At Linux Plumbers, Andy Lutomirski approached me and pointed out that the
function call syscall_get_arguments() implemented in x86 was horribly
written and not optimized for the standard case of passing in 0 and 6 for
the starting index and the number of system calls to get. When looking at
all the users of this function, I discovered that all instances pass in only
0 and 6 for these arguments. Instead of having this function handle
different cases that are never used, simply rewrite it to return the first 6
arguments of a system call.

This should help out the performance of tracing system calls by ptrace,
ftrace and perf.

Link: http://lkml.kernel.org/r/20161107213233.754809394@goodmis.org

Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Dave Martin <dave.martin@arm.com>
Cc: "Dmitry V. Levin" <ldv@altlinux.org>
Cc: x86@kernel.org
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: uclinux-h8-devel@lists.sourceforge.jp
Cc: linux-hexagon@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: nios2-dev@lists.rocketboards.org
Cc: openrisc@lists.librecores.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-riscv@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: linux-um@lists.infradead.org
Cc: linux-xtensa@linux-xtensa.org
Cc: linux-arch@vger.kernel.org
Acked-by: Paul Burton <paul.burton@mips.com> # MIPS parts
Acked-by: Max Filippov <jcmvbkbc@gmail.com> # For xtensa changes
Acked-by: Will Deacon <will.deacon@arm.com> # For the arm64 bits
Reviewed-by: Thomas Gleixner <tglx@linutronix.de> # for x86
Reviewed-by: Dmitry V. Levin <ldv@altlinux.org>
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Pull MIPS fixes from Paul Burton:
 "A small batch of MIPS fixes for 5.1:

   - An interrupt masking fix for Loongson-based Lemote 2F systems
     (fixing a regression from v3.19)

   - A relocation fix for configurations in which the devicetree is
     stored in an ELF section (fixing a regression from v4.7)

   - Fix jump labels for MIPSr6 kernels where they previously could
     inadvertently place a control transfer instruction in a forbidden
     slot & take unexpected exceptions (fixing MIPSr6 support added in
     v4.0)

   - Extend an existing USB power workaround for the Netgear WNDR3400 to
     v2 boards in addition to the v3 ones that already used it

   - Remove the custom MIPS32 definition of __kernel_fsid_t to make it
     consistent with MIPS64 & every other architecture, in particular
     resolving issues for code which tries to print the val field whose
     type previously differed (though had identical memory layout)"

* tag 'mips_fixes_5.1_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: Remove custom MIPS32 __kernel_fsid_t type
  mips: bcm47xx: Enable USB power on Netgear WNDR3400v2
  MIPS: Fix kernel crash for R6 in jump label branch function
  MIPS: Ensure ELF appended dtb is relocated
  mips: loongson64: lemote-2f: Add IRQF_NO_SUSPEND to "cascade" irqaction.

Pull more Kbuild updates from Masahiro Yamada:

 - add more Build-Depends to Debian source package

 - prefix header search paths with $(srctree)/

 - make modpost show verbose section mismatch warnings

 - avoid hard-coded CROSS_COMPILE for h8300

 - fix regression for Debian make-kpkg command

 - add semantic patch to detect missing put_device()

 - fix some warnings of 'make deb-pkg'

 - optimize NOSTDINC_FLAGS evaluation

 - add warnings about redundant generic-y

 - clean up Makefiles and scripts

* tag 'kbuild-v5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig: remove stale lxdialog/.gitignore
  kbuild: force all architectures except um to include mandatory-y
  kbuild: warn redundant generic-y
  Revert "modsign: Abort modules_install when signing fails"
  kbuild: Make NOSTDINC_FLAGS a simply expanded variable
  kbuild: deb-pkg: avoid implicit effects
  coccinelle: semantic code search for missing put_device()
  kbuild: pkg: grep include/config/auto.conf instead of $KCONFIG_CONFIG
  kbuild: deb-pkg: introduce is_enabled and if_enabled_echo to builddeb
  kbuild: deb-pkg: add CONFIG_ prefix to kernel config options
  kbuild: add workaround for Debian make-kpkg
  kbuild: source include/config/auto.conf instead of ${KCONFIG_CONFIG}
  unicore32: simplify linker script generation for decompressor
  h8300: use cc-cross-prefix instead of hardcoding h8300-unknown-linux-
  kbuild: move archive command to scripts/Makefile.lib
  modpost: always show verbose warning for section mismatch
  ia64: prefix header search path with $(srctree)/
  libfdt: prefix header search paths with $(srctree)/
  deb-pkg: generate correct build dependencies

Currently, every arch/*/include/uapi/asm/Kbuild explicitly includes
the common Kbuild.asm file. Factor out the duplicated include directives
to scripts/Makefile.asm-generic so that no architecture would opt out
of the mandatory-y mechanism.

um is not forced to include mandatory-y since it is a very exceptional
case which does not support UAPI.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Pull KVM updates from Paolo Bonzini:
 "ARM:
   - some cleanups
   - direct physical timer assignment
   - cache sanitization for 32-bit guests

  s390:
   - interrupt cleanup
   - introduction of the Guest Information Block
   - preparation for processor subfunctions in cpu models

  PPC:
   - bug fixes and improvements, especially related to machine checks
     and protection keys

  x86:
   - many, many cleanups, including removing a bunch of MMU code for
     unnecessary optimizations
   - AVIC fixes

  Generic:
   - memcg accounting"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (147 commits)
  kvm: vmx: fix formatting of a comment
  KVM: doc: Document the life cycle of a VM and its resources
  MAINTAINERS: Add KVM selftests to existing KVM entry
  Revert "KVM/MMU: Flush tlb directly in the kvm_zap_gfn_range()"
  KVM: PPC: Book3S: Add count cache flush parameters to kvmppc_get_cpu_char()
  KVM: PPC: Fix compilation when KVM is not enabled
  KVM: Minor cleanups for kvm_main.c
  KVM: s390: add debug logging for cpu model subfunctions
  KVM: s390: implement subfunction processor calls
  arm64: KVM: Fix architecturally invalid reset value for FPEXC32_EL2
  KVM: arm/arm64: Remove unused timer variable
  KVM: PPC: Book3S: Improve KVM reference counting
  KVM: PPC: Book3S HV: Fix build failure without IOMMU support
  Revert "KVM: Eliminate extra function calls in kvm_get_dirty_log_protect()"
  x86: kvmguest: use TSC clocksource if invariant TSC is exposed
  KVM: Never start grow vCPU halt_poll_ns from value below halt_poll_ns_grow_start
  KVM: Expose the initial start value in grow_halt_poll_ns() as a module parameter
  KVM: grow_halt_poll_ns() should never shrink vCPU halt_poll_ns
  KVM: x86/mmu: Consolidate kvm_mmu_zap_all() and kvm_mmu_zap_mmio_sptes()
  KVM: x86/mmu: WARN if zapping a MMIO spte results in zapping children
  ...

For MIPS32 kernels we have a custom definition of __kernel_fsid_t. This
differs from the asm-generic version used by all other architectures &
MIPS64 in one way - it declares the val field as an array of long,
rather than an array of int. Since int & long have identical size &
alignment when targeting MIPS32 anyway, this makes little sense.

Beyond the pointlessness this causes problems for code which prints
entries from the val array, for example the fanotify_encode_fid()
function [1]. If such code uses a format specified suited to an int then
it encounters compiler warnings when building for MIPS32, such as:

  In file included from include/linux/kernel.h:14:0,
                   from include/linux/list.h:9,
                   from include/linux/preempt.h:11,
                   from include/linux/spinlock.h:51,
                   from include/linux/fdtable.h:11,
                   from fs/notify/fanotify/fanotify.c:3:
  fs/notify/fanotify/fanotify.c: In function 'fanotify_encode_fid':
  include/linux/kern_levels.h:5:18: warning: format '%x' expects argument
    of type 'unsigned int', but argument 2 has type 'long int' [-Wformat=]

Remove the custom __kernel_fsid_t definition & make use of the
asm-generic version which will have an identical layout in memory
anyway, in order to remove the inconsistency with other architectures.

One possible regression this could cause if is any code is attempting to
print entries from the val array with a long-sized format specifier, in
which case it would begin seeing compiler warnings when built against
kernel headers including this change. Since such code is exceedingly
rare, and would have to be MIPS32-specific to expect a long, this seems
to be a problem that it's extremely unlikely anyone will encounter.

[1] https://lore.kernel.org/linux-mips/CAOQ4uxiEkczB7PNCXegFC-eYb9zAGaio_o=OgHAJHFd7eavBxA@mail.gmail.com/T/#mb43103277c79ef06b884359209e817db1c136140

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jan Kara <jack@suse.cz>
Cc: linux-arch@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org

Pull networking fixes from David Miller:
 "More fixes in the queue:

  1) Netfilter nat can erroneously register the device notifier twice,
     fix from Florian Westphal.

  2) Use after free in nf_tables, from Pablo Neira Ayuso.

  3) Parallel update of steering rule fix in mlx5 river, from Eli
     Britstein.

  4) RX processing panic in lan743x, fix from Bryan Whitehead.

  5) Use before initialization of TCP_SKB_CB, fix from Christoph Paasch.

  6) Fix locking in SRIOV mode of mlx4 driver, from Jack Morgenstein.

  7) Fix TX stalls in lan743x due to mishandling of interrupt ACKing
     modes, from Bryan Whitehead.

  8) Fix infoleak in l2tp_ip6_recvmsg(), from Eric Dumazet"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (43 commits)
  pptp: dst_release sk_dst_cache in pptp_sock_destruct
  MAINTAINERS: GENET & SYSTEMPORT: Add internal Broadcom list
  l2tp: fix infoleak in l2tp_ip6_recvmsg()
  net/tls: Inform user space about send buffer availability
  net_sched: return correct value for *notify* functions
  lan743x: Fix TX Stall Issue
  net/mlx4_core: Fix qp mtt size calculation
  net/mlx4_core: Fix locking in SRIOV mode when switching between events and polling
  net/mlx4_core: Fix reset flow when in command polling mode
  mlxsw: minimal: Initialize base_mac
  mlxsw: core: Prevent duplication during QSFP module initialization
  net: dwmac-sun8i: fix a missing check of of_get_phy_mode
  net: sh_eth: fix a missing check of of_get_phy_mode
  net: 8390: fix potential NULL pointer dereferences
  net: fujitsu: fix a potential NULL pointer dereference
  net: qlogic: fix a potential NULL pointer dereference
  isdn: hfcpci: fix potential NULL pointer dereference
  Documentation: devicetree: add a new optional property for port mac address
  net: rocker: fix a potential NULL pointer dereference
  net: qlge: fix a potential NULL pointer dereference
  ...

Insert Branch instruction instead of NOP to make sure assembler don't
patch code in forbidden slot. In jump label function, it might
be possible to patch Control Transfer Instructions(CTIs) into
forbidden slot, which will generate Reserved Instruction exception
in MIPS release 6.

Signed-off-by: Archer Yan <ayan@wavecomp.com>
Reviewed-by: Paul Burton <paul.burton@mips.com>
[paul.burton@mips.com:
  - Add MIPS prefix to subject.
  - Mark for stable from v4.0, which introduced r6 support, onwards.]
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: stable@vger.kernel.org # v4.0+

Referencing the __kernel_long_t type caused some user space applications
to stop compiling when they had not already included linux/posix_types.h,
e.g.

s/multicast.c -o ext/sockets/multicast.lo
In file included from /builddir/build/BUILD/php-7.3.3/main/php.h:468,
                 from /builddir/build/BUILD/php-7.3.3/ext/sockets/sockets.c:27:
/builddir/build/BUILD/php-7.3.3/ext/sockets/sockets.c: In function 'zm_startup_sockets':
/builddir/build/BUILD/php-7.3.3/ext/sockets/sockets.c:776:40: error: '__kernel_long_t' undeclared (first use in this function)
  776 |  REGISTER_LONG_CONSTANT("SO_SNDTIMEO", SO_SNDTIMEO, CONST_CS | CONST_PERSISTENT);

It is safe to include that header here, since it only contains kernel
internal types that do not conflict with other user space types.

It's still possible that some related build failures remain, but those
are likely to be for code that is not already y2038 safe.

Reported-by: Laura Abbott <labbott@redhat.com>
Fixes: a9beb86ae6e5 ("sock: Add SO_RCVTIMEO_NEW and SO_SNDTIMEO_NEW")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull DMA mapping updates from Christoph Hellwig:

 - add debugfs support for dumping dma-debug information (Corentin
   Labbe)

 - Kconfig cleanups (Andy Shevchenko and me)

 - debugfs cleanups (Greg Kroah-Hartman)

 - improve dma_map_resource and use it in the media code

 - arch_setup_dma_ops / arch_teardown_dma_ops cleanups

 - various small cleanups and improvements for the per-device coherent
   allocator

 - make the DMA mask an upper bound and don't fail "too large" dma mask
   in the remaning two architectures - this will allow big driver
   cleanups in the following merge windows

* tag 'dma-mapping-5.1' of git://git.infradead.org/users/hch/dma-mapping: (21 commits)
  Documentation/DMA-API-HOWTO: update dma_mask sections
  sparc64/pci_sun4v: allow large DMA masks
  sparc64/iommu: allow large DMA masks
  sparc64: refactor the ali DMA quirk
  ccio: allow large DMA masks
  dma-mapping: remove the DMA_MEMORY_EXCLUSIVE flag
  dma-mapping: remove dma_mark_declared_memory_occupied
  dma-mapping: move CONFIG_DMA_CMA to kernel/dma/Kconfig
  dma-mapping: improve selection of dma_declare_coherent availability
  dma-mapping: remove an incorrect __iommem annotation
  of: select OF_RESERVED_MEM automatically
  device.h: dma_mem is only needed for HAVE_GENERIC_DMA_COHERENT
  mfd/sm501: depend on HAS_DMA
  dma-mapping: add a kconfig symbol for arch_teardown_dma_ops availability
  dma-mapping: add a kconfig symbol for arch_setup_dma_ops availability
  dma-mapping: move debug configuration options to kernel/dma
  dma-debug: add dumping facility via debugfs
  dma: debug: no need to check return value of debugfs_create functions
  videobuf2: replace a layering violation with dma_map_resource
  dma-mapping: don't BUG when calling dma_map_resource on RAM
  ...