Commit Graph

1278 Commits

Author SHA1 Message Date
Anthony Yznaga
a7159a87a3 sparc64: speed up etrap/rtrap on NG2 and later processors
For many sun4v processor types, reading or writing a privileged register
has a latency of 40 to 70 cycles.  Use a combination of the low-latency
allclean, otherw, normalw, and nop instructions in etrap and rtrap to
replace 2 rdpr and 5 wrpr instructions and improve etrap/rtrap
performance.  allclean, otherw, and normalw are available on NG2 and
later processors.

The average ticks to execute the flush windows trap ("ta 0x3") with and
without this patch on select platforms:

 CPU            Not patched     Patched    % Latency Reduction

 NG2            1762            1558            -11.58
 NG4            3619            3204            -11.47
 M7             3015            2624            -12.97
 SPARC64-X      829             770              -7.12

Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-09 20:20:11 -07:00
Nitin Gupta
df7b2155bb sparc64: Add 16GB hugepage support
Adds support for 16GB hugepage size. To use this page size
use kernel parameters as:

default_hugepagesz=16G hugepagesz=16G hugepages=10

Testing:

Tested with the stream benchmark which allocates 48G of
arrays backed by 16G hugepages and does RW operation on
them in parallel.

Orabug: 25362942

Cc: Anthony Yznaga <anthony.yznaga@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-15 21:48:07 -07:00
Nitin Gupta
44382b0195 sparc64: Support huge PUD case in get_user_pages
get_user_pages() is used to do direct IO. It already
handles the case where the address range is backed
by PMD huge pages. This patch now adds the case where
the range could be backed by PUD huge pages.

Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-15 21:48:06 -07:00
Jag Raman
5d171050e2 sparc64: vcc: Enable VCC port probe and removal
Enables VCC port probe and removal to initialize and terminate
VCC ports respectively. When a device/port matching the VCC driver
is added, the probe function is invoked along with a reference
to the device. remove function is called when the device is
removed.

Also add APIs to cache and retrieve VCC ports from a VCC table

Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-15 21:33:51 -07:00
David S. Miller
2f7043a377 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc 2017-08-10 12:09:13 -07:00
David S. Miller
4d9fbf539b sparc64: Revert 16GB huge page support.
It overflows the amount of space available in the initial .text section
of trap handler assembler in some configurations, resulting in build
failures.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-10 09:49:15 -07:00
Vijay Kumar
8536e02e91 sparc64: Use CPU_POKE to resume idle cpu
Use CPU_POKE hypervisor call to resume idle cpu if supported.

Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Reviewed-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 22:15:10 -07:00
Vijay Kumar
28d43de741 sparc64: Add a new hypercall CPU_POKE
This adds a new hypercall CPU_POKE for quickly waking up an idle CPU.
CPU_POKE should only be sent to valid non-local CPUs.

Signed-off-by: Rob Gardner <rob.gardner@oracle.com>
Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Reviewed-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 22:15:10 -07:00
Nitin Gupta
f10bb00790 sparc64: Add 16GB hugepage support
Adds support for 16GB hugepage size. To use this page size
use kernel parameters as:

default_hugepagesz=16G hugepagesz=16G hugepages=10

Testing:

Tested with the stream benchmark which allocates 48G of
arrays backed by 16G hugepages and does RW operation on
them in parallel.

Orabug: 25362942

Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 22:12:19 -07:00
Nitin Gupta
c9a844c510 sparc64: Support huge PUD case in get_user_pages
get_user_pages() is used to do direct IO. It already
handles the case where the address range is backed
by PMD huge pages. This patch now adds the case where
the range could be backed by PUD huge pages.

Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 22:11:11 -07:00
Allen Pais
7d484acb2f sparc64: recognize and support sparc M8 cpu type
Recognize SPARC-M8 cpu type, hardware caps and cpu
distribution map.

Signed-off-by: Allen Pais <allen.pais@oracle.com>
Signed-off-by: David Aldridge <david.j.aldridge@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-04 11:08:53 -07:00
Allen Pais
9e48cd4a77 sparc64: properly name the cpu constants
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Allen Pais <allen.pais@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-04 11:08:52 -07:00
Linus Torvalds
0a23ea65ce Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc fixes from David Miller:

 - block interrupts properly across the entire MMU context change (both
   the hw MMU context change and the TSB table change) so that we don't
   get a perf event interrupt in the middle. From Rob Gardner.

 - be sure to register hugepages early enough, from Nitin Gupta.

 - UltraSPARC-III user copy exception handling would return garbage for
   the copied length in some circumstances.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: Fix exception handling in UltraSPARC-III memcpy.
  sbus: Convert to using %pOF instead of full_name
  sparc: defconfig: Cleanup from old Kconfig options
  sparc64: Register hugepages during arch init
  sparc64: Prevent perf from running during super critical sections
2017-08-04 10:17:45 -07:00
Linus Torvalds
ae75d1aefe TTY/Serial fixes for 4.13-rc2
Here are some small tty and serial driver fixes for 4.13-rc2.  Nothing
 huge at all, a revert of a patch that turned out to break things, a fix
 up for a new tty ioctl we added in 4.13-rc1 to get the uapi definition
 correct, and a few minor serial driver fixes for reported issues.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are some small tty and serial driver fixes for 4.13-rc2. Nothing
  huge at all, a revert of a patch that turned out to break things, a
  fix up for a new tty ioctl we added in 4.13-rc1 to get the uapi
  definition correct, and a few minor serial driver fixes for reported
  issues.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-4.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: Fix TIOCGPTPEER ioctl definition
  tty: hide unused pty_get_peer function
  tty: serial: lpuart: Fix the logic for detecting the 32-bit type UART
  serial: imx: Prevent TX buffer PIO write when a DMA has been started
  Revert "serial: imx-serial - move DMA buffer configuration to DT"
  serial: sh-sci: Uninitialized variables in sysfs files
  serial: st-asc: Potential error pointer dereference
2017-07-22 09:00:24 -07:00
Rob Gardner
fc290a114f sparc64: Prevent perf from running during super critical sections
This fixes another cause of random segfaults and bus errors that may
occur while running perf with the callgraph option.

Critical sections beginning with spin_lock_irqsave() raise the interrupt
level to PIL_NORMAL_MAX (14) and intentionally do not block performance
counter interrupts, which arrive at PIL_NMI (15).

But some sections of code are "super critical" with respect to perf
because the perf_callchain_user() path accesses user space and may cause
TLB activity as well as faults as it unwinds the user stack.

One particular critical section occurs in switch_mm:

        spin_lock_irqsave(&mm->context.lock, flags);
        ...
        load_secondary_context(mm);
        tsb_context_switch(mm);
        ...
        spin_unlock_irqrestore(&mm->context.lock, flags);

If a perf interrupt arrives in between load_secondary_context() and
tsb_context_switch(), then perf_callchain_user() could execute with
the context ID of one process, but with an active TSB for a different
process. When the user stack is accessed, it is very likely to
incur a TLB miss, since the h/w context ID has been changed. The TLB
will then be reloaded with a translation from the TSB for one process,
but using a context ID for another process. This exposes memory from
one process to another, and since it is a mapping for stack memory,
this usually causes the new process to crash quickly.

This super critical section needs more protection than is provided
by spin_lock_irqsave() since perf interrupts must not be allowed in.

Since __tsb_context_switch already goes through the trouble of
disabling interrupts completely, we fix this by moving the secondary
context load down into this better protected region.

Orabug: 25577560

Signed-off-by: Dave Aldridge <david.j.aldridge@oracle.com>
Signed-off-by: Rob Gardner <rob.gardner@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-18 11:25:52 -07:00
Linus Torvalds
cb8c65ccff Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc fixes from David Miller:

 - Fix DMA regression in 4.13 merge window, only certain chips can do
   64-bit DMA. From Dave Dushar.

 - Correct cpu cross-call algorithm to correctly detect stalled or stuck
   remote cpus, from Jane Chu.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: Measure receiver forward progress to avoid send mondo timeout
  SPARC64: Fix sun4v DMA panic
2017-07-17 15:08:29 -07:00
Gleb Fotengauer-Malinovskiy
c632517923 tty: Fix TIOCGPTPEER ioctl definition
This ioctl does nothing to justify an _IOC_READ or _IOC_WRITE flag
because it doesn't copy anything from/to userspace to access the
argument.

Fixes: 54ebbfb160 ("tty: add TIOCGPTPEER ioctl")
Signed-off-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Acked-by: Aleksa Sarai <asarai@suse.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17 17:04:41 +02:00
Linus Torvalds
89cbec71fe Merge branch 'work.uaccess-unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull uacess-unaligned removal from Al Viro:
 "That stuff had just one user, and an exotic one, at that - binfmt_flat
  on arm and m68k"

* 'work.uaccess-unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  kill {__,}{get,put}_user_unaligned()
  binfmt_flat: flat_{get,put}_addr_from_rp() should be able to fail
2017-07-15 11:17:52 -07:00
Jane Chu
9d53caec84 sparc64: Measure receiver forward progress to avoid send mondo timeout
A large sun4v SPARC system may have moments of intensive xcall activities,
usually caused by unmapping many pages on many CPUs concurrently. This can
flood receivers with CPU mondo interrupts for an extended period, causing
some unlucky senders to hit send-mondo timeout. This problem gets worse
as cpu count increases because sometimes mappings must be invalidated on
all CPUs, and sometimes all CPUs may gang up on a single CPU.

But a busy system is not a broken system. In the above scenario, as long
as the receiver is making forward progress processing mondo interrupts,
the sender should continue to retry.

This patch implements the receiver's forward progress meter by introducing
a per cpu counter 'cpu_mondo_counter[cpu]' where 'cpu' is in the range
of 0..NR_CPUS. The receiver increments its counter as soon as it receives
a mondo and the sender tracks the receiver's counter. If the receiver has
stopped making forward progress when the retry limit is reached, the sender
declares send-mondo-timeout and panic; otherwise, the receiver is allowed
to keep making forward progress.

In addition, it's been observed that PCIe hotplug events generate Correctable
Errors that are handled by hypervisor and then OS. Hypervisor 'borrows'
a guest cpu strand briefly to provide the service. If the cpu strand is
simultaneously the only cpu targeted by a mondo, it may not be available
for the mondo in 20msec, causing SUN4V mondo timeout. It appears that 1 second
is the agreed wait time between hypervisor and guest OS, this patch makes
the adjustment.

Orabug: 25476541
Orabug: 26417466

Signed-off-by: Jane Chu <jane.chu@oracle.com>
Reviewed-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Reviewed-by: Rob Gardner <rob.gardner@oracle.com>
Reviewed-by: Thomas Tai <thomas.tai@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-14 11:18:02 -07:00
Linus Torvalds
80fc623809 Kbuild updates for v4.13 (2nd)
- Move generic-y of exported headers to uapi/asm/Kbuild
   for complete de-coupling of UAPI
 
 - Clean up scripts/Makefile.headersinst
 
 - Fix host programs for 32 bit machine with XFS file system
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Merge tag 'kbuild-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild updates from Masahiro Yamada:

 - Move generic-y of exported headers to uapi/asm/Kbuild for complete
   de-coupling of UAPI

 - Clean up scripts/Makefile.headersinst

 - Fix host programs for 32 bit machine with XFS file system

* tag 'kbuild-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (29 commits)
  kbuild: Enable Large File Support for hostprogs
  kbuild: remove wrapper files handling from Makefile.headersinst
  kbuild: split exported generic header creation into uapi-asm-generic
  kbuild: do not include old-kbuild-file from Makefile.headersinst
  xtensa: move generic-y of exported headers to uapi/asm/Kbuild
  unicore32: move generic-y of exported headers to uapi/asm/Kbuild
  tile: move generic-y of exported headers to uapi/asm/Kbuild
  sparc: move generic-y of exported headers to uapi/asm/Kbuild
  sh: move generic-y of exported headers to uapi/asm/Kbuild
  parisc: move generic-y of exported headers to uapi/asm/Kbuild
  openrisc: move generic-y of exported headers to uapi/asm/Kbuild
  nios2: move generic-y of exported headers to uapi/asm/Kbuild
  nios2: remove unneeded arch/nios2/include/(generated/)asm/signal.h
  microblaze: move generic-y of exported headers to uapi/asm/Kbuild
  metag: move generic-y of exported headers to uapi/asm/Kbuild
  m68k: move generic-y of exported headers to uapi/asm/Kbuild
  m32r: move generic-y of exported headers to uapi/asm/Kbuild
  ia64: remove redundant generic-y += kvm_para.h from asm/Kbuild
  hexagon: move generic-y of exported headers to uapi/asm/Kbuild
  h8300: move generic-y of exported headers to uapi/asm/Kbuild
  ...
2017-07-13 13:37:57 -07:00
Nicholas Piggin
f2e0cff85e kernel/watchdog: introduce arch_touch_nmi_watchdog()
For architectures that define HAVE_NMI_WATCHDOG, instead of having them
provide the complete touch_nmi_watchdog() function, just have them
provide arch_touch_nmi_watchdog().

This gives the generic code more flexibility in implementing this
function, and arch implementations don't miss out on touching the
softlockup watchdog or other generic details.

Link: http://lkml.kernel.org/r/20170616065715.18390-3-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Babu Moger <babu.moger@oracle.com>
Tested-by: Babu Moger <babu.moger@oracle.com>	[sparc]
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 16:26:02 -07:00
Linus Torvalds
3b06b1a744 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc fixes from David Miller:

 - Fix symbol version generation for assembler on sparc, from
   Nagarathnam Muthusamy.

 - Fix compound page handling in gup_huge_pmd(), from Nitin Gupta.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: Fix gup_huge_pmd
  Adding the type of exported symbols
  sed regex in Makefile.build requires line break between exported symbols
  Adding asm-prototypes.h for genksyms to generate crc
2017-07-11 21:34:24 -07:00
Masahiro Yamada
b6744e0414 sparc: move generic-y of exported headers to uapi/asm/Kbuild
Since commit fcc8487d47 ("uapi: export all headers under uapi
directories"), all (and only) headers under uapi directories are
exported, but asm-generic wrappers are still exceptions.

To complete de-coupling the uapi from kernel headers, move generic-y
of exported headers to uapi/asm/Kbuild.

With this change, "make headers_install" will just need to parse
uapi/asm/Kbuild to build up exported headers.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-07-11 21:33:52 +09:00
Linus Torvalds
fe1b518075 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next
Pull sparc updates from David Miller:

 1) Queued spinlocks and rwlocks for sparc64, from Babu Moger.

 2) Some const'ification from Arvind Yadav.

 3) LDC/VIO driver infrastructure changes to facilitate future upcoming
    drivers, from Jag Raman.

 4) Initialize sched_clock() et al. early so that the initial printk
    timestamps are all done while the implementation is available and
    functioning. From Pavel Tatashin.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next: (38 commits)
  sparc: kernel: pmc: make of_device_ids const.
  sparc64: fix typo in property
  sparc64: add port_id to VIO device metadata
  sparc64: Enhance search for VIO device in MDESC
  sparc64: enhance VIO device probing
  sparc64: check if a client is allowed to register for MDESC notifications
  sparc64: remove restriction on VIO device name size
  sparc64: refactor code to obtain cfg_handle property from MDESC
  sparc64: add MDESC node name property to VIO device metadata
  sparc64: mdesc: use __GFP_REPEAT action modifier for VM allocation
  sparc64: expand MDESC interface
  sparc64: skip handshake for LDC channels in RAW mode
  sparc64: specify the device class in VIO version info. packet
  sparc64: ensure VIO operations are defined while being used
  sparc: kernel: apc: make of_device_ids const
  sparc/time: make of_device_ids const
  sparc64: broken %tick frequency on spitfire cpus
  sparc64: use prom interface to get %stick frequency
  sparc64: optimize functions that access tick
  sparc64: add hot-patched and inlined get_tick()
  ...
2017-07-08 12:14:14 -07:00
Linus Torvalds
dc502142b6 Merge branch 'uaccess.strlen' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull user access str* updates from Al Viro:
 "uaccess str...() dead code removal"

* 'uaccess.strlen' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  s390 keyboard.c: don't open-code strndup_user()
  mips: get rid of unused __strnlen_user()
  get rid of unused __strncpy_from_user() instances
  kill strlen_user()
2017-07-06 22:07:44 -07:00
Linus Torvalds
f72e24a124 This is the first pull request for the new dma-mapping subsystem
In this new subsystem we'll try to properly maintain all the generic
 code related to dma-mapping, and will further consolidate arch code
 into common helpers.
 
 This pull request contains:
 
  - removal of the DMA_ERROR_CODE macro, replacing it with calls
    to ->mapping_error so that the dma_map_ops instances are
    more self contained and can be shared across architectures (me)
  - removal of the ->set_dma_mask method, which duplicates the
    ->dma_capable one in terms of functionality, but requires more
    duplicate code.
  - various updates for the coherent dma pool and related arm code
    (Vladimir)
  - various smaller cleanups (me)
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Merge tag 'dma-mapping-4.13' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping infrastructure from Christoph Hellwig:
 "This is the first pull request for the new dma-mapping subsystem

  In this new subsystem we'll try to properly maintain all the generic
  code related to dma-mapping, and will further consolidate arch code
  into common helpers.

  This pull request contains:

   - removal of the DMA_ERROR_CODE macro, replacing it with calls to
     ->mapping_error so that the dma_map_ops instances are more self
     contained and can be shared across architectures (me)

   - removal of the ->set_dma_mask method, which duplicates the
     ->dma_capable one in terms of functionality, but requires more
     duplicate code.

   - various updates for the coherent dma pool and related arm code
     (Vladimir)

   - various smaller cleanups (me)"

* tag 'dma-mapping-4.13' of git://git.infradead.org/users/hch/dma-mapping: (56 commits)
  ARM: dma-mapping: Remove traces of NOMMU code
  ARM: NOMMU: Set ARM_DMA_MEM_BUFFERABLE for M-class cpus
  ARM: NOMMU: Introduce dma operations for noMMU
  drivers: dma-mapping: allow dma_common_mmap() for NOMMU
  drivers: dma-coherent: Introduce default DMA pool
  drivers: dma-coherent: Account dma_pfn_offset when used with device tree
  dma: Take into account dma_pfn_offset
  dma-mapping: replace dmam_alloc_noncoherent with dmam_alloc_attrs
  dma-mapping: remove dmam_free_noncoherent
  crypto: qat - avoid an uninitialized variable warning
  au1100fb: remove a bogus dma_free_nonconsistent call
  MAINTAINERS: add entry for dma mapping helpers
  powerpc: merge __dma_set_mask into dma_set_mask
  dma-mapping: remove the set_dma_mask method
  powerpc/cell: use the dma_supported method for ops switching
  powerpc/cell: clean up fixed mapping dma_ops initialization
  tile: remove dma_supported and mapping_error methods
  xen-swiotlb: remove xen_swiotlb_set_dma_mask
  arm: implement ->dma_supported instead of ->set_dma_mask
  mips/loongson64: implement ->dma_supported instead of ->set_dma_mask
  ...
2017-07-06 19:20:54 -07:00
Linus Torvalds
5518b69b76 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Reasonably busy this cycle, but perhaps not as busy as in the 4.12
  merge window:

   1) Several optimizations for UDP processing under high load from
      Paolo Abeni.

   2) Support pacing internally in TCP when using the sch_fq packet
      scheduler for this is not practical. From Eric Dumazet.

   3) Support mutliple filter chains per qdisc, from Jiri Pirko.

   4) Move to 1ms TCP timestamp clock, from Eric Dumazet.

   5) Add batch dequeueing to vhost_net, from Jason Wang.

   6) Flesh out more completely SCTP checksum offload support, from
      Davide Caratti.

   7) More plumbing of extended netlink ACKs, from David Ahern, Pablo
      Neira Ayuso, and Matthias Schiffer.

   8) Add devlink support to nfp driver, from Simon Horman.

   9) Add RTM_F_FIB_MATCH flag to RTM_GETROUTE queries, from Roopa
      Prabhu.

  10) Add stack depth tracking to BPF verifier and use this information
      in the various eBPF JITs. From Alexei Starovoitov.

  11) Support XDP on qed device VFs, from Yuval Mintz.

  12) Introduce BPF PROG ID for better introspection of installed BPF
      programs. From Martin KaFai Lau.

  13) Add bpf_set_hash helper for TC bpf programs, from Daniel Borkmann.

  14) For loads, allow narrower accesses in bpf verifier checking, from
      Yonghong Song.

  15) Support MIPS in the BPF selftests and samples infrastructure, the
      MIPS eBPF JIT will be merged in via the MIPS GIT tree. From David
      Daney.

  16) Support kernel based TLS, from Dave Watson and others.

  17) Remove completely DST garbage collection, from Wei Wang.

  18) Allow installing TCP MD5 rules using prefixes, from Ivan
      Delalande.

  19) Add XDP support to Intel i40e driver, from Björn Töpel

  20) Add support for TC flower offload in nfp driver, from Simon
      Horman, Pieter Jansen van Vuuren, Benjamin LaHaise, Jakub
      Kicinski, and Bert van Leeuwen.

  21) IPSEC offloading support in mlx5, from Ilan Tayari.

  22) Add HW PTP support to macb driver, from Rafal Ozieblo.

  23) Networking refcount_t conversions, From Elena Reshetova.

  24) Add sock_ops support to BPF, from Lawrence Brako. This is useful
      for tuning the TCP sockopt settings of a group of applications,
      currently via CGROUPs"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1899 commits)
  net: phy: dp83867: add workaround for incorrect RX_CTRL pin strap
  dt-bindings: phy: dp83867: provide a workaround for incorrect RX_CTRL pin strap
  cxgb4: Support for get_ts_info ethtool method
  cxgb4: Add PTP Hardware Clock (PHC) support
  cxgb4: time stamping interface for PTP
  nfp: default to chained metadata prepend format
  nfp: remove legacy MAC address lookup
  nfp: improve order of interfaces in breakout mode
  net: macb: remove extraneous return when MACB_EXT_DESC is defined
  bpf: add missing break in for the TCP_BPF_SNDCWND_CLAMP case
  bpf: fix return in load_bpf_file
  mpls: fix rtm policy in mpls_getroute
  net, ax25: convert ax25_cb.refcount from atomic_t to refcount_t
  net, ax25: convert ax25_route.refcount from atomic_t to refcount_t
  net, ax25: convert ax25_uid_assoc.refcount from atomic_t to refcount_t
  net, sctp: convert sctp_ep_common.refcnt from atomic_t to refcount_t
  net, sctp: convert sctp_transport.refcnt from atomic_t to refcount_t
  net, sctp: convert sctp_chunk.refcnt from atomic_t to refcount_t
  net, sctp: convert sctp_datamsg.refcnt from atomic_t to refcount_t
  net, sctp: convert sctp_auth_bytes.refcnt from atomic_t to refcount_t
  ...
2017-07-05 12:31:59 -07:00
Linus Torvalds
9a715cd543 TTY/Serial patches for 4.13-rc1
Here is the large tty/serial patchset for 4.13-rc1.
 
 A lot of tty and serial driver updates are in here, along with some
 fixups for some __get/put_user usages that were reported.  Nothing huge,
 just lots of development by a number of different developers, full
 details in the shortlog.
 
 All of these have been in linux-next for a while.  There will be a merge
 issue with the arm-soc tree in the include/linux/platform_data/atmel.h
 file.  Stephen has sent out a fixup for it, so it shouldn't be that
 difficult to merge.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here is the large tty/serial patchset for 4.13-rc1.

  A lot of tty and serial driver updates are in here, along with some
  fixups for some __get/put_user usages that were reported. Nothing
  huge, just lots of development by a number of different developers,
  full details in the shortlog.

  All of these have been in linux-next for a while"

* tag 'tty-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (71 commits)
  tty: serial: lpuart: add a more accurate baud rate calculation method
  tty: serial: lpuart: add earlycon support for imx7ulp
  tty: serial: lpuart: add imx7ulp support
  dt-bindings: serial: fsl-lpuart: add i.MX7ULP support
  tty: serial: lpuart: add little endian 32 bit register support
  tty: serial: lpuart: refactor lpuart32_{read|write} prototype
  tty: serial: lpuart: introduce lpuart_soc_data to represent SoC property
  serial: imx-serial - move DMA buffer configuration to DT
  serial: imx: Enable RTSD only when needed
  serial: imx: Remove unused members from imx_port struct
  serial: 8250: 8250_omap: Fix race b/w dma completion and RX timeout
  serial: 8250: Fix THRE flag usage for CAP_MINI
  tty/serial: meson_uart: update to stable bindings
  dt-bindings: serial: Add bindings for the Amlogic Meson UARTs
  serial: Delete dead code for CIR serial ports
  serial: sirf: make of_device_ids const
  serial/mpsc: switch to dma_alloc_attrs
  tty: serial: Add Actions Semi Owl UART earlycon
  dt-bindings: serial: Document Actions Semi Owl UARTs
  tty/serial: atmel: make the driver DT only
  ...
2017-07-03 20:04:16 -07:00
Linus Torvalds
1b044f1cfc Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "A rather large update for timers/timekeeping:

   - compat syscall consolidation (Al Viro)

   - Posix timer consolidation (Christoph Helwig / Thomas Gleixner)

   - Cleanup of the device tree based initialization for clockevents and
     clocksources (Daniel Lezcano)

   - Consolidation of the FTTMR010 clocksource/event driver (Linus
     Walleij)

   - The usual set of small fixes and updates all over the place"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (93 commits)
  timers: Make the cpu base lock raw
  clocksource/drivers/mips-gic-timer: Fix an error code in 'gic_clocksource_of_init()'
  clocksource/drivers/fsl_ftm_timer: Unmap region obtained by of_iomap
  clocksource/drivers/tcb_clksrc: Make IO endian agnostic
  clocksource/drivers/sun4i: Switch to the timer-of common init
  clocksource/drivers/timer-of: Fix invalid iomap check
  Revert "ktime: Simplify ktime_compare implementation"
  clocksource/drivers: Fix uninitialized variable use in timer_of_init
  kselftests: timers: Add test for frequency step
  kselftests: timers: Fix inconsistency-check to not ignore first timestamp
  time: Add warning about imminent deprecation of CONFIG_GENERIC_TIME_VSYSCALL_OLD
  time: Clean up CLOCK_MONOTONIC_RAW time handling
  posix-cpu-timers: Make timespec to nsec conversion safe
  itimer: Make timeval to nsec conversion range limited
  timers: Fix parameter description of try_to_del_timer_sync()
  ktime: Simplify ktime_compare implementation
  clocksource/drivers/fttmr010: Factor out clock read code
  clocksource/drivers/fttmr010: Implement delay timer
  clocksource/drivers: Add timer-of common init routine
  clocksource/drivers/tcb_clksrc: Save timer context on suspend/resume
  ...
2017-07-03 16:14:51 -07:00
Al Viro
3170d8d226 kill {__,}{get,put}_user_unaligned()
no users left

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-07-03 18:44:22 -04:00
David S. Miller
b079115937 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
A set of overlapping changes in macvlan and the rocker
driver, nothing serious.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-30 12:43:08 -04:00
Tobias Klauser
6474924e2b arch: remove unused macro/function thread_saved_pc()
The only user of thread_saved_pc() in non-arch-specific code was removed
in commit 8243d55977 ("sched/core: Remove pointless printout in
sched_show_task()").  Remove the implementations as well.

Some architectures use thread_saved_pc() in their arch-specific code.
Leave their thread_saved_pc() intact.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-06-28 16:13:57 -07:00
Christoph Hellwig
b02c2b0bfd sparc: remove arch specific dma_supported implementations
Usually dma_supported decisions are done by the dma_map_ops instance.
Switch sparc to that model by providing a ->dma_supported instance for
sbus that always returns false, and implementations tailored to the sun4u
and sun4v cases for sparc64, and leave it unimplemented for PCI on
sparc32, which means always supported.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David S. Miller <davem@davemloft.net>
2017-06-28 06:54:39 -07:00
Christoph Hellwig
c6d333e084 sparc: remove leon_dma_ops
We can just use pci32_dma_ops directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David S. Miller <davem@davemloft.net>
2017-06-28 06:54:38 -07:00
Christoph Hellwig
ceaf481c4f sparc: implement ->mapping_error
DMA_ERROR_CODE is going to go away, so don't rely on it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David S. Miller <davem@davemloft.net>
2017-06-28 06:54:32 -07:00
Jag Raman
15c35e4ebb sparc64: add port_id to VIO device metadata
Add port_id field to VIO device metadata to identify the port of
VIO device.

Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-25 13:43:15 -07:00
Jag Raman
f4d29ca7de sparc64: Enhance search for VIO device in MDESC
Enhances search for VIO device in MDESC by leveraging already existing
MDESC APIs. Enhances changes in earlier patch,
"sparc: Machine description indices can vary", by using existing MD
search functions. It also specifies a match function, thereby
enabling device_find_child() to use it for the purpose of matching
device nodes in MDESC.

An API to find VDEV node in MDESC based on its md_node_info is also
added. It is planned to be used by VIO device clients in the future.

Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-25 13:43:14 -07:00
Jag Raman
aa512d5ede sparc64: enhance VIO device probing
- Allocate IRQs for VIO devices during probing.
- Allow clients to specify if IRQs would be allocated for a given
  VIO device.
- Cache the device handle of the root node of channel-devices sub-tree in
  Machine Description (MDESC).

Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-25 13:43:14 -07:00
Jag Raman
06f3c3ac60 sparc64: add MDESC node name property to VIO device metadata
Add the MDESC node name of MDESC client to VIO device metadata. It is
later used to uniquely identify a node in the MDESC. VIO & MDESC APIs
are updated to handle this node name.

Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-25 13:43:13 -07:00
Jag Raman
411cb4a0b3 sparc64: expand MDESC interface
Add the following two APIs to Machine Description (MDESC)
- mdesc_get_node: Searches for a node in the Machine
  Description tree based on given information about
  that node.
- mdesc_get_node_info: Retrieves information about a
  given node.

Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-25 13:43:12 -07:00
David Herrmann
28b5ba2aa0 net: introduce SO_PEERGROUPS getsockopt
This adds the new getsockopt(2) option SO_PEERGROUPS on SOL_SOCKET to
retrieve the auxiliary groups of the remote peer. It is designed to
naturally extend SO_PEERCRED. That is, the underlying data is from the
same credentials. Regarding its syntax, it is based on SO_PEERSEC. That
is, if the provided buffer is too small, ERANGE is returned and @optlen
is updated. Otherwise, the information is copied, @optlen is set to the
actual size, and 0 is returned.

While SO_PEERCRED (and thus `struct ucred') already returns the primary
group, it lacks the auxiliary group vector. However, nearly all access
controls (including kernel side VFS and SYSVIPC, but also user-space
polkit, DBus, ...) consider the entire set of groups, rather than just
the primary group. But this is currently not possible with pure
SO_PEERCRED. Instead, user-space has to work around this and query the
system database for the auxiliary groups of a UID retrieved via
SO_PEERCRED.

Unfortunately, there is no race-free way to query the auxiliary groups
of the PID/UID retrieved via SO_PEERCRED. Hence, the current user-space
solution is to use getgrouplist(3p), which itself falls back to NSS and
whatever is configured in nsswitch.conf(3). This effectively checks
which groups we *would* assign to the user if it logged in *now*. On
normal systems it is as easy as reading /etc/group, but with NSS it can
resort to quering network databases (eg., LDAP), using IPC or network
communication.

Long story short: Whenever we want to use auxiliary groups for access
checks on IPC, we need further IPC to talk to the user/group databases,
rather than just relying on SO_PEERCRED and the incoming socket. This
is unfortunate, and might even result in dead-locks if the database
query uses the same IPC as the original request.

So far, those recursions / dead-locks have been avoided by using
primitive IPC for all crucial NSS modules. However, we want to avoid
re-inventing the wheel for each NSS module that might be involved in
user/group queries. Hence, we would preferably make DBus (and other IPC
that supports access-management based on groups) work without resorting
to the user/group database. This new SO_PEERGROUPS ioctl would allow us
to make dbus-daemon work without ever calling into NSS.

Cc: Michal Sekletar <msekleta@redhat.com>
Cc: Simon McVittie <simon.mcvittie@collabora.co.uk>
Reviewed-by: Tom Gundersen <teg@jklm.no>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-21 11:38:41 -04:00
Thomas Gleixner
f0cd9ae5d0 Merge branch 'timers/urgent' into timers/core
Pick up dependent changes.
2017-06-21 09:07:52 +02:00
Nagarathnam Muthusamy
bdca8cc096 Adding asm-prototypes.h for genksyms to generate crc
This patch adds the prototypes of assembly defined functions to asm-prototypes.h.
Some prototypes are directly added as they are not present in any existing header
files.

Signed-off-by: Nagarathnam Muthusamy <nagarathnam.muthusamy@oracle.com>
Reviewed-by: Babu Moger <babu.moger@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-19 11:13:05 -07:00
Pavel Tatashin
4929c83a6c sparc64: add hot-patched and inlined get_tick()
Add the new get_tick() function that is hot-patched during boot based on
processor we are booting on.

Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-12 15:44:03 -07:00
Pavel Tatashin
89108c3423 sparc64: improve modularity tick options
This patch prepares the code for early boot time stamps by making it more
modular.

- init_tick_ops() to initialize struct sparc64_tick_ops
- new sparc64_tick_ops operation get_frequency() which returns a
  frequency

Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-12 15:44:03 -07:00
Pavel Tatashin
178bf2b9a2 sparc64: optimize loads in clock_sched()
In clock sched we now have three loads:
	- Function pointer
	- quotient for multiplication
	- offset

However, it is possible to improve performance substantially, by
guaranteeing that all three loads are from the same cacheline.

By moving these three values first in sparc64_tick_ops, and by having
tick_operations 64-byte aligned we guarantee this.

Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Shannon Nelson <shannon.nelson@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-12 15:44:02 -07:00
Pavel Tatashin
68a792174d sparc64: remove trailing white spaces
A few changes that were reported by checkpatch, removed all trailing white
spaces in these two files.

Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-12 15:44:01 -07:00
Jag Raman
85762a65c1 sparc64: expand LDC interface
Add the following LDC APIs which are planned to be used by
LDC clients in the future:
- ldc_set_state: Sets given LDC channel to given state
- ldc_mode: Returns the mode of given LDC channel
- ldc_print: Prints info about given LDC channel
- ldc_rx_reset: Reset the RX queue of given LDC channel

Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Aaron Young <aaron.young@oracle.com>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-10 14:10:54 -07:00
David S. Miller
95c4629d92 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc 2017-06-10 14:06:46 -07:00
Aleksa Sarai
54ebbfb160 tty: add TIOCGPTPEER ioctl
When opening the slave end of a PTY, it is not possible for userspace to
safely ensure that /dev/pts/$num is actually a slave (in cases where the
mount namespace in which devpts was mounted is controlled by an
untrusted process). In addition, there are several unresolvable
race conditions if userspace were to attempt to detect attacks through
stat(2) and other similar methods [in addition it is not clear how
userspace could detect attacks involving FUSE].

Resolve this by providing an interface for userpace to safely open the
"peer" end of a PTY file descriptor by using the dentry cached by
devpts. Since it is not possible to have an open master PTY without
having its slave exposed in /dev/pts this interface is safe. This
interface currently does not provide a way to get the master pty (since
it is not clear whether such an interface is safe or even useful).

Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Valentin Rothberg <vrothberg@suse.com>
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09 12:27:54 +02:00