optimistic, Hyp mode is said to be initialized
when Hyp segments have only been mapped.

Notify KVM's successful initialization only once it is really fully
initialized.
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

When a exception is trapped to EL2, hardware uses  ELR_ELx to hold
the current fault instruction address. If KVM wants to inject a
abort to 32 bit guest, it needs to set the LR register for the
guest to emulate this abort happened in the guest. Because ARM32
architecture is pipelined execution, so the LR value has an offset to
the fault instruction address.

The offsets applied to Link value for exceptions as shown below,
which should be added for the ARM32 link register(LR).

Table taken from ARMv8 ARM DDI0487B-B, table G1-10:
Exception			Offset, for PE state of:
				A32 	  T32
Undefined Instruction 		+4 	  +2
Prefetch Abort 			+4 	  +4
Data Abort 			+8 	  +8
IRQ or FIQ 			+4 	  +4

  [ Removed unused variables in inject_abt to avoid compile warnings.
    -- Christoffer ]

Cc: <stable@vger.kernel.org>
Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
Tested-by: Haibin Zhang <zhanghaibin7@huawei.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>

Fix potential host oops and hangs.

On POWER9 systems, we push the VCPU context onto the XIVE (eXternal
Interrupt Virtualization Engine) hardware when entering a guest,
and pull the context off the XIVE when exiting the guest.  The push
is done with cache-inhibited stores, and the pull with cache-inhibited
loads.

Testing has revealed that it is possible (though very rare) for
the stores to get reordered with the loads so that we end up with the
guest VCPU context still loaded on the XIVE after we have exited the
guest.  When that happens, it is possible for the same VCPU context
to then get loaded on another CPU, which causes the machine to
checkstop.

To fix this, we add I/O barrier instructions (eieio) before and
after the push and pull operations.  As partial compensation for the
potential slowdown caused by the extra barriers, we remove the eieio
instructions between the two stores in the push operation, and between
the two loads in the pull operation.  (The architecture requires
loads to cache-inhibited, guarded storage to be kept in order, and
requires stores to cache-inhibited, guarded storage likewise to be
kept in order, but allows such loads and stores to be reordered with
respect to each other.)
Reported-by: Carol L Soto <clsoto@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

Pull char/misc driver fixes from Greg KH:
 "Here are 4 patches to resolve some char/misc driver issues found these
  past weeks.

  One of them is a mei bugfix and another is a new mei device id. There
  is also a hyper-v fix for a reported issue, and a binder issue fix for
  a problem reported by a few people.

  All of these have been in my tree for a while, I don't know if
  linux-next is really testing much this month. But 0-day is happy with
  them :)"

* tag 'char-misc-4.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  binder: fix use-after-free in binder_transaction()
  Drivers: hv: vmbus: Fix bugs in rescind handling
  mei: me: add gemini lake devices id
  mei: always use domain runtime pm callbacks.

Pull USB fixes from Greg KH:
 "Here are a handful of USB driver fixes for 4.14-rc5.

  There is the "usual" usb-serial fixes and device ids, USB gadget
  fixes, and some more fixes found by the fuzz testing that is happening
  on the USB layer right now.

  All of these have been in my tree this week with no reported issues"

* tag 'usb-4.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: usbtest: fix NULL pointer dereference
  usb: gadget: configfs: Fix memory leak of interface directory data
  usb: gadget: composite: Fix use-after-free in usb_composite_overwrite_options
  usb: misc: usbtest: Fix overflow in usbtest_do_ioctl()
  usb: renesas_usbhs: Fix DMAC sequence for receiving zero-length packet
  USB: dummy-hcd: Fix deadlock caused by disconnect detection
  usb: phy: tegra: Fix phy suspend for UDC
  USB: serial: console: fix use-after-free after failed setup
  USB: serial: console: fix use-after-free on disconnect
  USB: serial: qcserial: add Dell DW5818, DW5819
  USB: serial: cp210x: add support for ELV TFD500
  USB: serial: cp210x: fix partnum regression
  USB: serial: option: add support for TP-Link LTE module
  USB: serial: ftdi_sio: add id for Cypress WICED dev board

Pull dmaengine fixes from Vinod Koul:
 "Here are fixes for this round

   - fix spinlock usage amd fifo response for altera driver

   - fix ti crossbar race condition

   - fix edma memcpy align"

* tag 'dmaengine-fix-4.14-rc5' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: altera: fix spinlock usage
  dmaengine: altera: fix response FIFO emptying
  dmaengine: ti-dma-crossbar: Fix possible race condition with dma_inuse
  dmaengine: edma: Align the memcpy acnt array size with the transfer

Pull x86 fixes from Ingo Molnar:
 "A landry list of fixes:

   - fix reboot breakage on some PCID-enabled system

   - fix crashes/hangs on some PCID-enabled systems

   - fix microcode loading on certain older CPUs

   - various unwinder fixes

   - extend an APIC quirk to more hardware systems and disable APIC
     related warning on virtualized systems

   - various Hyper-V fixes

   - a macro definition robustness fix

   - remove jprobes IRQ disabling

   - various mem-encryption fixes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/microcode: Do the family check first
  x86/mm: Flush more aggressively in lazy TLB mode
  x86/apic: Update TSC_DEADLINE quirk with additional SKX stepping
  x86/apic: Silence "FW_BUG TSC_DEADLINE disabled due to Errata" on hypervisors
  x86/mm: Disable various instrumentations of mm/mem_encrypt.c and mm/tlb.c
  x86/hyperv: Fix hypercalls with extended CPU ranges for TLB flushing
  x86/hyperv: Don't use percpu areas for pcpu_flush/pcpu_flush_ex structures
  x86/hyperv: Clear vCPU banks between calls to avoid flushing unneeded vCPUs
  x86/unwind: Disable unwinder warnings on 32-bit
  x86/unwind: Align stack pointer in unwinder dump
  x86/unwind: Use MSB for frame pointer encoding on 32-bit
  x86/unwind: Fix dereference of untrusted pointer
  x86/alternatives: Fix alt_max_short macro to really be a max()
  x86/mm/64: Fix reboot interaction with CR4.PCIDE
  kprobes/x86: Remove IRQ disabling from jprobe handlers
  kprobes/x86: Set up frame pointer in kprobe trampoline

Pull scheduler fixes from Ingo Molnar:
 "Three fixes that address an SMP balancing performance regression"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Ensure load_balance() respects the active_mask
  sched/core: Address more wake_affine() regressions
  sched/core: Fix wake_affine() performance regression

Pull RAS fixes from Ingo Molnar:
 "A boot parameter fix, plus a header export fix"

* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Hide mca_cfg
  RAS/CEC: Use the right length for "cec_disable"

Pull perf fixes from Ingo Molnar:
 "Some tooling fixes plus three kernel fixes: a memory leak fix, a
  statistics fix and a crash fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/uncore: Fix memory leaks on allocation failures
  perf/core: Fix cgroup time when scheduling descendants
  perf/core: Avoid freeing static PMU contexts when PMU is unregistered
  tools include uapi bpf.h: Sync kernel ABI header with tooling header
  perf pmu: Unbreak perf record for arm/arm64 with events with explicit PMU
  perf script: Add missing separator for "-F ip,brstack" (and brstackoff)
  perf callchain: Compare dsos (as well) for CCKEY_FUNCTION

Pull locking fixes from Ingo Molnar:
 "Two lockdep fixes for bugs introduced by the cross-release dependency
  tracking feature - plus a commit that disables it because performance
  regressed in an absymal fashion on some systems"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/lockdep: Disable cross-release features for now
  locking/selftest: Avoid false BUG report
  locking/lockdep: Fix stacktrace mess

Pull irq fixes from Ingo Molnar:
 "A CPU hotplug related fix, plus two related sanity checks"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/cpuhotplug: Enforce affinity setting on startup of managed irqs
  genirq/cpuhotplug: Add sanity check for effective affinity mask
  genirq: Warn when effective affinity is not updated

Pull objtool fix from Ingo Molnar:
 "A single objtool fix: avoid silently broken ORC debuginfo builds and
  error out instead"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Upgrade libelf-devel warning to error for CONFIG_ORC_UNWINDER

On CPUs like AMD's Geode, for example, we shouldn't even try to load
microcode because they do not support the modern microcode loading
interface.

However, we do the family check *after* the other checks whether the
loader has been disabled on the command line or whether we're running in
a guest.

So move the family checks first in order to exit early if we're being
loaded on an unsupported family.
Reported-and-tested-by: Sven Glodowski <glodi1@arcor.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org> # 4.11..
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://bugzilla.suse.com/show_bug.cgi?id=1061396
Link: http://lkml.kernel.org/r/20171012112316.977-1-bp@alien8.deSigned-off-by: Ingo Molnar <mingo@kernel.org>

Johan Hovold reported a big lockdep slowdown on his system, caused by lockdep:

> I had noticed that the BeagleBone Black boot time appeared to have
> increased significantly with 4.14 and yesterday I finally had time to
> investigate it.
>
> Boot time (from "Linux version" to login prompt) had in fact doubled
> since 4.13 where it took 17 seconds (with my current config) compared to
> the 35 seconds I now see with 4.14-rc4.
>
> I quick bisect pointed to lockdep and specifically the following commit:
>
>	28a903f6 ("locking/lockdep: Handle non(or multi)-acquisition of a crosslock")

Because the final v4.14 release is close, disable the cross-release lockdep
features for now.
Bisected-by: Johan Hovold <johan@kernel.org>
Debugged-by: Johan Hovold <johan@kernel.org>
Reported-by: Johan Hovold <johan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Lindgren <tony@atomide.com>
Cc: kernel-team@lge.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mm@kvack.org
Cc: linux-omap@vger.kernel.org
Link: http://lkml.kernel.org/r/20171014072659.f2yr6mhm5ha3eou7@gmail.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Pull MIPS fixes from Ralf Baechle:
 "More MIPS fixes for 4.14:

   - Loongson 1: Set the default number of RX and TX queues to
     accomodate for recent changes of stmmac driver.

   - BPF: Fix uninitialised target compiler error.

   - Fix cmpxchg on 32 bit signed ints for 64 bit kernels with
     !kernel_uses_llsc

   - Fix generic-board-config.sh for builds using O=

   - Remove pr_err() calls from fpu_emu() for a case which is not a
     kernel error"

* '4.14-fixes' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: math-emu: Remove pr_err() calls from fpu_emu()
  MIPS: Fix generic-board-config.sh for builds using O=
  MIPS: Fix cmpxchg on 32b signed ints for 64b kernel with !kernel_uses_llsc
  MIPS: loongson1: set default number of rx and tx queues for stmmac
  MIPS: bpf: Fix uninitialised target compiler error

Since commit:

  94b1b03b ("x86/mm: Rework lazy TLB mode and TLB freshness tracking")

x86's lazy TLB mode has been all the way lazy: when running a kernel thread
(including the idle thread), the kernel keeps using the last user mm's
page tables without attempting to maintain user TLB coherence at all.

From a pure semantic perspective, this is fine -- kernel threads won't
attempt to access user pages, so having stale TLB entries doesn't matter.

Unfortunately, I forgot about a subtlety.  By skipping TLB flushes,
we also allow any paging-structure caches that may exist on the CPU
to become incoherent.  This means that we can have a
paging-structure cache entry that references a freed page table, and
the CPU is within its rights to do a speculative page walk starting
at the freed page table.

I can imagine this causing two different problems:

 - A speculative page walk starting from a bogus page table could read
   IO addresses.  I haven't seen any reports of this causing problems.

 - A speculative page walk that involves a bogus page table can install
   garbage in the TLB.  Such garbage would always be at a user VA, but
   some AMD CPUs have logic that triggers a machine check when it notices
   these bogus entries.  I've seen a couple reports of this.

Boris further explains the failure mode:

> It is actually more of an optimization which assumes that paging-structure
> entries are in WB DRAM:
>
> "TlbCacheDis: cacheable memory disable. Read-write. 0=Enables
> performance optimization that assumes PML4, PDP, PDE, and PTE entries
> are in cacheable WB-DRAM; memory type checks may be bypassed, and
> addresses outside of WB-DRAM may result in undefined behavior or NB
> protocol errors. 1=Disables performance optimization and allows PML4,
> PDP, PDE and PTE entries to be in any memory type. Operating systems
> that maintain page tables in memory types other than WB- DRAM must set
> TlbCacheDis to insure proper operation."
>
> The MCE generated is an NB protocol error to signal that
>
> "Link: A specific coherent-only packet from a CPU was issued to an
> IO link. This may be caused by software which addresses page table
> structures in a memory type other than cacheable WB-DRAM without
> properly configuring MSRC001_0015[TlbCacheDis]. This may occur, for
> example, when page table structure addresses are above top of memory. In
> such cases, the NB will generate an MCE if it sees a mismatch between
> the memory operation generated by the core and the link type."
>
> I'm assuming coherent-only packets don't go out on IO links, thus the
> error.

To fix this, reinstate TLB coherence in lazy mode.  With this patch
applied, we do it in one of two ways:

 - If we have PCID, we simply switch back to init_mm's page tables
   when we enter a kernel thread -- this seems to be quite cheap
   except for the cost of serializing the CPU.

 - If we don't have PCID, then we set a flag and switch to init_mm
   the first time we would otherwise need to flush the TLB.

The /sys/kernel/debug/x86/tlb_use_lazy_mode debug switch can be changed
to override the default mode for benchmarking.

In theory, we could optimize this better by only flushing the TLB in
lazy CPUs when a page table is freed.  Doing that would require
auditing the mm code to make sure that all page table freeing goes
through tlb_remove_page() as well as reworking some data structures
to implement the improved flush logic.
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Reported-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Johannes Hirte <johannes.hirte@datenkhaos.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Roman Kagan <rkagan@virtuozzo.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 94b1b03b ("x86/mm: Rework lazy TLB mode and TLB freshness tracking")
Link: http://lkml.kernel.org/r/20171009170231.fkpraqokz6e4zeco@pd.tnicSigned-off-by: Ingo Molnar <mingo@kernel.org>

Pull drm fixes from Dave Airlie:
 "Couple of the arm people seem to wake up so this has imx and msm
  fixes, along with a bunch of i915 stable bounds fixes and an amdgpu
  regression fix.

  All seems pretty okay for now"

* tag 'drm-fixes-for-v4.14-rc5' of git://people.freedesktop.org/~airlied/linux:
  drm/msm: fix _NO_IMPLICIT fencing case
  drm/msm: fix error path cleanup
  drm/msm/mdp5: Remove extra pm_runtime_put call in mdp5_crtc_cursor_set()
  drm/msm/dsi: Use correct pm_runtime_put variant during host_init
  drm/msm: fix return value check in _msm_gem_kernel_new()
  drm/msm: use proper memory barriers for updating tail/head
  drm/msm/mdp5: add missing max size for 8x74 v1
  drm/amdgpu: fix placement flags in amdgpu_ttm_bind
  drm/i915/bios: parse DDI ports also for CHV for HDMI DDC pin and DP AUX channel
  gpu: ipu-v3: pre: implement workaround for ERR009624
  gpu: ipu-v3: prg: wait for double buffers to be filled on channel startup
  gpu: ipu-v3: Allow channel burst locking on i.MX6 only
  drm/i915: Read timings from the correct transcoder in intel_crtc_mode_get()
  drm/i915: Order two completing nop_submit_request
  drm/i915: Silence compiler warning for hsw_power_well_enable()
  drm/i915: Use crtc_state_is_legacy_gamma in intel_color_check
  drm/i915/edp: Increase the T12 delay quirk to 1300ms
  drm/i915/edp: Get the Panel Power Off timestamp after panel is off
  sync_file: Return consistent status in SYNC_IOC_FILE_INFO
  drm/atomic: Unref duplicated drm_atomic_state in drm_atomic_helper_resume()

kvmppc_gpa_to_ua() accesses KVM memory slot array via
srcu_dereference_check() and this produces warnings from RCU like below.

This extends the existing srcu_read_lock/unlock to cover that
kvmppc_gpa_to_ua() as well.

We did not hit this before as this lock is not needed for the realmode
handlers and hash guests would use the realmode path all the time;
however the radix guests are always redirected to the virtual mode
handlers and hence the warning.

[   68.253798] ./include/linux/kvm_host.h:575 suspicious rcu_dereference_check() usage!
[   68.253799]
               other info that might help us debug this:

[   68.253802]
               rcu_scheduler_active = 2, debug_locks = 1
[   68.253804] 1 lock held by qemu-system-ppc/6413:
[   68.253806]  #0:  (&vcpu->mutex){+.+.}, at: [<c00800000e3c22f4>] vcpu_load+0x3c/0xc0 [kvm]
[   68.253826]
               stack backtrace:
[   68.253830] CPU: 92 PID: 6413 Comm: qemu-system-ppc Tainted: G        W       4.14.0-rc3-00553-g432dcba58e9c-dirty #72
[   68.253833] Call Trace:
[   68.253839] [c000000fd3d9f790] [c000000000b7fcc8] dump_stack+0xe8/0x160 (unreliable)
[   68.253845] [c000000fd3d9f7d0] [c0000000001924c0] lockdep_rcu_suspicious+0x110/0x180
[   68.253851] [c000000fd3d9f850] [c0000000000e825c] kvmppc_gpa_to_ua+0x26c/0x2b0
[   68.253858] [c000000fd3d9f8b0] [c00800000e3e1984] kvmppc_h_put_tce+0x12c/0x2a0 [kvm]

Fixes: 121f80ba ("KVM: PPC: VFIO: Add in-kernel acceleration for VFIO")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

- Add another case where msgsync is required.
- Required barrier sequence for global doorbells is msgsync ; lwsync

When msgsnd is used for IPIs to other cores, msgsync must be executed by
the target to order stores performed on the source before its msgsnd
(provided the source executes the appropriate sync).

Fixes: 1704a81c ("KVM: PPC: Book3S HV: Use msgsnd for IPIs to other cores on POWER9")
Cc: stable@vger.kernel.org # v4.10+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

The following program causes a kernel oops:

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/kvm.h>

main()
{
    int fd = open("/dev/kvm", O_RDWR);
    ioctl(fd, KVM_CHECK_EXTENSION, KVM_CAP_PPC_HTM);
}

This happens because when using the global KVM fd with
KVM_CHECK_EXTENSION, kvm_vm_ioctl_check_extension() gets
called with a NULL kvm argument, which gets dereferenced
in is_kvmppc_hv_enabled(). Spotted while reading the code.

Let's use the hv_enabled fallback variable, like everywhere
else in this function.

Fixes: 23528bb2 ("KVM: PPC: Introduce KVM_CAP_PPC_HTM")
Cc: stable@vger.kernel.org # v4.7+
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

Merge tag 'drm-intel-fixes-2017-10-11' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

drm/i915 fixes for 4.14-rc5:

Three fixes for stable:

- Use crtc_state_is_legacy_gamma in intel_color_check (Maarten)
- Read timings from the correct transcoder (Ville).
- Fix HDMI on BSW (Jani).

Other fixes:

- eDP fixes (Manasi)
- Silence compiler warnings (Chris)
- Order two completing nop_submit_request (Chris)

* tag 'drm-intel-fixes-2017-10-11' of git://anongit.freedesktop.org/drm/drm-intel:
  drm/i915/bios: parse DDI ports also for CHV for HDMI DDC pin and DP AUX channel
  drm/i915: Read timings from the correct transcoder in intel_crtc_mode_get()
  drm/i915: Order two completing nop_submit_request
  drm/i915: Silence compiler warning for hsw_power_well_enable()
  drm/i915: Use crtc_state_is_legacy_gamma in intel_color_check
  drm/i915/edp: Increase the T12 delay quirk to 1300ms
  drm/i915/edp: Get the Panel Power Off timestamp after panel is off

bunch of msm fixes

* 'msm-fixes-4.14-rc4' of git://people.freedesktop.org/~robclark/linux:
  drm/msm: fix _NO_IMPLICIT fencing case
  drm/msm: fix error path cleanup
  drm/msm/mdp5: Remove extra pm_runtime_put call in mdp5_crtc_cursor_set()
  drm/msm/dsi: Use correct pm_runtime_put variant during host_init
  drm/msm: fix return value check in _msm_gem_kernel_new()
  drm/msm: use proper memory barriers for updating tail/head
  drm/msm/mdp5: add missing max size for 8x74 v1

Merge misc fixes from Andrew Morton:
 "18 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm, swap: use page-cluster as max window of VMA based swap readahead
  mm: page_vma_mapped: ensure pmd is loaded with READ_ONCE outside of lock
  kmemleak: clear stale pointers from task stacks
  fs/binfmt_misc.c: node could be NULL when evicting inode
  fs/mpage.c: fix mpage_writepage() for pages with buffers
  linux/kernel.h: add/correct kernel-doc notation
  tty: fall back to N_NULL if switching to N_TTY fails during hangup
  Revert "vmalloc: back off when the current task is killed"
  mm/cma.c: take __GFP_NOWARN into account in cma_alloc()
  scripts/kallsyms.c: ignore symbol type 'n'
  userfaultfd: selftest: exercise -EEXIST only in background transfer
  mm: only display online cpus of the numa node
  mm: remove unnecessary WARN_ONCE in page_vma_mapped_walk().
  mm/mempolicy: fix NUMA_INTERLEAVE_HIT counter
  include/linux/of.h: provide of_n_{addr,size}_cells wrappers for !CONFIG_OF
  mm/madvise.c: add description for MADV_WIPEONFORK and MADV_KEEPONFORK
  lib/Kconfig.debug: kernel hacking menu: runtime testing: keep tests together
  mm/migrate: fix indexing bug (off by one) and avoid out of bound access

When the VMA based swap readahead was introduced, a new knob

  /sys/kernel/mm/swap/vma_ra_max_order

was added as the max window of VMA swap readahead.  This is to make it
possible to use different max window for VMA based readahead and
original physical readahead.  But Minchan Kim pointed out that this will
cause a regression because setting page-cluster sysctl to zero cannot
disable swap readahead with the change.

To fix the regression, the page-cluster sysctl is used as the max window
of both the VMA based swap readahead and original physical swap
readahead.  If more fine grained control is needed in the future, more
knobs can be added as the subordinate knobs of the page-cluster sysctl.

The vma_ra_max_order knob is deleted.  Because the knob was introduced
in v4.14-rc1, and this patch is targeting being merged before v4.14
releasing, there should be no existing users of this newly added ABI.

Link: http://lkml.kernel.org/r/20171011070847.16003-1-ying.huang@intel.com
Fixes: ec560175 ("mm, swap: VMA based swap readahead")
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reported-by: Minchan Kim <minchan@kernel.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Tim Chen <tim.c.chen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Loading the pmd without holding the pmd_lock exposes us to races with
concurrent updaters of the page tables but, worse still, it also allows
the compiler to cache the pmd value in a register and reuse it later on,
even if we've performed a READ_ONCE in between and seen a more recent
value.

In the case of page_vma_mapped_walk, this leads to the following crash
when the pmd loaded for the initial pmd_trans_huge check is all zeroes
and a subsequent valid table entry is loaded by check_pmd.  We then
proceed into map_pte, but the compiler re-uses the zero entry inside
pte_offset_map, resulting in a junk pointer being installed in
pvmw->pte:

  PC is at check_pte+0x20/0x170
  LR is at page_vma_mapped_walk+0x2e0/0x540
  [...]
  Process doio (pid: 2463, stack limit = 0xffff00000f2e8000)
  Call trace:
    check_pte+0x20/0x170
    page_vma_mapped_walk+0x2e0/0x540
    page_mkclean_one+0xac/0x278
    rmap_walk_file+0xf0/0x238
    rmap_walk+0x64/0xa0
    page_mkclean+0x90/0xa8
    clear_page_dirty_for_io+0x84/0x2a8
    mpage_submit_page+0x34/0x98
    mpage_process_page_bufs+0x164/0x170
    mpage_prepare_extent_to_map+0x134/0x2b8
    ext4_writepages+0x484/0xe30
    do_writepages+0x44/0xe8
    __filemap_fdatawrite_range+0xbc/0x110
    file_write_and_wait_range+0x48/0xd8
    ext4_sync_file+0x80/0x4b8
    vfs_fsync_range+0x64/0xc0
    SyS_msync+0x194/0x1e8

This patch fixes the problem by ensuring that READ_ONCE is used before
the initial checks on the pmd, and this value is subsequently used when
checking whether or not the pmd is present.  pmd_check is removed and
the pmd_present check is inlined directly.

Link: http://lkml.kernel.org/r/1507222630-5839-1-git-send-email-will.deacon@arm.com
Fixes: f27176cf ("mm: convert page_mkclean_one() to use page_vma_mapped_walk()")
Signed-off-by: Will Deacon <will.deacon@arm.com>
Tested-by: Yury Norov <ynorov@caviumnetworks.com>
Tested-by: Richard Ruigrok <rruigrok@codeaurora.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Kmemleak considers any pointers on task stacks as references.  This
patch clears newly allocated and reused vmap stacks.

Link: http://lkml.kernel.org/r/150728990124.744199.8403409836394318684.stgit@buzzSigned-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

inode->i_private is assigned by a Node pointer only after registering a
new binary format, so it could be NULL if inode was created by
bm_fill_super() (or iput() was called by the error path in
bm_register_write()), and this could result in NULL pointer dereference
when evicting such an inode.  e.g.  mount binfmt_misc filesystem then
umount it immediately:

  mount -t binfmt_misc binfmt_misc /proc/sys/fs/binfmt_misc
  umount /proc/sys/fs/binfmt_misc

will result in

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000013
  IP: bm_evict_inode+0x16/0x40 [binfmt_misc]
  ...
  Call Trace:
   evict+0xd3/0x1a0
   iput+0x17d/0x1d0
   dentry_unlink_inode+0xb9/0xf0
   __dentry_kill+0xc7/0x170
   shrink_dentry_list+0x122/0x280
   shrink_dcache_parent+0x39/0x90
   do_one_tree+0x12/0x40
   shrink_dcache_for_umount+0x2d/0x90
   generic_shutdown_super+0x1f/0x120
   kill_litter_super+0x29/0x40
   deactivate_locked_super+0x43/0x70
   deactivate_super+0x45/0x60
   cleanup_mnt+0x3f/0x70
   __cleanup_mnt+0x12/0x20
   task_work_run+0x86/0xa0
   exit_to_usermode_loop+0x6d/0x99
   syscall_return_slowpath+0xba/0xf0
   entry_SYSCALL_64_fastpath+0xa3/0xa

Fix it by making sure Node (e) is not NULL.

Link: http://lkml.kernel.org/r/20171010100642.31786-1-eguan@redhat.com
Fixes: 83f91827 ("exec: binfmt_misc: shift filp_close(interp_file) from kill_node() to bm_evict_inode()")
Signed-off-by: Eryu Guan <eguan@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When using FAT on a block device which supports rw_page, we can hit
BUG_ON(!PageLocked(page)) in try_to_free_buffers().  This is because we
call clean_buffers() after unlocking the page we've written.  Introduce
a new clean_page_buffers() which cleans all buffers associated with a
page and call it from within bdev_write_page().

[akpm@linux-foundation.org: s/PAGE_SIZE/~0U/ per Linus and Matthew]
Link: http://lkml.kernel.org/r/20171006211541.GA7409@bombadil.infradead.orgSigned-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reported-by: Toshi Kani <toshi.kani@hpe.com>
Reported-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Tested-by: Toshi Kani <toshi.kani@hpe.com>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>