The driver needs help determining whether it is dealing with a touchscreen
or a touchpad, and with button mapping. Previously we supported passing
this data via device properties, and also had DMI lists for Chromebooks
that specified Atmel devices in ACPI, but did not provide enough data
there. Now that chromeos_laptop driver is adjusted to supply necessary
device properties even for ACPI devices, we can drop the DMI tables and
refuse to probe if device properties are not attached to the device.

We use presence of "compatible" property to determine if device properties
are attached to the device or not and rely on chromeos_laptop to re-probe
the device after attaching missing device properties to it.
Reviewed-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Merge branch 'ib-chrome-platform-atmel-mxt-ts-device-properties' of git://git.kernel.org/pub/scm/linux/kernel/git/bleung/chrome-platform into next

Sync up with chrome-platform again to bring in device properties for
Atmel touch controllers incompletely described in ACPI.

Sync up with mainline to bring in Atmel controller changes for Caroline.

This seems to be Synaptics specific, as some Elan touchpads are not
correctly switching to SMBus if we call deactivate before switching to
SMBus on cold boot and on resume.

Tested with the T480s
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: KT Liao <kt.liao@emc.com.tw>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

New ICs are using a different scheme for the alternate bus parameter.
Given that they are new and are only using either PS2 only or PS2 + SMBus
Host Notify, we force those new ICs to use the SMBus solution for enhanced
reporting.

This allows the touchpad found on the Lenovo T480s to report 5 fingers
every 8 ms, instead of having a limit of 2 every 8 ms.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: KT Liao <kt.liao@emc.com.tw>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Many of the Elantech devices are connected through PS/2 and a different
bus (SMBus or plain I2C).

To not break any existing device, we only enable SMBus based
on a module parameter. If some laptops require the quirk to
be set, we will have to rely on a list of PNPIds or MDI matching
to individually expose those hardware over SMBus.
the parameter mentioned above is elantech_smbus from the psmouse
module.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: KT Liao <kt.liao@emc.com.tw>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

The command ETP_RESOLUTION_QUERY also contains the bus information.
It is better to fetch it once, while we are querying for device
information.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: KT Liao <kt.liao@emc.com.tw>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

In preparation for SMBus device support, move static device
information that we query form the touchpad upon initialization into
separate structure. This will allow us to query the device without
allocating memory first.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: KT Liao <kt.liao@emc.com.tw>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

The Elan touchpads over I2C/SMBus also can handle a trackstick.
Unfortunately, nothing tells us if the device supports trackstick (the
information lies in the PS/2 node), so rely on device properties to
determine whether to enable the trackstick node.

Link: https://bugzilla.redhat.com/show_bug.cgi?id=1313939Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: KT Liao <kt.liao@emc.com.tw>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

BayTrail-based and newer Chromebooks describe their peripherals in ACPI;
unfortunately their description is not complete, and peripherals
drivers, such as driver for Atmel Touch controllers, has to resort to
DMI-matching to configure the peripherals properly. To avoid polluting
peripheral driver code, let's teach chromeos_laptop driver to supply
missing data via generic device properties.

Note we supply "compatible" string for Atmel peripherals not because it is
needed for matching devices and driver (matching is still done on ACPI HID
entries), but because peripherals driver will be using presence of
"compatible" property to determine if device properties have been attached
to the device, and fail to bind if they are absent.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Benson Leung <bleung@chromium.org>

Pull parisc fixlets from Helge Deller:
 "Three small section mismatch fixes, one of them was found by 0-day
  test infrastructure"

* 'parisc-4.17-5' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Move ccio_cujo20_fixup() into init section
  parisc: Move setup_profiling_timer() out of init section
  parisc: Move find_pa_parent_type() out of init section

Pull btrfs fixes from David Sterba:
 "We've accumulated some fixes during the last week, some of them were
  in the works for a longer time but there are some newer ones too.

  Most of the fixes have a reproducer and fix user visible problems,
  also candidates for stable kernels. They IMHO qualify for a late rc,
  though I did not expect that many"

* tag 'for-4.17-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix crash when trying to resume balance without the resume flag
  btrfs: Fix delalloc inodes invalidation during transaction abort
  btrfs: Split btrfs_del_delalloc_inode into 2 functions
  btrfs: fix reading stale metadata blocks after degraded raid1 mounts
  btrfs: property: Set incompat flag if lzo/zstd compression is set
  Btrfs: fix duplicate extents after fsync of file with prealloc extents
  Btrfs: fix xattr loss after power failure
  Btrfs: send, fix invalid access to commit roots due to concurrent snapshotting

Pull ARM fixes from Russell King:

 - Łukasz Stelmach spotted a couple of issues with the decompressor.

 - a couple of kdump fixes found while testing kdump

 - replace some perl with shell code

 - resolve SIGFPE breakage

 - kprobes fixes

* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: fix kill( ,SIGFPE) breakage
  ARM: 8772/1: kprobes: Prohibit kprobes on get_user functions
  ARM: 8771/1: kprobes: Prohibit kprobes on do_undefinstr
  ARM: 8770/1: kprobes: Prohibit probing on optimized_callback
  ARM: 8769/1: kprobes: Fix to use get_kprobe_ctlblk after irq-disabed
  ARM: replace unnecessary perl with sed and the shell $(( )) operator
  ARM: kexec: record parent context registers for non-crash CPUs
  ARM: kexec: fix kdump register saving on panic()
  ARM: 8758/1: decompressor: restore r1 and r2 just before jumping to the kernel
  ARM: 8753/1: decompressor: add a missing parameter to the addruart macro

Pull x86 fixes from Thomas Gleixner:
 "An unfortunately larger set of fixes, but a large portion is
  selftests:

   - Fix the missing clusterid initializaiton for x2apic cluster
     management which caused boot failures due to IPIs being sent to the
     wrong cluster

   - Drop TX_COMPAT when a 64bit executable is exec()'ed from a compat
     task

   - Wrap access to __supported_pte_mask in __startup_64() where clang
     compile fails due to a non PC relative access being generated.

   - Two fixes for 5 level paging fallout in the decompressor:

      - Handle GOT correctly for paging_prepare() and
        cleanup_trampoline()

      - Fix the page table handling in cleanup_trampoline() to avoid
        page table corruption.

   - Stop special casing protection key 0 as this is inconsistent with
     the manpage and also inconsistent with the allocation map handling.

   - Override the protection key wen moving away from PROT_EXEC to
     prevent inaccessible memory.

   - Fix and update the protection key selftests to address breakage and
     to cover the above issue

   - Add a MOV SS self test"

[ Part of the x86 fixes were in the earlier core pull due to dependencies ]

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  x86/mm: Drop TS_COMPAT on 64-bit exec() syscall
  x86/apic/x2apic: Initialize cluster ID properly
  x86/boot/compressed/64: Fix moving page table out of trampoline memory
  x86/boot/compressed/64: Set up GOT for paging_prepare() and cleanup_trampoline()
  x86/pkeys: Do not special case protection key 0
  x86/pkeys/selftests: Add a test for pkey 0
  x86/pkeys/selftests: Save off 'prot' for allocations
  x86/pkeys/selftests: Fix pointer math
  x86/pkeys: Override pkey when moving away from PROT_EXEC
  x86/pkeys/selftests: Fix pkey exhaustion test off-by-one
  x86/pkeys/selftests: Add PROT_EXEC test
  x86/pkeys/selftests: Factor out "instruction page"
  x86/pkeys/selftests: Allow faults on unknown keys
  x86/pkeys/selftests: Avoid printf-in-signal deadlocks
  x86/pkeys/selftests: Remove dead debugging code, fix dprint_in_signal
  x86/pkeys/selftests: Stop using assert()
  x86/pkeys/selftests: Give better unexpected fault error messages
  x86/selftests: Add mov_to_ss test
  x86/mpx/selftests: Adjust the self-test to fresh distros that export the MPX ABI
  x86/pkeys/selftests: Adjust the self-test to fresh distros that export the pkeys ABI
  ...

Pull UP timer fix from Thomas Gleixner:
 "Work around the for_each_cpu() oddity on UP kernels in the tick
  broadcast code which causes boot failures because the CPU0 bit is
  always reported as set independent of the cpumask content"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tick/broadcast: Use for_each_cpu() specially on UP kernels

Pull scheduler fixlets from Thomas Gleixner:
 "Three trivial fixlets for the scheduler:

   - move print_rt_rq() and print_dl_rq() declarations to the right
     place

   - make grub_reclaim() static

   - fix the bogus documentation reference in Kconfig"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Fix documentation file path
  sched/deadline: Make the grub_reclaim() function static
  sched/debug: Move the print_rt_rq() and print_dl_rq() declarations to kernel/sched/sched.h

Pull RAS fix from Thomas Gleixner:
 "Fix a regression in the new AMD SMCA code which issues an SMP function
  call from the early interrupt disabled region of CPU hotplug. To avoid
  that, use cached block addresses which can be used directly"

* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/MCE/AMD: Cache SMCA MISC block addresses

Pull perf tooling fixes from Thomas Gleixner:

 - fix segfault when processing unknown threads in cs-etm

 - fix "perf test inet_pton" on s390 failing due to missing inline

 - display all available events on 'perf annotate --stdio'

 - add missing newline when parsing an empty BPF program

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf tools: Add missing newline when parsing empty BPF proggie
  perf cs-etm: Remove redundant space
  perf cs-etm: Support unknown_thread in cs_etm_auxtrace
  perf annotate: Display all available events on --stdio
  perf test: "probe libc's inet_pton" fails on s390 due to missing inline

Pull locking fixes from Thomas Gleixner:
 "Two fixes to address shortcomings of the rwsem/percpu-rwsem lock
  debugging code which emits false positive warnings when the rwsem is
  anonymously locked and unlocked"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/percpu-rwsem: Annotate rwsem ownership transfer by setting RWSEM_OWNER_UNKNOWN
  locking/rwsem: Add a new RWSEM_ANONYMOUSLY_OWNED flag

Pull EFI fixes from Thomas Gleixner:

 - Use explicitely sized type for the romimage pointer in the 32bit EFI
   protocol struct so a 64bit kernel does not expand it to 64bit. Ditto
   for the 64bit struct to avoid the reverse issue on 32bit kernels.

 - Handle randomized tex offset correctly in the ARM64 EFI stub to avoid
   unaligned data resulting in stack corruption and other hard to
   diagnose wreckage.

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/libstub/arm64: Handle randomized TEXT_OFFSET
  efi: Avoid potential crashes, fix the 'struct efi_pci_io_protocol_32' definition for mixed mode

Pull core fixes from Thomas Gleixner:

 - Unbreak the BPF compilation which got broken by the unconditional
   requirement of asm-goto, which is not supported by clang.

 - Prevent probing on exception masking instructions in uprobes and
   kprobes to avoid the issues of the delayed exceptions instead of
   having an ugly workaround.

 - Prevent a double free_page() in the error path of do_kexec_load()

 - A set of objtool updates addressing various issues mostly related to
   switch tables and the noreturn detection for recursive sibling calls

 - Header sync for tools.

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Detect RIP-relative switch table references, part 2
  objtool: Detect RIP-relative switch table references
  objtool: Support GCC 8 switch tables
  objtool: Support GCC 8's cold subfunctions
  objtool: Fix "noreturn" detection for recursive sibling calls
  objtool, kprobes/x86: Sync the latest <asm/insn.h> header with tools/objtool/arch/x86/include/asm/insn.h
  x86/cpufeature: Guard asm_volatile_goto usage for BPF compilation
  uprobes/x86: Prohibit probing on MOV SS instruction
  kprobes/x86: Prohibit probing on exception masking instructions
  x86/kexec: Avoid double free_page() upon do_kexec_load() failure

Pull ARM SoC fixes from Olof Johansson:
 "A handful of fixes. I've been queuing them up a bit too long so the
  list is longer than it otherwise would have been spread out across a
  few -rcs.

  In general, it's a scattering of fixes across several platforms,
  nothing truly serious enough to point out.

  There's a slightly larger batch of them for the Davinci platforms due
  to work to bring them back to life after some time, so there's a
  handful of regressions, some of them going back very far, others more
  recent.

  There's also a few patches fixing DT on Renesas platforms since they
  changed some bindings without remaining backwards compatible,
  splitting up describing LVDS as a proper bridge instead of having it
  as part of the display unit.

  We could push for them to be backwards compatible with old device
  trees, but it's likely to regress eventually if nobody's actually
  using said compatibility"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (36 commits)
  ARM: davinci: board-dm646x-evm: set VPIF capture card name
  ARM: davinci: board-dm646x-evm: pass correct I2C adapter id for VPIF
  ARM: davinci: dm646x: fix timer interrupt generation
  ARM: keystone: fix platform_domain_notifier array overrun
  arm64: dts: exynos: Fix interrupt type for I2S1 device on Exynos5433
  ARM: dts: imx51-zii-rdu1: fix touchscreen bindings
  firmware: arm_scmi: Use after free in scmi_create_protocol_device()
  ARM: dts: cygnus: fix irq type for arm global timer
  Revert "ARM: dts: logicpd-som-lv: Fix pinmux controller references"
  tee: check shm references are consistent in offset/size
  tee: shm: fix use-after-free via temporarily dropped reference
  ARM: dts: imx7s: Pass the 'fsl,sec-era' property
  ARM: dts: tegra20: Revert "Fix ULPI regression on Tegra20"
  ARM: dts: correct missing "compatible" entry for ti81xx SoCs
  ARM: OMAP1: ams-delta: fix deferred_fiq handler
  arm64: tegra: Make BCM89610 PHY interrupt as active low
  ARM: davinci: fix GPIO lookup for I2C
  ARM: dts: logicpd-som-lv: Fix pinmux controller references
  ARM: dts: logicpd-som-lv: Fix Audio Mute
  ARM: dts: logicpd-som-lv: Fix WL127x Startup Issues
  ...

Merge tag 'tegra-for-4.17-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux into fixes

arm64: tegra: Device tree fixes for v4.17

This contains a one-line update to the device tree of the Tegra186 P3310
processor module, fixing the polarity of the PHY interrupt. Originally,
this was queued to go into v4.18, but the PHY ID matching patch has now
found its way into v4.17-rc5, which means that the PHY driver will know
how to identify the PHY on this board and try to use the interrupt. This
will unfortunately cause networking to break on P3310, hence why I think
this should go into v4.17.

* tag 'tegra-for-4.17-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux:
  arm64: tegra: Make BCM89610 PHY interrupt as active low
Signed-off-by: Olof Johansson <olof@lixom.net>

Commit 7771c664 ("signal/arm: Document conflicts with SI_USER and
SIGFPE") broke the siginfo structure for userspace triggered signals,
causing the strace testsuite to regress.  Fix this by eliminating
the FPE_FIXME definition (which is at the root of the breakage) and
use FPE_FLTINV instead for the case where the hardware appears to be
reporting nonsense.

Fixes: 7771c664 ("signal/arm: Document conflicts with SI_USER and SIGFPE")
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

Pull dmaengine fix from Vinod Koul:

 - qcom bam runtime_pm fix

 - email update for Vinod

* tag 'dmaengine-fix-4.17-rc6' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: qcom: bam_dma: check if the runtime pm enabled
  dmaengine: Update email address for Vinod

Commit be83bbf8 ("mmap: introduce sane default mmap limits") was
introduced to catch problems in various ad-hoc character device drivers
doing mmap and getting the size limits wrong.  In the process, it used
"known good" limits for the normal cases of mapping regular files and
block device drivers.

It turns out that the "s_maxbytes" limit was less "known good" than I
thought.  In particular, /proc doesn't set it, but exposes one regular
file to mmap: /proc/vmcore.  As a result, that file got limited to the
default MAX_INT s_maxbytes value.

This went unnoticed for a while, because apparently the only thing that
needs it is the s390 kernel zfcpdump, but there might be other tools
that use this too.

Vasily suggested just changing s_maxbytes for all of /proc, which isn't
wrong, but makes me nervous at this stage.  So instead, just make the
new mmap limit always be MAX_LFS_FILESIZE for regular files, which won't
affect anything else.  It wasn't the regular file case I was worried
about.

I'd really prefer for maxsize to have been per-inode, but that is not
how things are today.

Fixes: be83bbf8 ("mmap: introduce sane default mmap limits")
Reported-by: Vasily Gorbik <gor@linux.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

... into a global, two-dimensional array and service subsequent reads from
that cache to avoid rdmsr_on_cpu() calls during CPU hotplug (IPIs with IRQs
disabled).

In addition, this fixes a KASAN slab-out-of-bounds read due to wrong usage
of the bank->blocks pointer.

Fixes: 27bd5950 ("x86/mce/AMD: Get address from already initialized block")
Reported-by: Johannes Hirte <johannes.hirte@datenkhaos.de>
Tested-by: Johannes Hirte <johannes.hirte@datenkhaos.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Yazen Ghannam <yazen.ghannam@amd.com>
Link: http://lkml.kernel.org/r/20180414004230.GA2033@probook

Since do_undefinstr() uses get_user to get the undefined
instruction, it can be called before kprobes processes
recursive check. This can cause an infinit recursive
exception.
Prohibit probing on get_user functions.

Fixes: 24ba613c ("ARM kprobes: core code")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

Prohibit kprobes on do_undefinstr because kprobes on
arm is implemented by undefined instruction. This means
if we probe do_undefinstr(), it can cause infinit
recursive exception.

Fixes: 24ba613c ("ARM kprobes: core code")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

Prohibit probing on optimized_callback() because
it is called from kprobes itself. If we put a kprobes
on it, that will cause a recursive call loop.
Mark it NOKPROBE_SYMBOL.

Fixes: 0dc016db ("ARM: kprobes: enable OPTPROBES for ARM 32")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

Since get_kprobe_ctlblk() uses smp_processor_id() to access
per-cpu variable, it hits smp_processor_id sanity check as below.

[    7.006928] BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
[    7.007859] caller is debug_smp_processor_id+0x20/0x24
[    7.008438] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.16.0-rc1-00192-g4eb17253e4b5 #1
[    7.008890] Hardware name: Generic DT based system
[    7.009917] [<c0313f0c>] (unwind_backtrace) from [<c030e6d8>] (show_stack+0x20/0x24)
[    7.010473] [<c030e6d8>] (show_stack) from [<c0c64694>] (dump_stack+0x84/0x98)
[    7.010990] [<c0c64694>] (dump_stack) from [<c071ca5c>] (check_preemption_disabled+0x138/0x13c)
[    7.011592] [<c071ca5c>] (check_preemption_disabled) from [<c071ca80>] (debug_smp_processor_id+0x20/0x24)
[    7.012214] [<c071ca80>] (debug_smp_processor_id) from [<c03335e0>] (optimized_callback+0x2c/0xe4)
[    7.013077] [<c03335e0>] (optimized_callback) from [<bf0021b0>] (0xbf0021b0)

To fix this issue, call get_kprobe_ctlblk() right after
irq-disabled since that disables preemption.

Fixes: 0dc016db ("ARM: kprobes: enable OPTPROBES for ARM 32")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

You can build a kernel in a cross compiling environment that doesn't
have perl in the $PATH. Commit 429f7a06 broke that for 32 bit
ARM. Fix it.

As reported by Stephen Rothwell, it appears that the symbols can be
either part of the BSS section or absolute symbols depending on the
binutils version.  When they're an absolute symbol, the $(( ))
operator errors out and the build fails.  Fix this as well.

Fixes: 429f7a06 ("ARM: decompressor: fix BSS size calculation")
Reported-by: Rob Landley <rob@landley.net>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

How we got to machine_crash_nonpanic_core() (iow, from an IPI, etc) is
not interesting for debugging a crash.  The more interesting context
is the parent context prior to the IPI being received.

Record the parent context register state rather than the register state
in machine_crash_nonpanic_core(), which is more relevant to the failing
condition.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

When a panic() occurs, the kexec code uses smp_send_stop() to stop
the other CPUs, but this results in the CPU register state not being
saved, and gdb is unable to inspect the state of other CPUs.

Commit 0ee59413 ("x86/panic: replace smp_send_stop() with kdump
friendly version in panic path") addressed the issue on x86, but
ignored other architectures.  Address the issue on ARM by splitting
out the crash stop implementation to crash_smp_send_stop() and
adding the necessary protection.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

The hypervisor setup before __enter_kernel destroys the value
sotred in r1. The value needs to be restored just before the jump.

Fixes: 6b52f7bd ("ARM: hyp-stub: Use r1 for the soft-restart address")
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

In commit 639da5ee ("ARM: add an extra temp register to the low
level debugging addruart macro") an additional temporary register was
added to the addruart macro, but the decompressor code wasn't updated.

Fixes: 639da5ee ("ARM: add an extra temp register to the low level debugging addruart macro")
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

The x86 mmap() code selects the mmap base for an allocation depending on
the bitness of the syscall. For 64bit sycalls it select mm->mmap_base and
for 32bit mm->mmap_compat_base.

exec() calls mmap() which in turn uses in_compat_syscall() to check whether
the mapping is for a 32bit or a 64bit task. The decision is made on the
following criteria:

  ia32    child->thread.status & TS_COMPAT
   x32    child->pt_regs.orig_ax & __X32_SYSCALL_BIT
  ia64    !ia32 && !x32

__set_personality_x32() was dropping TS_COMPAT flag, but
set_personality_64bit() has kept compat syscall flag making
in_compat_syscall() return true during the first exec() syscall.

Which in result has user-visible effects, mentioned by Alexey:
1) It breaks ASAN
$ gcc -fsanitize=address wrap.c -o wrap-asan
$ ./wrap32 ./wrap-asan true
==1217==Shadow memory range interleaves with an existing memory mapping. ASan cannot proceed correctly. ABORTING.
==1217==ASan shadow was supposed to be located in the [0x00007fff7000-0x10007fff7fff] range.
==1217==Process memory map follows:
        0x000000400000-0x000000401000   /home/izbyshev/test/gcc/asan-exec-from-32bit/wrap-asan
        0x000000600000-0x000000601000   /home/izbyshev/test/gcc/asan-exec-from-32bit/wrap-asan
        0x000000601000-0x000000602000   /home/izbyshev/test/gcc/asan-exec-from-32bit/wrap-asan
        0x0000f7dbd000-0x0000f7de2000   /lib64/ld-2.27.so
        0x0000f7fe2000-0x0000f7fe3000   /lib64/ld-2.27.so
        0x0000f7fe3000-0x0000f7fe4000   /lib64/ld-2.27.so
        0x0000f7fe4000-0x0000f7fe5000
        0x7fed9abff000-0x7fed9af54000
        0x7fed9af54000-0x7fed9af6b000   /lib64/libgcc_s.so.1
[snip]

2) It doesn't seem to be great for security if an attacker always knows
that ld.so is going to be mapped into the first 4GB in this case
(the same thing happens for PIEs as well).

The testcase:
$ cat wrap.c

int main(int argc, char *argv[]) {
  execvp(argv[1], &argv[1]);
  return 127;
}

$ gcc wrap.c -o wrap
$ LD_SHOW_AUXV=1 ./wrap ./wrap true |& grep AT_BASE
AT_BASE:         0x7f63b8309000
AT_BASE:         0x7faec143c000
AT_BASE:         0x7fbdb25fa000

$ gcc -m32 wrap.c -o wrap32
$ LD_SHOW_AUXV=1 ./wrap32 ./wrap true |& grep AT_BASE
AT_BASE:         0xf7eff000
AT_BASE:         0xf7cee000
AT_BASE:         0x7f8b9774e000

Fixes: 1b028f78 ("x86/mm: Introduce mmap_compat_base() for 32-bit mmap()")
Fixes: ada26481 ("x86/mm: Make in_compat_syscall() work during exec")
Reported-by: Alexey Izbyshev <izbyshev@ispras.ru>
Bisected-by: Alexander Monakov <amonakov@ispras.ru>
Investigated-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Alexander Monakov <amonakov@ispras.ru>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: stable@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Link: https://lkml.kernel.org/r/20180517233510.24996-1-dima@arista.com

With the following commit:

  fd35c88b ("objtool: Support GCC 8 switch tables")

I added a "can't find switch jump table" warning, to stop covering up
silent failures if add_switch_table() can't find anything.

That warning found yet another bug in the objtool switch table detection
logic.  For cases 1 and 2 (as described in the comments of
find_switch_table()), the find_symbol_containing() check doesn't adjust
the offset for RIP-relative switch jumps.

Incidentally, this bug was already fixed for case 3 with:

  6f5ec299 ("objtool: Detect RIP-relative switch table references")

However, that commit missed the fix for cases 1 and 2.

The different cases are now starting to look more and more alike.  So
fix the bug by consolidating them into a single case, by checking the
original dynamic jump instruction in the case 3 loop.

This also simplifies the code and makes it more robust against future
switch table detection issues -- of which I'm sure there will be many...

Switch table detection has been the most fragile area of objtool, by
far.  I long for the day when we'll have a GCC plugin for annotating
switch tables.  Linus asked me to delay such a plugin due to the
flakiness of the plugin infrastructure in older versions of GCC, so this
rickety code is what we're stuck with for now.  At least the code is now
a little simpler than it was.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/f400541613d45689086329432f3095119ffbc328.1526674218.git.jpoimboe@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

When CONFIG_RANDOMIZE_TEXT_OFFSET=y, TEXT_OFFSET is an arbitrary
multiple of PAGE_SIZE in the interval [0, 2MB).

The EFI stub does not account for the potential misalignment of
TEXT_OFFSET relative to EFI_KIMG_ALIGN, and produces a randomized
physical offset which is always a round multiple of EFI_KIMG_ALIGN.
This may result in statically allocated objects whose alignment exceeds
PAGE_SIZE to appear misaligned in memory. This has been observed to
result in spurious stack overflow reports and failure to make use of
the IRQ stacks, and theoretically could result in a number of other
issues.

We can OR in the low bits of TEXT_OFFSET to ensure that we have the
necessary offset (and hence preserve the misalignment of TEXT_OFFSET
relative to EFI_KIMG_ALIGN), so let's do that.
Reported-by: Kim Phillips <kim.phillips@arm.com>
Tested-by: Kim Phillips <kim.phillips@arm.com>
[ardb: clarify comment and commit log, drop unneeded parens]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Fixes: 6f26b367 ("arm64: kaslr: increase randomization granularity")
Link: http://lkml.kernel.org/r/20180518140841.9731-2-ard.biesheuvel@linaro.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>