1. 27 May, 2011 3 commits
  2. 26 May, 2011 1 commit
    • Frederic Weisbecker's avatar
      rcu: Fix unpaired rcu_irq_enter() from locking selftests · ba9f207c
      Frederic Weisbecker authored
      
      HARDIRQ_ENTER() maps to irq_enter() which calls rcu_irq_enter().
      But HARDIRQ_EXIT() maps to __irq_exit() which doesn't call
      rcu_irq_exit().
      
      So for every locking selftest that simulates hardirq disabled,
      we create an imbalance in the rcu extended quiescent state
      internal state.
      
      As a result, after the first missing rcu_irq_exit(), subsequent
      irqs won't exit dyntick-idle mode after leaving the interrupt
      handler.  This means that RCU won't see the affected CPU as being
      in an extended quiescent state, resulting in long grace-period
      delays (as in grace periods extending for hours).
      
      To fix this, just use __irq_enter() to simulate the hardirq
      context. This is sufficient for the locking selftests as we
      don't need to exit any extended quiescent state or perform
      any check that irqs normally do when they wake up from idle.
      
      As a side effect, this patch makes it possible to restore
      "rcu: Decrease memory-barrier usage based on semi-formal proof",
      which eventually helped finding this bug.
      Reported-and-tested-by: default avatarYinghai Lu <yinghai@kernel.org>
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Stable <stable@kernel.org>
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      ba9f207c
  3. 25 May, 2011 8 commits
  4. 19 May, 2011 4 commits
  5. 12 May, 2011 1 commit
    • Ingo Molnar's avatar
      vsprintf: Turn kptr_restrict off by default · 411f05f1
      Ingo Molnar authored
      
      kptr_restrict has been triggering bugs in apps such as perf, and it also makes
      the system less useful by default, so turn it off by default.
      
      This is how we generally handle security features that remove functionality,
      such as firewall code or SELinux - they have to be configured and activated
      from user-space.
      
      Distributions can turn kptr_restrict on again via this line in
      /etc/sysctrl.conf:
      
      kernel.kptr_restrict = 1
      
      ( Also mark the variable __read_mostly while at it, as it's typically modified
        only once per bootup, or not at all. )
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      411f05f1
  6. 06 May, 2011 2 commits
  7. 04 May, 2011 1 commit
  8. 02 May, 2011 1 commit
  9. 28 Apr, 2011 6 commits
  10. 25 Apr, 2011 1 commit
  11. 14 Apr, 2011 2 commits
  12. 10 Apr, 2011 1 commit
  13. 07 Apr, 2011 1 commit
  14. 06 Apr, 2011 1 commit
  15. 05 Apr, 2011 1 commit
  16. 31 Mar, 2011 1 commit
  17. 25 Mar, 2011 1 commit
  18. 24 Mar, 2011 4 commits
    • Namhyung Kim's avatar
      vsprintf: Introduce %pB format specifier · 0f77a8d3
      Namhyung Kim authored
      
      The %pB format specifier is for stack backtrace. Its handler
      sprint_backtrace() does symbol lookup using (address-1) to
      ensure the address will not point outside of the function.
      
      If there is a tail-call to the function marked "noreturn",
      gcc optimized out the code after the call then causes saved
      return address points outside of the function (i.e. the start
      of the next function), so pollutes call trace somewhat.
      
      This patch adds the %pB printk mechanism that allows architecture
      call-trace printout functions to improve backtrace printouts.
      Signed-off-by: default avatarNamhyung Kim <namhyung@gmail.com>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Acked-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: linux-arch@vger.kernel.org
      LKML-Reference: <1300934550-21394-1-git-send-email-namhyung@gmail.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      0f77a8d3
    • Akinobu Mita's avatar
      bitops: introduce CONFIG_GENERIC_FIND_BIT_LE · 0664996b
      Akinobu Mita authored
      
      This introduces CONFIG_GENERIC_FIND_BIT_LE to tell whether to use generic
      implementation of find_*_bit_le() in lib/find_next_bit.c or not.
      
      For now we select CONFIG_GENERIC_FIND_BIT_LE for all architectures which
      enable CONFIG_GENERIC_FIND_NEXT_BIT.
      
      But m68knommu wants to define own faster find_next_zero_bit_le() and
      continues using generic find_next_{,zero_}bit().
      (CONFIG_GENERIC_FIND_NEXT_BIT and !CONFIG_GENERIC_FIND_BIT_LE)
      Signed-off-by: default avatarAkinobu Mita <akinobu.mita@gmail.com>
      Cc: Greg Ungerer <gerg@uclinux.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      0664996b
    • Akinobu Mita's avatar
      asm-generic: change little-endian bitops to take any pointer types · a56560b3
      Akinobu Mita authored
      
      This makes the little-endian bitops take any pointer types by changing the
      prototypes and adding casts in the preprocessor macros.
      
      That would seem to at least make all the filesystem code happier, and they
      can continue to do just something like
      
        #define ext2_set_bit __test_and_set_bit_le
      
      (or whatever the exact sequence ends up being).
      Signed-off-by: default avatarAkinobu Mita <akinobu.mita@gmail.com>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Cc: Mikael Starvik <starvik@axis.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Cc: "Luck, Tony" <tony.luck@intel.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Kyle McMartin <kyle@mcmartin.ca>
      Cc: Matthew Wilcox <willy@debian.org>
      Cc: Grant Grundler <grundler@parisc-linux.org>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
      Cc: Hirokazu Takata <takata@linux-m32r.org>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Chris Zankel <chris@zankel.net>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      a56560b3
    • Akinobu Mita's avatar
      asm-generic: rename generic little-endian bitops functions · c4945b9e
      Akinobu Mita authored
      
      As a preparation for providing little-endian bitops for all architectures,
      This renames generic implementation of little-endian bitops.  (remove
      "generic_" prefix and postfix "_le")
      
      s/generic_find_next_le_bit/find_next_bit_le/
      s/generic_find_next_zero_le_bit/find_next_zero_bit_le/
      s/generic_find_first_zero_le_bit/find_first_zero_bit_le/
      s/generic___test_and_set_le_bit/__test_and_set_bit_le/
      s/generic___test_and_clear_le_bit/__test_and_clear_bit_le/
      s/generic_test_le_bit/test_bit_le/
      s/generic___set_le_bit/__set_bit_le/
      s/generic___clear_le_bit/__clear_bit_le/
      s/generic_test_and_set_le_bit/test_and_set_bit_le/
      s/generic_test_and_clear_le_bit/test_and_clear_bit_le/
      Signed-off-by: default avatarAkinobu Mita <akinobu.mita@gmail.com>
      Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
      Acked-by: default avatarHans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Roman Zippel <zippel@linux-m68k.org>
      Cc: Andreas Schwab <schwab@linux-m68k.org>
      Cc: Greg Ungerer <gerg@uclinux.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c4945b9e