Commit Graph

130 Commits

Author SHA1 Message Date
Linus Torvalds
9977d9b379 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull big execve/kernel_thread/fork unification series from Al Viro:
 "All architectures are converted to new model.  Quite a bit of that
  stuff is actually shared with architecture trees; in such cases it's
  literally shared branch pulled by both, not a cherry-pick.

  A lot of ugliness and black magic is gone (-3KLoC total in this one):

   - kernel_thread()/kernel_execve()/sys_execve() redesign.

     We don't do syscalls from kernel anymore for either kernel_thread()
     or kernel_execve():

     kernel_thread() is essentially clone(2) with callback run before we
     return to userland, the callbacks either never return or do
     successful do_execve() before returning.

     kernel_execve() is a wrapper for do_execve() - it doesn't need to
     do transition to user mode anymore.

     As a result kernel_thread() and kernel_execve() are
     arch-independent now - they live in kernel/fork.c and fs/exec.c
     resp.  sys_execve() is also in fs/exec.c and it's completely
     architecture-independent.

   - daemonize() is gone, along with its parts in fs/*.c

   - struct pt_regs * is no longer passed to do_fork/copy_process/
     copy_thread/do_execve/search_binary_handler/->load_binary/do_coredump.

   - sys_fork()/sys_vfork()/sys_clone() unified; some architectures
     still need wrappers (ones with callee-saved registers not saved in
     pt_regs on syscall entry), but the main part of those suckers is in
     kernel/fork.c now."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (113 commits)
  do_coredump(): get rid of pt_regs argument
  print_fatal_signal(): get rid of pt_regs argument
  ptrace_signal(): get rid of unused arguments
  get rid of ptrace_signal_deliver() arguments
  new helper: signal_pt_regs()
  unify default ptrace_signal_deliver
  flagday: kill pt_regs argument of do_fork()
  death to idle_regs()
  don't pass regs to copy_process()
  flagday: don't pass regs to copy_thread()
  bfin: switch to generic vfork, get rid of pointless wrappers
  xtensa: switch to generic clone()
  openrisc: switch to use of generic fork and clone
  unicore32: switch to generic clone(2)
  score: switch to generic fork/vfork/clone
  c6x: sanitize copy_thread(), get rid of clone(2) wrapper, switch to generic clone()
  take sys_fork/sys_vfork/sys_clone prototypes to linux/syscalls.h
  mn10300: switch to generic fork/vfork/clone
  h8300: switch to generic fork/vfork/clone
  tile: switch to generic clone()
  ...

Conflicts:
	arch/microblaze/include/asm/Kbuild
2012-12-12 12:22:13 -08:00
Linus Torvalds
090f8ccba3 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "Lots of activity:

   211 files changed, 8328 insertions(+), 4116 deletions(-)

  most of it on the tooling side.

  Main changes:

   * ftrace enhancements and fixes from Steve Rostedt.

   * uprobes fixes, cleanups and preparation for the ARM port from Oleg
     Nesterov.

   * UAPI fixes, from David Howels - prepares the arch/x86 UAPI
     transition

   * Separate perf tests into multiple objects, one per test, from Jiri
     Olsa.

   * Make hardware event translations available in sysfs, from Jiri
     Olsa.

   * Fixes to /proc/pid/maps parsing, preparatory to supporting data
     maps, from Namhyung Kim

   * Implement ui_progress for GTK, from Namhyung Kim

   * Add framework for automated perf_event_attr tests, where tools with
     different command line options will be run from a 'perf test', via
     python glue, and the perf syscall will be intercepted to verify
     that the perf_event_attr fields set by the tool are those expected,
     from Jiri Olsa

   * Add a 'link' method for hists, so that we can have the leader with
     buckets for all the entries in all the hists.  This new method is
     now used in the default 'diff' output, making the sum of the
     'baseline' column be 100%, eliminating blind spots.

   * libtraceevent fixes for compiler warnings trying to make perf it
     build on some distros, like fedora 14, 32-bit, some of the warnings
     really pointed to real bugs.

   * Add a browser for 'perf script' and make it available from the
     report and annotate browsers.  It does filtering to find the
     scripts that handle events found in the perf.data file used.  From
     Feng Tang

   * perf inject changes to allow showing where a task sleeps, from
     Andrew Vagin.

   * Makefile improvements from Namhyung Kim.

   * Add --pre and --post command hooks in 'stat', from Peter Zijlstra.

   * Don't stop synthesizing threads when one vanishes, this is for the
     existing threads when we start a tool like trace.

   * Use sched:sched_stat_runtime to provide a thread summary, this
     produces the same output as the 'trace summary' subcommand of
     tglx's original "trace" tool.

   * Support interrupted syscalls in 'trace'

   * Add an event duration column and filter in 'trace'.

   * There are references to the man pages in some tools, so try to
     build Documentation when installing, warning the user if that is
     not possible, from Borislav Petkov.

   * Give user better message if precise is not supported, from David
     Ahern.

   * Try to find cross-built objdump path by using the session
     environment information in the perf.data file header, from Irina
     Tirdea, original patch and idea by Namhyung Kim.

   * Diplays more output on features check for make V=1, so that one can
     figure out what is happening by looking at gcc output, etc.  From
     Jiri Olsa.

   * Add on_exit implementation for systems without one, e.g.  Android,
     from Bernhard Rosenkraenzer.

   * Only process events for vcpus of interest, helps handling large
     number of events, from David Ahern.

   * Cross compilation fixes for Android, from Irina Tirdea.

   * Add documentation on compiling for Android, from Irina Tirdea.

   * perf diff improvements from Jiri Olsa.

   * Target (task/user/cpu/syswide) handling improvements, from Namhyung
     Kim.

   * Add support in 'trace' for tracing workload given by command line,
     from Namhyung Kim.

   * ... and much more."

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (194 commits)
  uprobes: Use percpu_rw_semaphore to fix register/unregister vs dup_mmap() race
  perf evsel: Introduce is_group_member method
  perf powerpc: Use uapi/unistd.h to fix build error
  tools: Pass the target in descend
  tools: Honour the O= flag when tool build called from a higher Makefile
  tools: Define a Makefile function to do subdir processing
  perf ui: Always compile browser setup code
  perf ui: Add ui_progress__finish()
  perf ui gtk: Implement ui_progress functions
  perf ui: Introduce generic ui_progress helper
  perf ui tui: Move progress.c under ui/tui directory
  perf tools: Add basic event modifier sanity check
  perf tools: Omit group members from perf_evlist__disable/enable
  perf tools: Ensure single disable call per event in record comand
  perf tools: Fix 'disabled' attribute config for record command
  perf tools: Fix attributes for '{}' defined event groups
  perf tools: Use sscanf for parsing /proc/pid/maps
  perf tools: Add gtk.<command> config option for launching GTK browser
  perf tools: Fix compile error on NO_NEWT=1 build
  perf hists: Initialize all of he->stat with zeroes
  ...
2012-12-11 18:14:31 -08:00
Linus Torvalds
b58ed041a3 Device tree changes for v3.8
Bug fixes, little cleanups, and documentation changes. The most invasive
 thing here touches a bunch of the arch directories to use a common build
 rule for .dtb files. There are no major changes to functionality here
 other than a ew new helper functions.
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Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux-2.6

Pull device tree changes from Grant Likely:
 "Here are the DT changes I've got queued up for v3.8.  As described
  below, there are a lot of bug fixes here and documentation updates but
  nothing major:

  Bug fixes, little cleanups, and documentation changes.  The most
  invasive thing here touches a bunch of the arch directories to use a
  common build rule for .dtb files.  There are no major changes to
  functionality here other than a few new helper functions."

* tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux-2.6: (34 commits)
  arm64: Fix the dtbs target building
  mtd: nand: davinci: fix the binding documentation
  rtc: rtc-mv: Add the device tree binding documentation
  devicetree/bindings: Move gpio-leds binding into leds directory
  of/vendor-prefixes: add Imagination Technologies
  microblaze: use new common dtc rule
  c6x: use new common dtc rule
  openrisc: use new common dtc rule
  arm64: Add dtbs target for building all the enabled dtb files
  arm64: use new common dtc rule
  ARM: dt: change .dtb build rules to build in dts directory
  kbuild: centralize .dts->.dtb rule
  Fix build when CONFIG_W1_MASTER_GPIO=m b exporting "allnodes"
  of/spi: Honour "status=disabled" property of device
  of_mdio: Honour "status=disabled" property of device
  of_i2c: Honour "status=disabled" property of device
  powerpc: Fix fallout from device_node->name constification
  of: add 'const' for of_parse_phandle parameter *np
  Documentation: correct of_platform_populate() argument list
  script: dtc: clean generated files
  ...
2012-12-11 11:30:41 -08:00
Ingo Molnar
cc1b39dbf9 Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core
Pull ftrace updates from Steve Rostedt.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-12-08 15:54:35 +01:00
Stephen Warren
19fbd6b296 openrisc: use new common dtc rule
The current rules have the .dtb files build in a different directory
from the .dts files. This patch changes openrisc to use the generic dtb
rule which builds .dtb files in the same directory as the source .dts.

This requires renaming arch/openrisc/boot/Makefile to
arch/openrisc/boot/dts/Makefile, and updating arch/openrisc/Makefile to
call the new Makefile.

Cc: Jonas Bonn <jonas@southpole.se>
Cc: linux@lists.openrisc.net
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2012-12-03 17:17:48 -06:00
Al Viro
afa86fc426 flagday: don't pass regs to copy_thread()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 23:43:42 -05:00
Al Viro
39d91a9eaf openrisc: switch to use of generic fork and clone
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 23:43:40 -05:00
Al Viro
910cdc553a kill stray kernel_thread() garbage
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 21:53:36 -05:00
Al Viro
f4091322d7 Merge branches 'no-rebases', 'arch-avr32', 'arch-blackfin', 'arch-cris', 'arch-h8300', 'arch-m32r', 'arch-mn10300', 'arch-score', 'arch-sh' and 'arch-powerpc' into for-next 2012-11-28 21:52:07 -05:00
Al Viro
d26654e5f9 openrisk: fix altstack switching on sigreturn
do_sigaltstack() expects _userland_ address, TYVM...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 21:46:11 -05:00
David Sharp
8cbd9cc625 tracing,x86: Add a TSC trace_clock
In order to promote interoperability between userspace tracers and ftrace,
add a trace_clock that reports raw TSC values which will then be recorded
in the ring buffer. Userspace tracers that also record TSCs are then on
exactly the same time base as the kernel and events can be unambiguously
interlaced.

Tested: Enabled a tracepoint and the "tsc" trace_clock and saw very large
timestamp values.

v2:
Move arch-specific bits out of generic code.
v3:
Rename "x86-tsc", cleanups
v7:
Generic arch bits in Kbuild.

Google-Bug-Id: 6980623
Link: http://lkml.kernel.org/r/1352837903-32191-1-git-send-email-dhsharp@google.com

Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@linux.intel.com>
Signed-off-by: David Sharp <dhsharp@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-11-13 15:48:27 -05:00
Jonas Bonn
a91a2bb1db openrisc: use generic sys_execve
Signed-off-by: Jonas Bonn <jonas@southpole.se>
2012-10-19 18:33:01 +02:00
Jonas Bonn
cbf23cf1b9 openrisc: use generic kernel_thread/kernel_execve
Signed-off-by: Jonas Bonn <jonas@southpole.se>
2012-10-19 18:32:36 +02:00
Jonas Bonn
287ad220cd openrisc: pass correct arg to schedule_tail
schedule_tail() requires that the 'prev' task be passed as an argument
to it.  This arg is set in _switch, just before 'returning' to one of
the ret_* functions where schedule_tail is invoked.

Signed-off-by: Jonas Bonn <jonas@southpole.se>
2012-10-19 18:32:36 +02:00
Linus Torvalds
d25282d1c9 Merge branch 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module signing support from Rusty Russell:
 "module signing is the highlight, but it's an all-over David Howells frenzy..."

Hmm "Magrathea: Glacier signing key". Somebody has been reading too much HHGTTG.

* 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (37 commits)
  X.509: Fix indefinite length element skip error handling
  X.509: Convert some printk calls to pr_devel
  asymmetric keys: fix printk format warning
  MODSIGN: Fix 32-bit overflow in X.509 certificate validity date checking
  MODSIGN: Make mrproper should remove generated files.
  MODSIGN: Use utf8 strings in signer's name in autogenerated X.509 certs
  MODSIGN: Use the same digest for the autogen key sig as for the module sig
  MODSIGN: Sign modules during the build process
  MODSIGN: Provide a script for generating a key ID from an X.509 cert
  MODSIGN: Implement module signature checking
  MODSIGN: Provide module signing public keys to the kernel
  MODSIGN: Automatically generate module signing keys if missing
  MODSIGN: Provide Kconfig options
  MODSIGN: Provide gitignore and make clean rules for extra files
  MODSIGN: Add FIPS policy
  module: signature checking hook
  X.509: Add a crypto key parser for binary (DER) X.509 certificates
  MPILIB: Provide a function to read raw data into an MPI
  X.509: Add an ASN.1 decoder
  X.509: Add simple ASN.1 grammar compiler
  ...
2012-10-14 13:39:34 -07:00
Jonas Bonn
6257c5740e UAPI Disintegration 2012-10-09
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Merge tag 'disintegrate-openrisc-20121009' of git://git.infradead.org/users/dhowells/linux-headers

UAPI Disintegration 2012-10-09

* tag 'disintegrate-openrisc-20121009' of git://git.infradead.org/users/dhowells/linux-headers:
  UAPI: (Scripted) Disintegrate arch/openrisc/include/asm
2012-10-13 07:38:37 +02:00
Linus Torvalds
18a022de47 OpenRISC updates for 3.7
Fixups for some corner cases, build issues, and some obvious bugs in
 IRQ handling.  No major changes.
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Merge tag 'for-3.7' of git://openrisc.net/jonas/linux

Pull OpenRISC updates from Jonas Bonn:
 "Fixups for some corner cases, build issues, and some obvious bugs in
  IRQ handling.  No major changes."

* tag 'for-3.7' of git://openrisc.net/jonas/linux:
  openrisc: mask interrupts in irq_mask_ack function
  openrisc: fix typos in comments and warnings
  openrisc: PIC should act on domain-local irqs
  openrisc: Make cpu_relax() invoke barrier()
  audit: define AUDIT_ARCH_OPENRISC
  openrisc: delay: fix handling of counter overflow
  openrisc: delay: fix loops calculation for __const_udelay
2012-10-13 11:25:41 +09:00
Jeff Layton
91a27b2a75 vfs: define struct filename and have getname() return it
getname() is intended to copy pathname strings from userspace into a
kernel buffer. The result is just a string in kernel space. It would
however be quite helpful to be able to attach some ancillary info to
the string.

For instance, we could attach some audit-related info to reduce the
amount of audit-related processing needed. When auditing is enabled,
we could also call getname() on the string more than once and not
need to recopy it from userspace.

This patchset converts the getname()/putname() interfaces to return
a struct instead of a string. For now, the struct just tracks the
string in kernel space and the original userland pointer for it.

Later, we'll add other information to the struct as it becomes
convenient.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12 20:14:55 -04:00
Linus Torvalds
8213a2f3ee Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull pile 2 of execve and kernel_thread unification work from Al Viro:
 "Stuff in there: kernel_thread/kernel_execve/sys_execve conversions for
  several more architectures plus assorted signal fixes and cleanups.

  There'll be more (in particular, real fixes for the alpha
  do_notify_resume() irq mess)..."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (43 commits)
  alpha: don't open-code trace_report_syscall_{enter,exit}
  Uninclude linux/freezer.h
  m32r: trim masks
  avr32: trim masks
  tile: don't bother with SIGTRAP in setup_frame
  microblaze: don't bother with SIGTRAP in setup_rt_frame()
  mn10300: don't bother with SIGTRAP in setup_frame()
  frv: no need to raise SIGTRAP in setup_frame()
  x86: get rid of duplicate code in case of CONFIG_VM86
  unicore32: remove pointless test
  h8300: trim _TIF_WORK_MASK
  parisc: decide whether to go to slow path (tracesys) based on thread flags
  parisc: don't bother looping in do_signal()
  parisc: fix double restarts
  bury the rest of TIF_IRET
  sanitize tsk_is_polling()
  bury _TIF_RESTORE_SIGMASK
  unicore32: unobfuscate _TIF_WORK_MASK
  mips: NOTIFY_RESUME is not needed in TIF masks
  mips: merge the identical "return from syscall" per-ABI code
  ...

Conflicts:
	arch/arm/include/asm/thread_info.h
2012-10-12 10:49:08 +09:00
Gong Tao
d23b5799b6 openrisc: mask interrupts in irq_mask_ack function
or1k_pic_mask_ack was failing to actually mask the IRQ.

Signed-off-by: Gong Tao <gongtao0607@gmail.com>
Signed-off-by: Jonas Bonn <jonas@southpole.se>
2012-10-11 11:27:26 +02:00
Jonas Bonn
8eea8a6a9a openrisc: fix typos in comments and warnings
Signed-off-by: Jonas Bonn <jonas@southpole.se>
2012-10-11 11:27:25 +02:00
Jonas Bonn
f248ef1cd3 openrisc: PIC should act on domain-local irqs
Now that IRQ domains are in use, we should be acting on domain-local
IRQ numbers (hwirq) instead of 'global' ones.

Signed-off-by: Jonas Bonn <jonas@southpole.se>
2012-10-11 11:27:25 +02:00
Vladimir Murzin
9b76beb071 openrisc: Make cpu_relax() invoke barrier()
Make cpu_relax() invoke barrier() to be the same as other arches.

Signed-off-by: Vladimir Murzin <murzin.v@gmail.com>
Signed-off-by: Jonas Bonn <jonas@southpole.se>
2012-10-11 11:27:19 +02:00
David Howells
913c230200 UAPI: (Scripted) Disintegrate arch/openrisc/include/asm
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
2012-10-09 09:47:18 +01:00
Linus Torvalds
9e2d8656f5 Merge branch 'akpm' (Andrew's patch-bomb)
Merge patches from Andrew Morton:
 "A few misc things and very nearly all of the MM tree.  A tremendous
  amount of stuff (again), including a significant rbtree library
  rework."

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (160 commits)
  sparc64: Support transparent huge pages.
  mm: thp: Use more portable PMD clearing sequenece in zap_huge_pmd().
  mm: Add and use update_mmu_cache_pmd() in transparent huge page code.
  sparc64: Document PGD and PMD layout.
  sparc64: Eliminate PTE table memory wastage.
  sparc64: Halve the size of PTE tables
  sparc64: Only support 4MB huge pages and 8KB base pages.
  memory-hotplug: suppress "Trying to free nonexistent resource <XXXXXXXXXXXXXXXX-YYYYYYYYYYYYYYYY>" warning
  mm: memcg: clean up mm_match_cgroup() signature
  mm: document PageHuge somewhat
  mm: use %pK for /proc/vmallocinfo
  mm, thp: fix mlock statistics
  mm, thp: fix mapped pages avoiding unevictable list on mlock
  memory-hotplug: update memory block's state and notify userspace
  memory-hotplug: preparation to notify memory block's state at memory hot remove
  mm: avoid section mismatch warning for memblock_type_name
  make GFP_NOTRACK definition unconditional
  cma: decrease cc.nr_migratepages after reclaiming pagelist
  CMA: migrate mlocked pages
  kpageflags: fix wrong KPF_THP on non-huge compound pages
  ...
2012-10-09 16:23:15 +09:00
Shaohua Li
45cac65b0f readahead: fault retry breaks mmap file read random detection
.fault now can retry.  The retry can break state machine of .fault.  In
filemap_fault, if page is miss, ra->mmap_miss is increased.  In the second
try, since the page is in page cache now, ra->mmap_miss is decreased.  And
these are done in one fault, so we can't detect random mmap file access.

Add a new flag to indicate .fault is tried once.  In the second try, skip
ra->mmap_miss decreasing.  The filemap_fault state machine is ok with it.

I only tested x86, didn't test other archs, but looks the change for other
archs is obvious, but who knows :)

Signed-off-by: Shaohua Li <shaohua.li@fusionio.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09 16:22:47 +09:00
Linus Torvalds
50e0d10232 This has three changes for asm-generic that did not really fit into any
other branch as normal asm-generic changes do. One is a fix for a
 build warning, the other two are more interesting:
 
 * A patch from Mark Brown to allow using the common clock infrastructure
 on all architectures, so we can use the clock API in architecture
 independent device drivers.
 
 * The UAPI split patches from David Howells for the asm-generic files.
 There are other architecture specific series that are going through
 the arch maintainer tree and that depend on this one.
 
 There may be a few small merge conflicts between Mark's patch and
 the following arch header file split patches. In each case the solution
 will be to keep the new "generic-y += clkdev.h" line, even if it
 ends up being the only line in the Kbuild file.
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Merge tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull asm-generic updates from Arnd Bergmann:
 "This has three changes for asm-generic that did not really fit into
  any other branch as normal asm-generic changes do.  One is a fix for a
  build warning, the other two are more interesting:

   * A patch from Mark Brown to allow using the common clock
     infrastructure on all architectures, so we can use the clock API in
     architecture independent device drivers.

   * The UAPI split patches from David Howells for the asm-generic
     files.  There are other architecture specific series that are going
     through the arch maintainer tree and that depend on this one.

  There may be a few small merge conflicts between Mark's patch and the
  following arch header file split patches.  In each case the solution
  will be to keep the new "generic-y += clkdev.h" line, even if it ends
  up being the only line in the Kbuild file."

* tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  UAPI: (Scripted) Disintegrate include/asm-generic
  asm-generic: Add default clkdev.h
  asm-generic: xor: mark static functions as __maybe_unused
2012-10-09 15:58:38 +09:00
Linus Torvalds
ed5062ddaa Merge branch 'uapi-prep' of git://git.infradead.org/users/dhowells/linux-headers
Pull UAPI disintegration fixes from David Howells:
 "There are three main parts:

 (1) I found I needed some more fixups in the wake of testing Arm64
     (some asm/unistd.h files had weird guards that caused problems -
     mostly in arches for which I don't have a compiler) and some
     __KERNEL__ splitting needed to take place in Arm64.

 (2) I found that c6x was missing some __KERNEL__ guards in its
     asm/signal.h.  Mark Salter pointed me at a tree with a patch to
     remove that file entirely and use the asm-generic variant instead.

 (3) Lastly, m68k turned out to have a header installation problem due
     to it lacking a kvm_para.h file.

     The conditional installation bits for linux/kvm_para.h, linux/kvm.h
     and linux/a.out.h weren't very well specified - and didn't work if
     an arch didn't have the asm/ version of that file, but there *was*
     an asm-generic/ version.

     It seems the "ifneq $((wildcard ...),)" for each of those three
     headers in include/kernel/Kbuild is invoked twice during header
     installation, and the second time it matches on the just installed
     asm-generic/kvm_para.h file and thus incorrectly installs
     linux/kvm_para.h as well.

     Most arches actually have an asm/kvm_para.h, so this wasn't
     detectable in those."

* 'uapi-prep' of git://git.infradead.org/users/dhowells/linux-headers:
  UAPI: Fix conditional header installation handling (notably kvm_para.h on m68k)
  c6x: remove c6x signal.h
  UAPI: Split compound conditionals containing __KERNEL__ in Arm64
  UAPI: Fix the guards on various asm/unistd.h files
  c6x: make dsk6455 the default config
2012-10-07 07:55:10 +09:00
Jiri Kosina
16f3e95b32 cross-arch: don't corrupt personality flags upon exec()
Historically, the top three bytes of personality have been used for
things such as ADDR_NO_RANDOMIZE, which made sense only for specific
architectures.

We now however have a flag there that is general no matter the
architecture (UNAME26); generally we have to be careful to preserve the
personality flags across exec().

This patch tries to fix all architectures that forcefully overwrite
personality flags during exec() (ppc32 and s390 have been fixed recently
by commits f9783ec862 ("[S390] Do not clobber personality flags on
exec") and 59e4c3a2fe ("powerpc/32: Don't clobber personality flags on
exec") in a similar way already).

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06 03:04:47 +09:00
Arnd Bergmann
c37d6154c0 Merge branch 'disintegrate-asm-generic' of git://git.infradead.org/users/dhowells/linux-headers into asm-generic
Patches from David Howells <dhowells@redhat.com>:

This is to complete part of the UAPI disintegration for which the
preparatory patches were pulled recently.

Note that there are some fixup patches which are at the base of the
branch aimed at you, plus all arches get the asm-generic branch merged in too.

* 'disintegrate-asm-generic' of git://git.infradead.org/users/dhowells/linux-headers:
  UAPI: (Scripted) Disintegrate include/asm-generic
  UAPI: Fix conditional header installation handling (notably kvm_para.h on m68k)
  c6x: remove c6x signal.h
  UAPI: Split compound conditionals containing __KERNEL__ in Arm64
  UAPI: Fix the guards on various asm/unistd.h files

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2012-10-04 22:57:51 +02:00
David Howells
890139529d UAPI: Fix the guards on various asm/unistd.h files
asm-generic/unistd.h and a number of asm/unistd.h files have been given
reinclusion guards that allow the guard to be overridden if __SYSCALL is
defined.  Unfortunately, these files define __SYSCALL and don't undefine it
when they've finished with it, thus rendering the guard ineffective.

The reason for this override is to allow the file to be #included multiple
times with different settings on __SYSCALL for purposes like generating syscall
tables.

The following guards are problematic:

arch/arm64/include/asm/unistd.h:#if !defined(__ASM_UNISTD_H) || defined(__SYSCALL)
arch/arm64/include/asm/unistd32.h:#if !defined(__ASM_UNISTD32_H) || defined(__SYSCALL)
arch/c6x/include/asm/unistd.h:#if !defined(_ASM_C6X_UNISTD_H) || defined(__SYSCALL)
arch/hexagon/include/asm/unistd.h:#if !defined(_ASM_HEXAGON_UNISTD_H) || defined(__SYSCALL)
arch/openrisc/include/asm/unistd.h:#if !defined(__ASM_OPENRISC_UNISTD_H) || defined(__SYSCALL)
arch/score/include/asm/unistd.h:#if !defined(_ASM_SCORE_UNISTD_H) || defined(__SYSCALL)
arch/tile/include/asm/unistd.h:#if !defined(_ASM_TILE_UNISTD_H) || defined(__SYSCALL)
arch/unicore32/include/asm/unistd.h:#if !defined(__UNICORE_UNISTD_H__) || defined(__SYSCALL)
include/asm-generic/unistd.h:#if !defined(_ASM_GENERIC_UNISTD_H) || defined(__SYSCALL)

On the assumption that the guards' ineffectiveness has passed unnoticed, just
remove these guards entirely.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2012-10-04 12:10:18 +01:00
Mark Brown
e7a570ff7d asm-generic: Add default clkdev.h
Ease the deployment of clkdev by providing a default asm/clkdev.h for
use if the arch does not have an include/asm/clkdev.h.

Due to limitations in Kbuild we manually add clkdev.h to all
architectures that don't have one rather than having the header appear
by default.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2012-10-03 21:33:53 +02:00
David Howells
4413e16d9d UAPI: (Scripted) Set up UAPI Kbuild files
Set up empty UAPI Kbuild files to be populated by the header splitter.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
2012-10-02 18:01:35 +01:00
Al Viro
16a8016372 sanitize tsk_is_polling()
Make default just return 0.  The current default (checking
TIF_POLLING_NRFLAG) is taken to architectures that need it;
ones that don't do polling in their idle threads don't need
to defined TIF_POLLING_NRFLAG at all.

ia64 defined both TS_POLLING (used by its tsk_is_polling())
and TIF_POLLING_NRFLAG (not used at all).  Killed the latter...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-01 09:58:13 -04:00
Al Viro
8af4efac26 bury _TIF_RESTORE_SIGMASK
never used...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-01 09:58:12 -04:00
David Howells
786d35d45c Make most arch asm/module.h files use asm-generic/module.h
Use the mapping of Elf_[SPE]hdr, Elf_Addr, Elf_Sym, Elf_Dyn, Elf_Rel/Rela,
ELF_R_TYPE() and ELF_R_SYM() to either the 32-bit version or the 64-bit version
into asm-generic/module.h for all arches bar MIPS.

Also, use the generic definition mod_arch_specific where possible.

To this end, I've defined three new config bools:

 (*) HAVE_MOD_ARCH_SPECIFIC

     Arches define this if they don't want to use the empty generic
     mod_arch_specific struct.

 (*) MODULES_USE_ELF_RELA

     Arches define this if their modules can contain RELA records.  This causes
     the Elf_Rela mapping to be emitted and allows apply_relocate_add() to be
     defined by the arch rather than have the core emit an error message.

 (*) MODULES_USE_ELF_REL

     Arches define this if their modules can contain REL records.  This causes
     the Elf_Rel mapping to be emitted and allows apply_relocate() to be
     defined by the arch rather than have the core emit an error message.

Note that it is possible to allow both REL and RELA records: m68k and mips are
two arches that do this.

With this, some arch asm/module.h files can be deleted entirely and replaced
with a generic-y marker in the arch Kbuild file.

Additionally, I have removed the bits from m32r and score that handle the
unsupported type of relocation record as that's now handled centrally.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 14:31:03 +09:30
Kees Cook
e2bebb4ae6 audit: define AUDIT_ARCH_OPENRISC
When using audit on OpenRISC, an audit arch is needed. This defines
it and fixes a compile-time bug uncovered in linux-next, likely from a
cut/paste from an arch with 64/32-bit modes that defined arch_arch():
arch/openrisc/kernel/ptrace.c:190:2: error: implicit declaration of function 'audit_arch'

This replaces it with the newly defined AUDIT_ARCH_OPENRISC, since it
is only 32-bit, and currently only operates in big-endian mode.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jonas Bonn <jonas@southpole.se>
2012-09-21 08:09:54 +02:00
Will Deacon
807607f79b openrisc: delay: fix handling of counter overflow
If the counter overflows during a __delay operation, we will exit the
loop prematurely. For example, calling __delay(0x100) with the counter
at 0xffffff00 gives us a target of 0x0. The unsigned comparison in the
while loop will likely be false on the first iteration (if the counter
is now anything other than 0) and we will return early.

This patch fixes the problem by comparing deltas in the loop rather than
absolute values.

Cc: Jon Masters <jcm@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jonas Bonn <jonas@southpole.se>
2012-09-01 16:36:14 +02:00
Will Deacon
439164663e openrisc: delay: fix loops calculation for __const_udelay
The openrisc implementation of __const_udelay casts the result of a
32-bit multiplication to 64 bits and passes the top 32 bits to __delay.
Since there are no casts on the arguments, this results in a __delay of
zero, regardless of the xloops parameter.

This patch fixes the problem by casting xloops to (unsigned long long),
ensuring that the multiplication is not truncated.

Cc: Jon Masters <jcm@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jonas Bonn <jonas@southpole.se>
2012-09-01 16:36:03 +02:00
Paul Bolle
459dac82b5 Remove useless wrappers of asm-generic/rmap.h
xtensa has a header (in its include/asm directory) that is a thin
wrapper around asm-generic/rmap.h. This wrapper is useless, since that
header doesn't exist. It is also unused (no file includes asm/rmap.h).

openrisc generates a similar header at build time (using a generic-y
entry in include/asm/Kbuild). This generated header is useless and
unused too.

Remove this header and this generic-y entry.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-06-28 11:29:26 +02:00
Paul Bolle
da870585b3 Remove useless wrappers of asm-generic/cpumask.h
frv and xtensa both have a header (in their include/asm directories)
that are thin wrappers around asm-generic/cpumask.h. These wrappers are
useless, since that header doesn't exist. They are also unused (all
files including asm/cpumask.h are x86 specific).

hexagon and openrisc generate similar headers at build time (using a
generic-y entry in include/asm/Kbuild). These generated headers are
useless and unused too.

Remove these headers and generic-y entries.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Richard Kuo <rkuo@codeaurora.org>
Acked-by: David Howells <dhowells@redhat.com> [FRV]
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-06-28 11:19:19 +02:00
Al Viro
efee984c27 new helper: signal_delivered()
Does block_sigmask() + tracehook_signal_handler();  called when
sigframe has been successfully built.  All architectures converted
to it; block_sigmask() itself is gone now (merged into this one).

I'm still not too happy with the signature, but that's a separate
story (IMO we need a structure that would contain signal number +
siginfo + k_sigaction, so that get_signal_to_deliver() would fill one,
signal_delivered(), handle_signal() and probably setup...frame() -
take one).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:52 -04:00
Al Viro
77097ae503 most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from set
Only 3 out of 63 do not.  Renamed the current variant to __set_current_blocked(),
added set_current_blocked() that will exclude unblockable signals, switched
open-coded instances to it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:51 -04:00
Al Viro
a610d6e672 pull clearing RESTORE_SIGMASK into block_sigmask()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:49 -04:00
Al Viro
39974d085d openrisc: tracehook_signal_handler() is supposed to be called on success
... not if sigframe couldn't have been built.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:48 -04:00
Al Viro
b7f9a11a6c new helper: sigmask_to_save()
replace boilerplate "should we use ->saved_sigmask or ->blocked?"
with calls of obvious inlined helper...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:48 -04:00
Al Viro
51a7b448d4 new helper: restore_saved_sigmask()
first fruits of ..._restore_sigmask() helpers: now we can take
boilerplate "signal didn't have a handler, clear RESTORE_SIGMASK
and restore the blocked mask from ->saved_mask" into a common
helper.  Open-coded instances switched...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:47 -04:00
Linus Torvalds
fb21affa49 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull second pile of signal handling patches from Al Viro:
 "This one is just task_work_add() series + remaining prereqs for it.

  There probably will be another pull request from that tree this
  cycle - at least for helpers, to get them out of the way for per-arch
  fixes remaining in the tree."

Fix trivial conflict in kernel/irq/manage.c: the merge of Andrew's pile
had brought in commit 97fd75b7b8 ("kernel/irq/manage.c: use the
pr_foo() infrastructure to prefix printks") which changed one of the
pr_err() calls that this merge moves around.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  keys: kill task_struct->replacement_session_keyring
  keys: kill the dummy key_replace_session_keyring()
  keys: change keyctl_session_to_parent() to use task_work_add()
  genirq: reimplement exit_irq_thread() hook via task_work_add()
  task_work_add: generic process-context callbacks
  avr32: missed _TIF_NOTIFY_RESUME on one of do_notify_resume callers
  parisc: need to check NOTIFY_RESUME when exiting from syscall
  move key_repace_session_keyring() into tracehook_notify_resume()
  TIF_NOTIFY_RESUME is defined on all targets now
2012-05-31 18:47:30 -07:00
Jonas Bonn
b48b2c3e50 openrisc: use generic strnlen_user() function
The generic version is both easier to support and more correct.

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-27 21:00:32 -07:00
Linus Torvalds
36126f8f2e word-at-a-time: make the interfaces truly generic
This changes the interfaces in <asm/word-at-a-time.h> to be a bit more
complicated, but a lot more generic.

In particular, it allows us to really do the operations efficiently on
both little-endian and big-endian machines, pretty much regardless of
machine details.  For example, if you can rely on a fast population
count instruction on your architecture, this will allow you to make your
optimized <asm/word-at-a-time.h> file with that.

NOTE! The "generic" version in include/asm-generic/word-at-a-time.h is
not truly generic, it actually only works on big-endian.  Why? Because
on little-endian the generic algorithms are wasteful, since you can
inevitably do better. The x86 implementation is an example of that.

(The only truly non-generic part of the asm-generic implementation is
the "find_zero()" function, and you could make a little-endian version
of it.  And if the Kbuild infrastructure allowed us to pick a particular
header file, that would be lovely)

The <asm/word-at-a-time.h> functions are as follows:

 - WORD_AT_A_TIME_CONSTANTS: specific constants that the algorithm
   uses.

 - has_zero(): take a word, and determine if it has a zero byte in it.
   It gets the word, the pointer to the constant pool, and a pointer to
   an intermediate "data" field it can set.

   This is the "quick-and-dirty" zero tester: it's what is run inside
   the hot loops.

 - "prep_zero_mask()": take the word, the data that has_zero() produced,
   and the constant pool, and generate an *exact* mask of which byte had
   the first zero.  This is run directly *outside* the loop, and allows
   the "has_zero()" function to answer the "is there a zero byte"
   question without necessarily getting exactly *which* byte is the
   first one to contain a zero.

   If you do multiple byte lookups concurrently (eg "hash_name()", which
   looks for both NUL and '/' bytes), after you've done the prep_zero_mask()
   phase, the result of those can be or'ed together to get the "either
   or" case.

 - The result from "prep_zero_mask()" can then be fed into "find_zero()"
   (to find the byte offset of the first byte that was zero) or into
   "zero_bytemask()" (to find the bytemask of the bytes preceding the
   zero byte).

   The existence of zero_bytemask() is optional, and is not necessary
   for the normal string routines.  But dentry name hashing needs it, so
   if you enable DENTRY_WORD_AT_A_TIME you need to expose it.

This changes the generic strncpy_from_user() function and the dentry
hashing functions to use these modified word-at-a-time interfaces.  This
gets us back to the optimized state of the x86 strncpy that we lost in
the previous commit when moving over to the generic version.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-26 11:33:40 -07:00