1. 28 10月, 2010 3 次提交
  2. 26 10月, 2010 1 次提交
    • D
      MN10300: Fix the PERCPU() alignment to allow for workqueues · 52605627
      David Howells 提交于
      In the MN10300 arch, we occasionally see an assertion being tripped in
      alloc_cwqs() at the following line:
      
              /* just in case, make sure it's actually aligned */
        --->  BUG_ON(!IS_ALIGNED(wq->cpu_wq.v, align));
              return wq->cpu_wq.v ? 0 : -ENOMEM;
      
      The values are:
      
              wa->cpu_wq.v => 0x902776e0
              align => 0x100
      
      and align is calculated by the following:
      
              const size_t align = max_t(size_t, 1 << WORK_STRUCT_FLAG_BITS,
                                         __alignof__(unsigned long long));
      
      This is because the pointer in question (wq->cpu_wq.v) loses some of its
      lower bits to control flags, and so the object it points to must be
      sufficiently aligned to avoid the need to use those bits for pointing to
      things.
      
      Currently, 4 control bits and 4 colour bits are used in normal
      circumstances, plus a debugging bit if debugging is set.  This requires
      the cpu_workqueue_struct struct to be at least 256 bytes aligned (or 512
      bytes aligned with debugging).
      
      PERCPU() alignment on MN13000, however, is only 32 bytes as set in
      vmlinux.lds.S.  So we set this to PAGE_SIZE (4096) to match most other
      arches and stick a comment in alloc_cwqs() for anyone else who triggers
      the assertion.
      Reported-by: NAkira Takeuchi <takeuchi.akr@jp.panasonic.com>
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NMark Salter <msalter@redhat.com>
      Cc: Tejun Heo <tj@kernel.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      52605627
  3. 07 10月, 2010 1 次提交
    • D
      Fix IRQ flag handling naming · df9ee292
      David Howells 提交于
      Fix the IRQ flag handling naming.  In linux/irqflags.h under one configuration,
      it maps:
      
      	local_irq_enable() -> raw_local_irq_enable()
      	local_irq_disable() -> raw_local_irq_disable()
      	local_irq_save() -> raw_local_irq_save()
      	...
      
      and under the other configuration, it maps:
      
      	raw_local_irq_enable() -> local_irq_enable()
      	raw_local_irq_disable() -> local_irq_disable()
      	raw_local_irq_save() -> local_irq_save()
      	...
      
      This is quite confusing.  There should be one set of names expected of the
      arch, and this should be wrapped to give another set of names that are expected
      by users of this facility.
      
      Change this to have the arch provide:
      
      	flags = arch_local_save_flags()
      	flags = arch_local_irq_save()
      	arch_local_irq_restore(flags)
      	arch_local_irq_disable()
      	arch_local_irq_enable()
      	arch_irqs_disabled_flags(flags)
      	arch_irqs_disabled()
      	arch_safe_halt()
      
      Then linux/irqflags.h wraps these to provide:
      
      	raw_local_save_flags(flags)
      	raw_local_irq_save(flags)
      	raw_local_irq_restore(flags)
      	raw_local_irq_disable()
      	raw_local_irq_enable()
      	raw_irqs_disabled_flags(flags)
      	raw_irqs_disabled()
      	raw_safe_halt()
      
      with type checking on the flags 'arguments', and then wraps those to provide:
      
      	local_save_flags(flags)
      	local_irq_save(flags)
      	local_irq_restore(flags)
      	local_irq_disable()
      	local_irq_enable()
      	irqs_disabled_flags(flags)
      	irqs_disabled()
      	safe_halt()
      
      with tracing included if enabled.
      
      The arch functions can now all be inline functions rather than some of them
      having to be macros.
      
      Signed-off-by: David Howells <dhowells@redhat.com> [X86, FRV, MN10300]
      Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> [Tile]
      Signed-off-by: Michal Simek <monstr@monstr.eu> [Microblaze]
      Tested-by: Catalin Marinas <catalin.marinas@arm.com> [ARM]
      Acked-by: NThomas Gleixner <tglx@linutronix.de>
      Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> [AVR]
      Acked-by: Tony Luck <tony.luck@intel.com> [IA-64]
      Acked-by: Hirokazu Takata <takata@linux-m32r.org> [M32R]
      Acked-by: Greg Ungerer <gerg@uclinux.org> [M68K/M68KNOMMU]
      Acked-by: Ralf Baechle <ralf@linux-mips.org> [MIPS]
      Acked-by: Kyle McMartin <kyle@mcmartin.ca> [PA-RISC]
      Acked-by: Paul Mackerras <paulus@samba.org> [PowerPC]
      Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [S390]
      Acked-by: Chen Liqin <liqin.chen@sunplusct.com> [Score]
      Acked-by: Matt Fleming <matt@console-pimps.org> [SH]
      Acked-by: David S. Miller <davem@davemloft.net> [Sparc]
      Acked-by: Chris Zankel <chris@zankel.net> [Xtensa]
      Reviewed-by: Richard Henderson <rth@twiddle.net> [Alpha]
      Reviewed-by: Yoshinori Sato <ysato@users.sourceforge.jp> [H8300]
      Cc: starvik@axis.com [CRIS]
      Cc: jesper.nilsson@axis.com [CRIS]
      Cc: linux-cris-kernel@axis.com
      df9ee292
  4. 06 10月, 2010 1 次提交
    • L
      modules: Fix module_bug_list list corruption race · 5336377d
      Linus Torvalds 提交于
      With all the recent module loading cleanups, we've minimized the code
      that sits under module_mutex, fixing various deadlocks and making it
      possible to do most of the module loading in parallel.
      
      However, that whole conversion totally missed the rather obscure code
      that adds a new module to the list for BUG() handling.  That code was
      doubly obscure because (a) the code itself lives in lib/bugs.c (for
      dubious reasons) and (b) it gets called from the architecture-specific
      "module_finalize()" rather than from generic code.
      
      Calling it from arch-specific code makes no sense what-so-ever to begin
      with, and is now actively wrong since that code isn't protected by the
      module loading lock any more.
      
      So this commit moves the "module_bug_{finalize,cleanup}()" calls away
      from the arch-specific code, and into the generic code - and in the
      process protects it with the module_mutex so that the list operations
      are now safe.
      
      Future fixups:
       - move the module list handling code into kernel/module.c where it
         belongs.
       - get rid of 'module_bug_list' and just use the regular list of modules
         (called 'modules' - imagine that) that we already create and maintain
         for other reasons.
      Reported-and-tested-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: Adrian Bunk <bunk@kernel.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: stable@kernel.org
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      5336377d
  5. 28 9月, 2010 5 次提交
  6. 15 9月, 2010 1 次提交
  7. 18 8月, 2010 1 次提交
    • D
      Make do_execve() take a const filename pointer · d7627467
      David Howells 提交于
      Make do_execve() take a const filename pointer so that kernel_execve() compiles
      correctly on ARM:
      
      arch/arm/kernel/sys_arm.c:88: warning: passing argument 1 of 'do_execve' discards qualifiers from pointer target type
      
      This also requires the argv and envp arguments to be consted twice, once for
      the pointer array and once for the strings the array points to.  This is
      because do_execve() passes a pointer to the filename (now const) to
      copy_strings_kernel().  A simpler alternative would be to cast the filename
      pointer in do_execve() when it's passed to copy_strings_kernel().
      
      do_execve() may not change any of the strings it is passed as part of the argv
      or envp lists as they are some of them in .rodata, so marking these strings as
      const should be fine.
      
      Further kernel_execve() and sys_execve() need to be changed to match.
      
      This has been test built on x86_64, frv, arm and mips.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Tested-by: NRalf Baechle <ralf@linux-mips.org>
      Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      d7627467
  8. 14 8月, 2010 1 次提交
  9. 13 8月, 2010 2 次提交
  10. 30 3月, 2010 1 次提交
    • T
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo 提交于
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
      
      percpu.h is included by sched.h and module.h and thus ends up being
      included when building most .c files.  percpu.h includes slab.h which
      in turn includes gfp.h making everything defined by the two files
      universally available and complicating inclusion dependencies.
      
      percpu.h -> slab.h dependency is about to be removed.  Prepare for
      this change by updating users of gfp and slab facilities include those
      headers directly instead of assuming availability.  As this conversion
      needs to touch large number of source files, the following script is
      used as the basis of conversion.
      
        http://userweb.kernel.org/~tj/misc/slabh-sweep.py
      
      The script does the followings.
      
      * Scan files for gfp and slab usages and update includes such that
        only the necessary includes are there.  ie. if only gfp is used,
        gfp.h, if slab is used, slab.h.
      
      * When the script inserts a new include, it looks at the include
        blocks and try to put the new include such that its order conforms
        to its surrounding.  It's put in the include block which contains
        core kernel includes, in the same order that the rest are ordered -
        alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
        doesn't seem to be any matching order.
      
      * If the script can't find a place to put a new include (mostly
        because the file doesn't have fitting include block), it prints out
        an error message indicating which .h file needs to be added to the
        file.
      
      The conversion was done in the following steps.
      
      1. The initial automatic conversion of all .c files updated slightly
         over 4000 files, deleting around 700 includes and adding ~480 gfp.h
         and ~3000 slab.h inclusions.  The script emitted errors for ~400
         files.
      
      2. Each error was manually checked.  Some didn't need the inclusion,
         some needed manual addition while adding it to implementation .h or
         embedding .c file was more appropriate for others.  This step added
         inclusions to around 150 files.
      
      3. The script was run again and the output was compared to the edits
         from #2 to make sure no file was left behind.
      
      4. Several build tests were done and a couple of problems were fixed.
         e.g. lib/decompress_*.c used malloc/free() wrappers around slab
         APIs requiring slab.h to be added manually.
      
      5. The script was run on all .h files but without automatically
         editing them as sprinkling gfp.h and slab.h inclusions around .h
         files could easily lead to inclusion dependency hell.  Most gfp.h
         inclusion directives were ignored as stuff from gfp.h was usually
         wildly available and often used in preprocessor macros.  Each
         slab.h inclusion directive was examined and added manually as
         necessary.
      
      6. percpu.h was updated not to include slab.h.
      
      7. Build test were done on the following configurations and failures
         were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
         distributed build env didn't work with gcov compiles) and a few
         more options had to be turned off depending on archs to make things
         build (like ipr on powerpc/64 which failed due to missing writeq).
      
         * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
         * powerpc and powerpc64 SMP allmodconfig
         * sparc and sparc64 SMP allmodconfig
         * ia64 SMP allmodconfig
         * s390 SMP allmodconfig
         * alpha SMP allmodconfig
         * um on x86_64 SMP allmodconfig
      
      8. percpu.h modifications were reverted so that it could be applied as
         a separate patch and serve as bisection point.
      
      Given the fact that I had only a couple of failures from tests on step
      6, I'm fairly confident about the coverage of this conversion patch.
      If there is a breakage, it's likely to be something in one of the arch
      headers which should be easily discoverable easily on most builds of
      the specific arch.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  11. 13 3月, 2010 3 次提交
    • J
      mn10300: Convert mn10300 to use read/update_persistent_clock · f7a56575
      John Stultz 提交于
      This patch converts the mn10300 architecture to use the generic
      read_persistent_clock and update_persistent_clock interfaces, reducing
      the amount of arch specific code we have to maintain, and allowing for
      further cleanups in the future.
      
      I have not built or tested this patch, so help from arch maintainers
      would be appreciated.
      Signed-off-by: NJohn Stultz <johnstul@us.ibm.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      LKML-Reference: <1267675049-12337-3-git-send-email-johnstul@us.ibm.com>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      f7a56575
    • C
      Add generic sys_ipc wrapper · baed7fc9
      Christoph Hellwig 提交于
      Add a generic implementation of the ipc demultiplexer syscall.  Except for
      s390 and sparc64 all implementations of the sys_ipc are nearly identical.
      
      There are slight differences in the types of the parameters, where mips
      and powerpc as the only 64-bit architectures with sys_ipc use unsigned
      long for the "third" argument as it gets casted to a pointer later, while
      it traditionally is an "int" like most other paramters.  frv goes even
      further and uses unsigned long for all parameters execept for "ptr" which
      is a pointer type everywhere.  The change from int to unsigned long for
      "third" and back to "int" for the others on frv should be fine due to the
      in-register calling conventions for syscalls (we already had a similar
      issue with the generic sys_ptrace), but I'd prefer to have the arch
      maintainers looks over this in details.
      
      Except for that h8300, m68k and m68knommu lack an impplementation of the
      semtimedop sub call which this patch adds, and various architectures have
      gets used - at least on i386 it seems superflous as the compat code on
      x86-64 and ia64 doesn't even bother to implement it.
      
      [akpm@linux-foundation.org: add sys_ipc to sys_ni.c]
      Signed-off-by: NChristoph Hellwig <hch@lst.de>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: Jeff Dike <jdike@addtoit.com>
      Cc: Hirokazu Takata <takata@linux-m32r.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@elte.hu>
      Reviewed-by: NH. Peter Anvin <hpa@zytor.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: "Luck, Tony" <tony.luck@intel.com>
      Cc: James Morris <jmorris@namei.org>
      Cc: Andreas Schwab <schwab@linux-m68k.org>
      Acked-by: NJesper Nilsson <jesper.nilsson@axis.com>
      Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      Acked-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NKyle McMartin <kyle@mcmartin.ca>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      baed7fc9
    • C
      Add generic sys_old_select() · 5d0e5283
      Christoph Hellwig 提交于
      Add a generic implementation of the old select() syscall, which expects
      its argument in a memory block and switch all architectures over to use
      it.
      Signed-off-by: NChristoph Hellwig <hch@lst.de>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: Jeff Dike <jdike@addtoit.com>
      Cc: Hirokazu Takata <takata@linux-m32r.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@elte.hu>
      Reviewed-by: NH. Peter Anvin <hpa@zytor.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: "Luck, Tony" <tony.luck@intel.com>
      Cc: James Morris <jmorris@namei.org>
      Acked-by: NAndreas Schwab <schwab@linux-m68k.org>
      Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      Acked-by: NGreg Ungerer <gerg@uclinux.org>
      Acked-by: NDavid Howells <dhowells@redhat.com>
      Cc: Andreas Schwab <schwab@linux-m68k.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      5d0e5283
  12. 12 1月, 2010 3 次提交
  13. 15 12月, 2009 1 次提交
  14. 11 12月, 2009 2 次提交
  15. 29 10月, 2009 1 次提交
    • T
      percpu: make misc percpu symbols unique · 390dfd95
      Tejun Heo 提交于
      This patch updates misc percpu related symbols such that percpu
      symbols are unique and don't clash with local symbols.  This serves
      two purposes of decreasing the possibility of global percpu symbol
      collision and allowing dropping per_cpu__ prefix from percpu symbols.
      
      * drivers/crypto/padlock-aes.c: s/last_cword/paes_last_cword/
      
      * drivers/lguest/x86/core.c: s/last_cpu/lg_last_cpu/
      
      * drivers/s390/net/netiucv.c: rename the variable used in a macro to
        avoid clashing with percpu symbol
      
      * arch/mn10300/kernel/kprobes.c: replace current_ prefix with cur_ for
        static variables.  Please note that percpu symbol current_kprobe
        can't be changed as it's used by generic code.
      
      Partly based on Rusty Russell's "alloc_percpu: rename percpu vars
      which cause name clashes" patch.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Reviewed-by: NChristoph Lameter <cl@linux-foundation.org>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: Herbert Xu <herbert@gondor.apana.org.au>
      Cc: Chuck Ebbert <cebbert@redhat.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Masami Hiramatsu <mhiramat@redhat.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: linux390@de.ibm.com
      390dfd95
  16. 14 10月, 2009 1 次提交
  17. 25 9月, 2009 1 次提交
  18. 24 9月, 2009 2 次提交
  19. 23 9月, 2009 1 次提交
  20. 21 9月, 2009 2 次提交
    • I
      perf: Do the big rename: Performance Counters -> Performance Events · cdd6c482
      Ingo Molnar 提交于
      Bye-bye Performance Counters, welcome Performance Events!
      
      In the past few months the perfcounters subsystem has grown out its
      initial role of counting hardware events, and has become (and is
      becoming) a much broader generic event enumeration, reporting, logging,
      monitoring, analysis facility.
      
      Naming its core object 'perf_counter' and naming the subsystem
      'perfcounters' has become more and more of a misnomer. With pending
      code like hw-breakpoints support the 'counter' name is less and
      less appropriate.
      
      All in one, we've decided to rename the subsystem to 'performance
      events' and to propagate this rename through all fields, variables
      and API names. (in an ABI compatible fashion)
      
      The word 'event' is also a bit shorter than 'counter' - which makes
      it slightly more convenient to write/handle as well.
      
      Thanks goes to Stephane Eranian who first observed this misnomer and
      suggested a rename.
      
      User-space tooling and ABI compatibility is not affected - this patch
      should be function-invariant. (Also, defconfigs were not touched to
      keep the size down.)
      
      This patch has been generated via the following script:
      
        FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')
      
        sed -i \
          -e 's/PERF_EVENT_/PERF_RECORD_/g' \
          -e 's/PERF_COUNTER/PERF_EVENT/g' \
          -e 's/perf_counter/perf_event/g' \
          -e 's/nb_counters/nb_events/g' \
          -e 's/swcounter/swevent/g' \
          -e 's/tpcounter_event/tp_event/g' \
          $FILES
      
        for N in $(find . -name perf_counter.[ch]); do
          M=$(echo $N | sed 's/perf_counter/perf_event/g')
          mv $N $M
        done
      
        FILES=$(find . -name perf_event.*)
      
        sed -i \
          -e 's/COUNTER_MASK/REG_MASK/g' \
          -e 's/COUNTER/EVENT/g' \
          -e 's/\<event\>/event_id/g' \
          -e 's/counter/event/g' \
          -e 's/Counter/Event/g' \
          $FILES
      
      ... to keep it as correct as possible. This script can also be
      used by anyone who has pending perfcounters patches - it converts
      a Linux kernel tree over to the new naming. We tried to time this
      change to the point in time where the amount of pending patches
      is the smallest: the end of the merge window.
      
      Namespace clashes were fixed up in a preparatory patch - and some
      stylistic fallout will be fixed up in a subsequent patch.
      
      ( NOTE: 'counters' are still the proper terminology when we deal
        with hardware registers - and these sed scripts are a bit
        over-eager in renaming them. I've undone some of that, but
        in case there's something left where 'counter' would be
        better than 'event' we can undo that on an individual basis
        instead of touching an otherwise nicely automated patch. )
      Suggested-by: NStephane Eranian <eranian@google.com>
      Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Acked-by: NPaul Mackerras <paulus@samba.org>
      Reviewed-by: NArjan van de Ven <arjan@linux.intel.com>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Kyle McMartin <kyle@mcmartin.ca>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: <linux-arch@vger.kernel.org>
      LKML-Reference: <new-submission>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      cdd6c482
    • J
      d200c922
  21. 20 9月, 2009 1 次提交
  22. 02 9月, 2009 1 次提交
    • D
      KEYS: Add a keyctl to install a process's session keyring on its parent [try #6] · ee18d64c
      David Howells 提交于
      Add a keyctl to install a process's session keyring onto its parent.  This
      replaces the parent's session keyring.  Because the COW credential code does
      not permit one process to change another process's credentials directly, the
      change is deferred until userspace next starts executing again.  Normally this
      will be after a wait*() syscall.
      
      To support this, three new security hooks have been provided:
      cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in
      the blank security creds and key_session_to_parent() - which asks the LSM if
      the process may replace its parent's session keyring.
      
      The replacement may only happen if the process has the same ownership details
      as its parent, and the process has LINK permission on the session keyring, and
      the session keyring is owned by the process, and the LSM permits it.
      
      Note that this requires alteration to each architecture's notify_resume path.
      This has been done for all arches barring blackfin, m68k* and xtensa, all of
      which need assembly alteration to support TIF_NOTIFY_RESUME.  This allows the
      replacement to be performed at the point the parent process resumes userspace
      execution.
      
      This allows the userspace AFS pioctl emulation to fully emulate newpag() and
      the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to
      alter the parent process's PAG membership.  However, since kAFS doesn't use
      PAGs per se, but rather dumps the keys into the session keyring, the session
      keyring of the parent must be replaced if, for example, VIOCSETTOK is passed
      the newpag flag.
      
      This can be tested with the following program:
      
      	#include <stdio.h>
      	#include <stdlib.h>
      	#include <keyutils.h>
      
      	#define KEYCTL_SESSION_TO_PARENT	18
      
      	#define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0)
      
      	int main(int argc, char **argv)
      	{
      		key_serial_t keyring, key;
      		long ret;
      
      		keyring = keyctl_join_session_keyring(argv[1]);
      		OSERROR(keyring, "keyctl_join_session_keyring");
      
      		key = add_key("user", "a", "b", 1, keyring);
      		OSERROR(key, "add_key");
      
      		ret = keyctl(KEYCTL_SESSION_TO_PARENT);
      		OSERROR(ret, "KEYCTL_SESSION_TO_PARENT");
      
      		return 0;
      	}
      
      Compiled and linked with -lkeyutils, you should see something like:
      
      	[dhowells@andromeda ~]$ keyctl show
      	Session Keyring
      	       -3 --alswrv   4043  4043  keyring: _ses
      	355907932 --alswrv   4043    -1   \_ keyring: _uid.4043
      	[dhowells@andromeda ~]$ /tmp/newpag
      	[dhowells@andromeda ~]$ keyctl show
      	Session Keyring
      	       -3 --alswrv   4043  4043  keyring: _ses
      	1055658746 --alswrv   4043  4043   \_ user: a
      	[dhowells@andromeda ~]$ /tmp/newpag hello
      	[dhowells@andromeda ~]$ keyctl show
      	Session Keyring
      	       -3 --alswrv   4043  4043  keyring: hello
      	340417692 --alswrv   4043  4043   \_ user: a
      
      Where the test program creates a new session keyring, sticks a user key named
      'a' into it and then installs it on its parent.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      ee18d64c
  23. 18 7月, 2009 1 次提交
    • T
      vmlinux.lds.h: restructure BSS linker script macros · 04e448d9
      Tim Abbott 提交于
      The BSS section macros in vmlinux.lds.h currently place the .sbss
      input section outside the bounds of [__bss_start, __bss_end].  On all
      architectures except for microblaze that handle both .sbss and
      __bss_start/__bss_end, this is wrong: the .sbss input section is
      within the range [__bss_start, __bss_end].  Relatedly, the example
      code at the top of the file actually has __bss_start/__bss_end defined
      twice; I believe the right fix here is to define them in the
      BSS_SECTION macro but not in the BSS macro.
      
      Another problem with the current macros is that several
      architectures have an ALIGN(4) or some other small number just before
      __bss_stop in their linker scripts.  The BSS_SECTION macro currently
      hardcodes this to 4; while it should really be an argument.  It also
      ignores its sbss_align argument; fix that.
      
      mn10300 is the only user at present of any of the macros touched by
      this patch.  It looks like mn10300 actually was incorrectly converted
      to use the new BSS() macro (the alignment of 4 prior to conversion was
      a __bss_stop alignment, but the argument to the BSS macro is a start
      alignment).  So fix this as well.
      
      I'd like acks from Sam and David on this one.  Also CCing Paul, since
      he has a patch from me which will need to be updated to use
      BSS_SECTION(0, PAGE_SIZE, 4) once this gets merged.
      Signed-off-by: NTim Abbott <tabbott@ksplice.com>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: David Howells <dhowells@redhat.com>
      Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
      04e448d9
  24. 14 7月, 2009 1 次提交
  25. 13 7月, 2009 1 次提交
  26. 09 7月, 2009 1 次提交
    • T
      linker script: unify usage of discard definition · 023bf6f1
      Tejun Heo 提交于
      Discarded sections in different archs share some commonality but have
      considerable differences.  This led to linker script for each arch
      implementing its own /DISCARD/ definition, which makes maintaining
      tedious and adding new entries error-prone.
      
      This patch makes all linker scripts to move discard definitions to the
      end of the linker script and use the common DISCARDS macro.  As ld
      uses the first matching section definition, archs can include default
      discarded sections by including them earlier in the linker script.
      
      ia64 is notable because it first throws away some ia64 specific
      subsections and then include the rest of the sections into the final
      image, so those sections must be discarded before the inclusion.
      
      defconfig compile tested for x86, x86-64, powerpc, powerpc64, ia64,
      alpha, sparc, sparc64 and s390.  Michal Simek tested microblaze.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Acked-by: NPaul Mundt <lethal@linux-sh.org>
      Acked-by: NMike Frysinger <vapier@gentoo.org>
      Tested-by: NMichal Simek <monstr@monstr.eu>
      Cc: linux-arch@vger.kernel.org
      Cc: Michal Simek <monstr@monstr.eu>
      Cc: microblaze-uclinux@itee.uq.edu.au
      Cc: Sam Ravnborg <sam@ravnborg.org>
      Cc: Tony Luck <tony.luck@intel.com>
      023bf6f1