Current we store the userspace r1 to PACATMSCRATCH before finally
saving it to the thread struct.

In theory an exception could be taken here (like a machine check or
SLB miss) that could write PACATMSCRATCH and hence corrupt the
userspace r1. The SLB fault currently doesn't touch PACATMSCRATCH, but
others do.

We've never actually seen this happen but it's theoretically
possible. Either way, the code is fragile as it is.

This patch saves r1 to the kernel stack (which can't fault) before we
turn MSR[RI] back on. PACATMSCRATCH is still used but only with
MSR[RI] off. We then copy r1 from the kernel stack to the thread
struct once we have MSR[RI] back on.
Suggested-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

When we treclaim we store the userspace checkpointed r13 to a scratch
SPR and then later save the scratch SPR to the user thread struct.

Unfortunately, this doesn't work as accessing the user thread struct
can take an SLB fault and the SLB fault handler will write the same
scratch SPRG that now contains the userspace r13.

To fix this, we store r13 to the kernel stack (which can't fault)
before we access the user thread struct.

Found by running P8 guest + powervm + disable_1tb_segments + TM. Seen
as a random userspace segfault with r13 looking like a kernel address.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

After migration of a powerpc LPAR, the kernel executes code to
update the system state to reflect new platform characteristics.

Such changes include modifications to device tree properties provided
to the system by PHYP. Property notifications received by the
post_mobility_fixup() code are passed along to the kernel in general
through a call to of_update_property() which in turn passes such
events back to all modules through entries like the '.notifier_call'
function within the NUMA module.

When the NUMA module updates its state, it resets its event timer. If
this occurs after a previous call to stop_topology_update() or on a
system without VPHN enabled, the code runs into an unitialized timer
structure and crashes. This patch adds a safety check along this path
toward the problem code.

An example crash log is as follows.

  ibmvscsi 30000081: Re-enabling adapter!
  ------------[ cut here ]------------
  kernel BUG at kernel/time/timer.c:958!
  Oops: Exception in kernel mode, sig: 5 [#1]
  LE SMP NR_CPUS=2048 NUMA pSeries
  Modules linked in: nfsv3 nfs_acl nfs tcp_diag udp_diag inet_diag lockd unix_diag af_packet_diag netlink_diag grace fscache sunrpc xts vmx_crypto pseries_rng sg binfmt_misc ip_tables xfs libcrc32c sd_mod ibmvscsi ibmveth scsi_transport_srp dm_mirror dm_region_hash dm_log dm_mod
  CPU: 11 PID: 3067 Comm: drmgr Not tainted 4.17.0+ #179
  ...
  NIP mod_timer+0x4c/0x400
  LR  reset_topology_timer+0x40/0x60
  Call Trace:
    0xc0000003f9407830 (unreliable)
    reset_topology_timer+0x40/0x60
    dt_update_callback+0x100/0x120
    notifier_call_chain+0x90/0x100
    __blocking_notifier_call_chain+0x60/0x90
    of_property_notify+0x90/0xd0
    of_update_property+0x104/0x150
    update_dt_property+0xdc/0x1f0
    pseries_devicetree_update+0x2d0/0x510
    post_mobility_fixup+0x7c/0xf0
    migration_store+0xa4/0xc0
    kobj_attr_store+0x30/0x60
    sysfs_kf_write+0x64/0xa0
    kernfs_fop_write+0x16c/0x240
    __vfs_write+0x40/0x200
    vfs_write+0xc8/0x240
    ksys_write+0x5c/0x100
    system_call+0x58/0x6c

Fixes: 5d88aa85 ("powerpc/pseries: Update CPU maps when device tree is updated")
Cc: stable@vger.kernel.org # v3.10+
Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

scan_pkey_feature() uses of_property_read_u32_array() to read the
ibm,processor-storage-keys property and calls be32_to_cpu() on the
value it gets. The problem is that of_property_read_u32_array() already
returns the value converted to the CPU byte order.

The value of pkeys_total ends up more or less sane because there's a min()
call in pkey_initialize() which reduces pkeys_total to 32. So in practice
the kernel ignores the fact that the hypervisor reserved one key for
itself (the device tree advertises 31 keys in my test VM).

This is wrong, but the effect in practice is that when a process tries to
allocate the 32nd key, it gets an -EINVAL error instead of -ENOSPC which
would indicate that there aren't any keys available

Fixes: cf43d3b2 ("powerpc: Enable pkey subsystem")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

On little endian platforms, csum_ipv6_magic() keeps len and proto in
CPU byte order. This generates a bad results leading to ICMPv6 packets
from other hosts being dropped by powerpc64le platforms.

In order to fix this, len and proto should be converted to network
byte order ie bigendian byte order. However checksumming 0x12345678
and 0x56341278 provide the exact same result so it is enough to
rotate the sum of len and proto by 1 byte.

PPC32 only support bigendian so the fix is needed for PPC64 only

Fixes: e9c4943a ("powerpc: Implement csum_ipv6_magic in assembly")
Reported-by: Jianlin Shi <jishi@redhat.com>
Reported-by: Xin Long <lucien.xin@gmail.com>
Cc: <stable@vger.kernel.org> # 4.18+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Tested-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

mpe: This was fixed originally in commit d3d4ffaa
("powerpc/powernv/ioda2: Reduce upper limit for DMA window size"), but
contrary to what the merge commit says was inadvertently lost by me in
commit ce57c661 ("Merge branch 'topic/ppc-kvm' into next") which
brought in changes that moved the code to a new file. So reapply it to
the new file.

Original commit message follows:

We use PHB in mode1 which uses bit 59 to select a correct DMA window.
However there is mode2 which uses bits 59:55 and allows up to 32 DMA
windows per a PE.

Even though documentation does not clearly specify that, it seems that
the actual hardware does not support bits 59:55 even in mode1, in
other words we can create a window as big as 1<<58 but DMA simply
won't work.

This reduces the upper limit from 59 to 55 bits to let the userspace
know about the hardware limits.

Fixes: ce57c661 ("Merge branch 'topic/ppc-kvm' into next")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This stops us from doing code patching in init sections after they've
been freed.

In this chain:
  kvm_guest_init() ->
    kvm_use_magic_page() ->
      fault_in_pages_readable() ->
	 __get_user() ->
	   __get_user_nocheck() ->
	     barrier_nospec();

We have a code patching location at barrier_nospec() and
kvm_guest_init() is an init function. This whole chain gets inlined,
so when we free the init section (hence kvm_guest_init()), this code
goes away and hence should no longer be patched.

We seen this as userspace memory corruption when using a memory
checker while doing partition migration testing on powervm (this
starts the code patching post migration via
/sys/kernel/mobility/migration). In theory, it could also happen when
using /sys/kernel/debug/powerpc/barrier_nospec.

Cc: stable@vger.kernel.org # 4.13+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

When we come into the softpatch handler (0x1500), we use r11 to store
the HSRR0 for later use by the denorm handler.

We also use the softpatch handler for the TM workarounds for
POWER9. Unfortunately, in kvmppc_interrupt_hv we later store r11 out
to the vcpu assuming it's still what we got from userspace.

This causes r11 to be corrupted in the VCPU and hence when we restore
the guest, we get a corrupted r11. We've seen this when running TM
tests inside guests on P9.

This fixes the problem by only touching r11 in the denorm case.

Fixes: 4bb3c7a0 ("KVM: PPC: Book3S HV: Work around transactional memory bugs in POWER9")
Cc: <stable@vger.kernel.org> # 4.17+
Test-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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

   - Prevent multiplication result truncation on 32bit. Introduced with
     the early timestamp reworrk.

   - Ensure microcode revision storage to be consistent under all
     circumstances

   - Prevent write tearing of PTEs

   - Prevent confusion of user and kernel reegisters when dumping fatal
     signals verbosely

   - Make an error return value in a failure path of the vector
     allocation negative. Returning EINVAL might the caller assume
     success and causes further wreckage.

   - A trivial kernel doc warning fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Use WRITE_ONCE() when setting PTEs
  x86/apic/vector: Make error return value negative
  x86/process: Don't mix user/kernel regs in 64bit __show_regs()
  x86/tsc: Prevent result truncation on 32bit
  x86: Fix kernel-doc atomic.h warnings
  x86/microcode: Update the new microcode revision unconditionally
  x86/microcode: Make sure boot_cpu_data.microcode is up-to-date

Pull timekeeping fixes from Thomas Gleixner:
 "Two fixes for timekeeping:

   - Revert to the previous kthread based update, which is unfortunately
     required due to lock ordering issues. The removal caused boot
     failures on old Core2 machines. Add a proper comment why the thread
     needs to stay to prevent accidental removal in the future.

   - Fix a silly typo in a function declaration"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: Revert "Remove kthread"
  timekeeping: Fix declaration of read_persistent_wall_and_boot_offset()

Pull irqchip fix from Thomas Gleixner:
 "A single fix to prevent allocating excessive memory in the GIC/ITS
  driver.

  While the subject of the patch might suggest otherwise this is a real
  fix as some SoCs exceed the memory allocation limits and fail to boot"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic-v3-its: Cap lpi_id_bits to reduce memory footprint

Pull cpu hotplug fixes from Thomas Gleixner:
 "Two fixes for the hotplug state machine code:

   - Move the misplaces smb() in the hotplug thread function to the
     proper place, otherwise a half update control struct could be
     observed

   - Prevent state corruption on error rollback, which causes the state
     to advance by one and as a consequence skip it in the bringup
     sequence"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu/hotplug: Prevent state corruption on error rollback
  cpu/hotplug: Adjust misplaced smb() in cpuhp_thread_fun()

Pull random driver fix from Ted Ts'o:
 "Fix things so the choice of whether or not to trust RDRAND to
  initialize the CRNG is configurable via the boot option
  random.trust_cpu={on,off}"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
  random: make CPU trust a boot parameter

Merge tag 'kbuild-fixes-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - make setlocalversion more robust about -dirty check

 - loosen the pkg-config requirement for Kconfig

 - change missing depmod to a warning from an error

 - warn modules_install when System.map is missing

* tag 'kbuild-fixes-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: modules_install: warn when missing System.map file
  kbuild: make missing $DEPMOD a Warning instead of an Error
  kconfig: do not require pkg-config on make {menu,n}config
  kconfig: remove a spurious self-assignment
  scripts/setlocalversion: git: Make -dirty check more robust

If there is no System.map file for "make modules_install",
scripts/depmod.sh will silently exit with success, having done
nothing.  Since this is an unexpected situation, change it to
report a Warning for the missing file.  The behavior is not
changed except for the Warning message.

The (previous) silent success and new Warning can be reproduced
by:
$ make mrproper; make defconfig
$ make modules; make modules_install

and since System.map is produced by "make vmlinux", the steps
above omit producing the System.map file.
Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Pull KVM fixes from Radim Krčmář:
 "ARM:
   - Fix a VFP corruption in 32-bit guest
   - Add missing cache invalidation for CoW pages
   - Two small cleanups

  s390:
   - Fallout from the hugetlbfs support: pfmf interpretion and locking
   - VSIE: fix keywrapping for nested guests

  PPC:
   - Fix a bug where pages might not get marked dirty, causing guest
     memory corruption on migration
   - Fix a bug causing reads from guest memory to use the wrong guest
     real address for very large HPT guests (>256G of memory), leading
     to failures in instruction emulation.

  x86:
   - Fix out of bound access from malicious pv ipi hypercalls
     (introduced in rc1)
   - Fix delivery of pending interrupts when entering a nested guest,
     preventing arbitrarily late injection
   - Sanitize kvm_stat output after destroying a guest
   - Fix infinite loop when emulating a nested guest page fault and
     improve the surrounding emulation code
   - Two minor cleanups"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (28 commits)
  KVM: LAPIC: Fix pv ipis out-of-bounds access
  KVM: nVMX: Fix loss of pending IRQ/NMI before entering L2
  arm64: KVM: Remove pgd_lock
  KVM: Remove obsolete kvm_unmap_hva notifier backend
  arm64: KVM: Only force FPEXC32_EL2.EN if trapping FPSIMD
  KVM: arm/arm64: Clean dcache to PoC when changing PTE due to CoW
  KVM: s390: Properly lock mm context allow_gmap_hpage_1m setting
  KVM: s390: vsie: copy wrapping keys to right place
  KVM: s390: Fix pfmf and conditional skey emulation
  tools/kvm_stat: re-animate display of dead guests
  tools/kvm_stat: indicate dead guests as such
  tools/kvm_stat: handle guest removals more gracefully
  tools/kvm_stat: don't reset stats when setting PID filter for debugfs
  tools/kvm_stat: fix updates for dead guests
  tools/kvm_stat: fix handling of invalid paths in debugfs provider
  tools/kvm_stat: fix python3 issues
  KVM: x86: Unexport x86_emulate_instruction()
  KVM: x86: Rename emulate_instruction() to kvm_emulate_instruction()
  KVM: x86: Do not re-{try,execute} after failed emulation in L2
  KVM: x86: Default to not allowing emulation retry in kvm_mmu_page_fault
  ...

Pull ARM SoC fixes from Olof Johansson:
 "A few more fixes who have trickled in:

   - MMC bus width fixup for some Allwinner platforms

   - Fix for NULL deref in ti-aemif when no platform data is passed in

   - Fix div by 0 in SCMI code

   - Add a missing module alias in a new RPi driver"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  memory: ti-aemif: fix a potential NULL-pointer dereference
  firmware: arm_scmi: fix divide by zero when sustained_perf_level is zero
  hwmon: rpi: add module alias to raspberrypi-hwmon
  arm64: allwinner: dts: h6: fix Pine H64 MMC bus width

Merge tag 'sunxi-fixes-for-4.19' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux into fixes

Allwinner fixes for 4.19

Just one fix for H6 mmc on the Pine H64: the mmc bus width was missing
from the device tree. This was added in 4.19-rc1.

* tag 'sunxi-fixes-for-4.19' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux:
  arm64: allwinner: dts: h6: fix Pine H64 MMC bus width
Signed-off-by: Olof Johansson <olof@lixom.net>

When page-table entries are set, the compiler might optimize their
assignment by using multiple instructions to set the PTE. This might
turn into a security hazard if the user somehow manages to use the
interim PTE. L1TF does not make our lives easier, making even an interim
non-present PTE a security hazard.

Using WRITE_ONCE() to set PTEs and friends should prevent this potential
security hazard.

I skimmed the differences in the binary with and without this patch. The
differences are (obviously) greater when CONFIG_PARAVIRT=n as more
code optimizations are possible. For better and worse, the impact on the
binary with this patch is pretty small. Skimming the code did not cause
anything to jump out as a security hazard, but it seems that at least
move_soft_dirty_pte() caused set_pte_at() to use multiple writes.
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180902181451.80520-1-namit@vmware.com

activate_managed() returns EINVAL instead of -EINVAL in case of
error. While this is unlikely to happen, the positive return value would
cause further malfunction at the call site.

Fixes: 2db1f959 ("x86/vector: Handle managed interrupts proper")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org

Pull i2c fixes from Wolfram Sang:

 - bugfixes for uniphier, i801, and xiic drivers

 - ID removal (never produced) for imx

 - one MAINTAINER addition

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: xiic: Record xilinx i2c with Zynq fragment
  i2c: xiic: Make the start and the byte count write atomic
  i2c: i801: fix DNV's SMBCTRL register offset
  i2c: imx-lpi2c: Remove mx8dv compatible entry
  dt-bindings: imx-lpi2c: Remove mx8dv compatible entry
  i2c: uniphier-f: issue STOP only for last message or I2C_M_STOP
  i2c: uniphier: issue STOP only for last message or I2C_M_STOP

Pull ARC updates from Vineet Gupta:

 - Fix for atomic_fetch_#op  [Will Deacon]

 - Enable per device IOC [Eugeniy Paltsev]

 - Remove redundant gcc version checks [Masahiro Yamada]

 - Miscll platform config/DT updates [Alexey Brodkin]

* tag 'arc-4.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: don't check for HIGHMEM pages in arch_dma_alloc
  ARC: IOC: panic if both IOC and ZONE_HIGHMEM enabled
  ARC: dma [IOC] Enable per device io coherency
  ARC: dma [IOC]: mark DMA devices connected as dma-coherent
  ARC: atomics: unbork atomic_fetch_##op()
  arc: remove redundant GCC version checks
  ARC: sort Kconfig
  ARC: cleanup show_faulting_vma()
  ARC: [plat-axs*]: Enable SWAP
  ARC: [plat-axs*/plat-hsdk]: Allow U-Boot to pass MAC-address to the kernel
  ARC: configs: cleanup

Fix the cell specification mechanism to allow cells to be pre-created
without having to specify at least one address (the addresses will be
upcalled for).

This allows the cell information preload service to avoid the need to issue
loads of DNS lookups during boot to get the addresses for each cell (500+
lookups for the 'standard' cell list[*]).  The lookups can be done later as
each cell is accessed through the filesystem.

Also remove the print statement that prints a line every time a new cell is
added.

[*] There are 144 cells in the list.  Each cell is first looked up for an
    SRV record, and if that fails, for an AFSDB record.  These get a list
    of server names, each of which then has to be looked up to get the
    addresses for that server.  E.g.:

	dig srv _afs3-vlserver._udp.grand.central.org
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull MD fixes from Shaohua Li:

 - Fix a locking issue for md-cluster (Guoqing)

 - Fix a sync crash for raid10 (Ni)

 - Fix a reshape bug with raid5 cache enabled (me)

* tag 'md/4.19-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  md-cluster: release RESYNC lock after the last resync message
  RAID10 BUG_ON in raise_barrier when force is true and conf->barrier is 0
  md/raid5-cache: disable reshape completely

Pull ceph fixes from Ilya Dryomov:
 "Two rbd patches to complete support for images within namespaces that
  went into -rc1 and a use-after-free fix.

  The rbd changes have been sitting in a branch for quite a while but
  couldn't be included into the -rc1 pull request because of a pending
  wire protocol backwards compatibility fixup that only got committed
  early this week"

* tag 'ceph-for-4.19-rc3' of https://github.com/ceph/ceph-client:
  rbd: support cloning across namespaces
  rbd: factor out get_parent_info()
  ceph: avoid a use-after-free in ceph_destroy_options()

Pull fsnotify fix from Jan Kara:
 "A small fsnotify fix from Amir"

* tag 'for_v4.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fsnotify: fix ignore mask logic in fsnotify()

Pull arm64 fix from Will Deacon:
 "Just one small fix here, preventing a VM_WARN_ON when a !present
  PMD/PUD is "freed" as part of a huge ioremap() operation.

  The correct behaviour is to skip the free silently in this case, which
  is a little weird (the function is a bit of a misnomer), but it
  follows the x86 implementation"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: fix erroneous warnings in page freeing functions

Pull ACPI fixes from Rafael Wysocki:
 "These fix a regression from the 4.18 cycle in the ACPI driver for
  Intel SoCs (LPSS) and prevent dmi_check_system() from being called on
  non-x86 systems in the ACPI core.

  Specifics:

   - Fix a power management regression in the ACPI driver for Intel SoCs
     (LPSS) introduced by a system-wide suspend/resume fix during the
     4.18 cycle (Zhang Rui).

   - Prevent dmi_check_system() from being called on non-x86 systems in
     the ACPI core (Jean Delvare)"

* tag 'acpi-4.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / LPSS: Force LPSS quirks on boot
  ACPI / bus: Only call dmi_check_system() on X86

Pull sound fixes from Takashi Iwai:
 "Just a few small fixes:

   - a fix for the recursive work cancellation in a specific HD-audio
     operation mode

   - a fix for potentially uninitialized memory access via rawmidi

   - the register bit access fixes for ASoC HD-audio"

* tag 'sound-4.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda: Fix several mismatch for register mask and value
  ALSA: rawmidi: Initialize allocated buffers
  ALSA: hda - Fix cancel_work_sync() stall from jackpoll work

Dan Carpenter reported that the untrusted data returns from kvm_register_read()
results in the following static checker warning:
  arch/x86/kvm/lapic.c:576 kvm_pv_send_ipi()
  error: buffer underflow 'map->phys_map' 's32min-s32max'

KVM guest can easily trigger this by executing the following assembly sequence
in Ring0:

mov $10, %rax
mov $0xFFFFFFFF, %rbx
mov $0xFFFFFFFF, %rdx
mov $0, %rsi
vmcall

As this will cause KVM to execute the following code-path:
vmx_handle_exit() -> handle_vmcall() -> kvm_emulate_hypercall() -> kvm_pv_send_ipi()
which will reach out-of-bounds access.

This patch fixes it by adding a check to kvm_pv_send_ipi() against map->max_apic_id,
ignoring destinations that are not present and delivering the rest. We also check
whether or not map->phys_map[min + i] is NULL since the max_apic_id is set to the
max apic id, some phys_map maybe NULL when apic id is sparse, especially kvm
unconditionally set max_apic_id to 255 to reserve enough space for any xAPIC ID.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Liran Alon <liran.alon@oracle.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
[Add second "if (min > map->max_apic_id)" to complete the fix. -Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

Consider the case L1 had a IRQ/NMI event until it executed
VMLAUNCH/VMRESUME which wasn't delivered because it was disallowed
(e.g. interrupts disabled). When L1 executes VMLAUNCH/VMRESUME,
L0 needs to evaluate if this pending event should cause an exit from
L2 to L1 or delivered directly to L2 (e.g. In case L1 don't intercept
EXTERNAL_INTERRUPT).

Usually this would be handled by L0 requesting a IRQ/NMI window
by setting VMCS accordingly. However, this setting was done on
VMCS01 and now VMCS02 is active instead. Thus, when L1 executes
VMLAUNCH/VMRESUME we force L0 to perform pending event evaluation by
requesting a KVM_REQ_EVENT.

Note that above scenario exists when L1 KVM is about to enter L2 but
requests an "immediate-exit". As in this case, L1 will
disable-interrupts and then send a self-IPI before entering L2.
Reviewed-by: Nikita Leshchenko <nikita.leshchenko@oracle.com>
Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

Merge tag 'kvm-arm-fixes-for-v4.19-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm

Fixes for KVM/ARM for Linux v4.19 v2:

 - Fix a VFP corruption in 32-bit guest
 - Add missing cache invalidation for CoW pages
 - Two small cleanups

KVM: s390: Fixes for 4.19

- Fallout from the hugetlbfs support: pfmf interpretion and locking
- VSIE: fix keywrapping for nested guests

The lock has never been used and the page tables are protected by
mmu_lock in struct kvm.
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>

kvm_unmap_hva is long gone, and we only have kvm_unmap_hva_range to
deal with. Drop the now obsolete code.

Fixes: fb1522e0 ("KVM: update to new mmu_notifier semantic v2")
Cc: James Hogan <jhogan@kernel.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>

If trapping FPSIMD in the context of an AArch32 guest, it is critical
to set FPEXC32_EL2.EN to 1 so that the trapping is taken to EL2 and
not EL1.

Conversely, it is just as critical *not* to set FPEXC32_EL2.EN to 1
if we're not going to trap FPSIMD, as we then corrupt the existing
VFP state.

Moving the call to __activate_traps_fpsimd32 to the point where we
know for sure that we are going to trap ensures that we don't set that
bit spuriously.

Fixes: e6b673b7 ("KVM: arm64: Optimise FPSIMD handling to reduce guest/host thrashing")
Cc: stable@vger.kernel.org # v4.18
Cc: Dave Martin <dave.martin@arm.com>
Reported-by: Alexander Graf <agraf@suse.de>
Tested-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>

When triggering a CoW, we unmap the RO page via an MMU notifier
(invalidate_range_start), and then populate the new PTE using another
one (change_pte). In the meantime, we'll have copied the old page
into the new one.

The problem is that the data for the new page is sitting in the
cache, and should the guest have an uncached mapping to that page
(or its MMU off), following accesses will bypass the cache.

In a way, this is similar to what happens on a translation fault:
We need to clean the page to the PoC before mapping it. So let's just
do that.

This fixes a KVM unit test regression observed on a HiSilicon platform,
and subsequently reproduced on Seattle.

Fixes: a9c0e12e ("KVM: arm/arm64: Only clean the dcache on translation fault")
Cc: stable@vger.kernel.org # v4.16+
Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>

Include xilinx soft i2c controller to Zynq fragment to make clear who is
responsible for it.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Merge ACPI core fix to avoid calling dmi_check_system() on non-x86.

* acpi-bus:
  ACPI / bus: Only call dmi_check_system() on X86