The KSTK_ESP macro is used to determine the user stack pointer for a
given task. In particular, this is used to to report the '[stack]' VMA
in /proc/self/maps, which is used by Android to determine the stack
location for children of the main thread.

This patch fixes the macro to use user_stack_pointer instead of directly
returning sp. This means that we report w13 instead of sp, since the
former is used as the stack pointer when executing in AArch32 state.

Cc: <stable@vger.kernel.org>
Reported-by: Serban Constantinescu <Serban.Constantinescu@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

Commit 5f888a1d33 (ARM64: perf: support dwarf unwinding in compat mode)
changes user_stack_pointer() to return the compat SP for 32-bit tasks
but without brackets around the whole definition, with possible issues
on the call sites (noticed with a subsequent fix for KSTK_ESP).

Fixes: 5f888a1d33c4 (ARM64: perf: support dwarf unwinding in compat mode)
Reported-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

I'm not sure what I was on when I wrote this, but when iterating over
the hardware watchpoint array (hbp_watch_array), our index is off by
ARM_MAX_BRP, so we walk off the end of our thread_struct...

... except, a dodgy condition in the loop means that it never executes
at all (bp cannot be NULL).

This patch fixes the code so that we remove the bp check and use the
correct index for accessing the watchpoint structures.

Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

Now that we support 48-bit physical addressing, update MAX_PHYSMEM_BITS
accordingly.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@caviumnetworks.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

arch/arm/ just grew support for the new memfd_create and getrandom
syscalls, so add them to our compat layer too.

Signed-off-by: Will Deacon <will.deacon@arm.com>

Pull arch signal handling cleanup from Richard Weinberger:
 "This patch series moves all remaining archs to the get_signal(),
  signal_setup_done() and sigsp() functions.

  Currently these archs use open coded variants of the said functions.
  Further, unused parameters get removed from get_signal_to_deliver(),
  tracehook_signal_handler() and signal_delivered().

  At the end of the day we save around 500 lines of code."

* 'signal-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc: (43 commits)
  powerpc: Use sigsp()
  openrisc: Use sigsp()
  mn10300: Use sigsp()
  mips: Use sigsp()
  microblaze: Use sigsp()
  metag: Use sigsp()
  m68k: Use sigsp()
  m32r: Use sigsp()
  hexagon: Use sigsp()
  frv: Use sigsp()
  cris: Use sigsp()
  c6x: Use sigsp()
  blackfin: Use sigsp()
  avr32: Use sigsp()
  arm64: Use sigsp()
  arc: Use sigsp()
  sas_ss_flags: Remove nested ternary if
  Rip out get_signal_to_deliver()
  Clean up signal_delivered()
  tracehook_signal_handler: Remove sig, info, ka and regs
  ...

Merge more incoming from Andrew Morton:
 "Two new syscalls:

     memfd_create in "shm: add memfd_create() syscall"
     kexec_file_load in "kexec: implementation of new syscall kexec_file_load"

  And:

   - Most (all?) of the rest of MM

   - Lots of the usual misc bits

   - fs/autofs4

   - drivers/rtc

   - fs/nilfs

   - procfs

   - fork.c, exec.c

   - more in lib/

   - rapidio

   - Janitorial work in filesystems: fs/ufs, fs/reiserfs, fs/adfs,
     fs/cramfs, fs/romfs, fs/qnx6.

   - initrd/initramfs work

   - "file sealing" and the memfd_create() syscall, in tmpfs

   - add pci_zalloc_consistent, use it in lots of places

   - MAINTAINERS maintenance

   - kexec feature work"

* emailed patches from Andrew Morton <akpm@linux-foundation.org: (193 commits)
  MAINTAINERS: update nomadik patterns
  MAINTAINERS: update usb/gadget patterns
  MAINTAINERS: update DMA BUFFER SHARING patterns
  kexec: verify the signature of signed PE bzImage
  kexec: support kexec/kdump on EFI systems
  kexec: support for kexec on panic using new system call
  kexec-bzImage64: support for loading bzImage using 64bit entry
  kexec: load and relocate purgatory at kernel load time
  purgatory: core purgatory functionality
  purgatory/sha256: provide implementation of sha256 in purgaotory context
  kexec: implementation of new syscall kexec_file_load
  kexec: new syscall kexec_file_load() declaration
  kexec: make kexec_segment user buffer pointer a union
  resource: provide new functions to walk through resources
  kexec: use common function for kimage_normal_alloc() and kimage_crash_alloc()
  kexec: move segment verification code in a separate function
  kexec: rename unusebale_pages to unusable_pages
  kernel: build bin2c based on config option CONFIG_BUILD_BIN2C
  bin2c: move bin2c in scripts/basic
  shm: wait for pins to be released when sealing
  ...

The core mm code will provide a default gate area based on
FIXADDR_USER_START and FIXADDR_USER_END if
!defined(__HAVE_ARCH_GATE_AREA) && defined(AT_SYSINFO_EHDR).

This default is only useful for ia64.  arm64, ppc, s390, sh, tile, 64-bit
UML, and x86_32 have their own code just to disable it.  arm, 32-bit UML,
and x86_64 have gate areas, but they have their own implementations.

This gets rid of the default and moves the code into ia64.

This should save some code on architectures without a gate area: it's now
possible to inline the gate_area functions in the default case.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [in principle]
Acked-by: Richard Weinberger <richard@nod.at> [for um]
Acked-by: Will Deacon <will.deacon@arm.com> [for arm64]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Nathan Lynch <Nathan_Lynch@mentor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull second round of KVM changes from Paolo Bonzini:
 "Here are the PPC and ARM changes for KVM, which I separated because
  they had small conflicts (respectively within KVM documentation, and
  with 3.16-rc changes).  Since they were all within the subsystem, I
  took care of them.

  Stephen Rothwell reported some snags in PPC builds, but they are all
  fixed now; the latest linux-next report was clean.

  New features for ARM include:
   - KVM VGIC v2 emulation on GICv3 hardware
   - Big-Endian support for arm/arm64 (guest and host)
   - Debug Architecture support for arm64 (arm32 is on Christoffer's todo list)

  And for PPC:
   - Book3S: Good number of LE host fixes, enable HV on LE
   - Book3S HV: Add in-guest debug support

  This release drops support for KVM on the PPC440.  As a result, the
  PPC merge removes more lines than it adds.  :)

  I also included an x86 change, since Davidlohr tied it to an
  independent bug report and the reporter quickly provided a Tested-by;
  there was no reason to wait for -rc2"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (122 commits)
  KVM: Move more code under CONFIG_HAVE_KVM_IRQFD
  KVM: nVMX: fix "acknowledge interrupt on exit" when APICv is in use
  KVM: nVMX: Fix nested vmexit ack intr before load vmcs01
  KVM: PPC: Enable IRQFD support for the XICS interrupt controller
  KVM: Give IRQFD its own separate enabling Kconfig option
  KVM: Move irq notifier implementation into eventfd.c
  KVM: Move all accesses to kvm::irq_routing into irqchip.c
  KVM: irqchip: Provide and use accessors for irq routing table
  KVM: Don't keep reference to irq routing table in irqfd struct
  KVM: PPC: drop duplicate tracepoint
  arm64: KVM: fix 64bit CP15 VM access for 32bit guests
  KVM: arm64: GICv3: mandate page-aligned GICV region
  arm64: KVM: GICv3: move system register access to msr_s/mrs_s
  KVM: PPC: PR: Handle FSCR feature deselects
  KVM: PPC: HV: Remove generic instruction emulation
  KVM: PPC: BOOKEHV: rename e500hv_spr to bookehv_spr
  KVM: PPC: Remove DCR handling
  KVM: PPC: Expose helper functions for data/inst faults
  KVM: PPC: Separate loadstore emulation from priv emulation
  KVM: PPC: Handle magic page in kvmppc_ld/st
  ...

Use the more generic functions get_signal() signal_setup_done()
for signal delivery.

Signed-off-by: Richard Weinberger <richard@nod.at>