1. 21 4月, 2013 4 次提交
  2. 16 4月, 2013 2 次提交
    • S
      perf/x86: Fix offcore_rsp valid mask for SNB/IVB · f1923820
      Stephane Eranian 提交于
      The valid mask for both offcore_response_0 and
      offcore_response_1 was wrong for SNB/SNB-EP,
      IVB/IVB-EP. It was possible to write to
      reserved bit and cause a GP fault crashing
      the kernel.
      
      This patch fixes the problem by correctly marking the
      reserved bits in the valid mask for all the processors
      mentioned above.
      
      A distinction between desktop and server parts is introduced
      because bits 24-30 are only available on the server parts.
      
      This version of the  patch is just a rebase to perf/urgent tree
      and should apply to older kernels as well.
      Signed-off-by: NStephane Eranian <eranian@google.com>
      Cc: peterz@infradead.org
      Cc: jolsa@redhat.com
      Cc: gregkh@linuxfoundation.org
      Cc: security@kernel.org
      Cc: ak@linux.intel.com
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      f1923820
    • I
      Merge branch 'uprobes/core' of... · b5210b2a
      Ingo Molnar 提交于
      Merge branch 'uprobes/core' of git://git.kernel.org/pub/scm/linux/kernel/git/oleg/misc into perf/core
      
      Pull uprobes updates from Oleg Nesterov:
      
       - "uretprobes" - an optimization to uprobes, like kretprobes are an optimization
         to kprobes. "perf probe -x file sym%return" now works like kretprobes.
      
       - PowerPC fixes plus a couple of cleanups/optimizations in uprobes and trace_uprobes.
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      b5210b2a
  3. 15 4月, 2013 12 次提交
  4. 14 4月, 2013 3 次提交
    • N
      watchdog: Revert the AT91RM9200_WATCHDOG dependency · 09549cd0
      Nicolas Ferre 提交于
      Compiling the at91rm9200_wdt.c driver without at91rm9200
      support was leading to several errors:
      
      drivers/built-in.o: In function `at91_wdt_close':
      at91_adc.c:(.text+0xc9fe4): undefined reference to `at91_st_base'
      drivers/built-in.o: In function `at91_wdt_write':
      at91_adc.c:(.text+0xca004): undefined reference to `at91_st_base'
      drivers/built-in.o: In function `at91wdt_shutdown':
      at91_adc.c:(.text+0xca01c): undefined reference to `at91_st_base'
      drivers/built-in.o: In function `at91wdt_suspend':
      at91_adc.c:(.text+0xca038): undefined reference to `at91_st_base'
      drivers/built-in.o: In function `at91_wdt_open':
      at91_adc.c:(.text+0xca0cc): undefined reference to `at91_st_base'
      drivers/built-in.o:at91_adc.c:(.text+0xca2c8): more undefined references to
      `at91_st_base' follow
      
      So, reverting the modification of the "depends" Kconfig line
      introduced by patch a6a1bcd3 (watchdog: at91rm9200: add DT support)
      seems to be the good solution.
      Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
      Acked-by: NGuenter Roeck <linux@roeck-us.net>
      Signed-off-by: NWim Van Sebroeck <wim@iguana.be>
      09549cd0
    • S
      vfs: Revert spurious fix to spinning prevention in prune_icache_sb · 5b55d708
      Suleiman Souhlal 提交于
      Revert commit 62a3ddef ("vfs: fix spinning prevention in prune_icache_sb").
      
      This commit doesn't look right: since we are looking at the tail of the
      list (sb->s_inode_lru.prev) if we want to skip an inode, we should put
      it back at the head of the list instead of the tail, otherwise we will
      keep spinning on it.
      
      Discovered when investigating why prune_icache_sb came top in perf
      reports of a swapping load.
      Signed-off-by: NSuleiman Souhlal <suleiman@google.com>
      Signed-off-by: NHugh Dickins <hughd@google.com>
      Cc: stable@vger.kernel.org # v3.2+
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      5b55d708
    • L
      kobject: fix kset_find_obj() race with concurrent last kobject_put() · a49b7e82
      Linus Torvalds 提交于
      Anatol Pomozov identified a race condition that hits module unloading
      and re-loading.  To quote Anatol:
      
       "This is a race codition that exists between kset_find_obj() and
        kobject_put().  kset_find_obj() might return kobject that has refcount
        equal to 0 if this kobject is freeing by kobject_put() in other
        thread.
      
        Here is timeline for the crash in case if kset_find_obj() searches for
        an object tht nobody holds and other thread is doing kobject_put() on
        the same kobject:
      
          THREAD A (calls kset_find_obj())     THREAD B (calls kobject_put())
          splin_lock()
                                               atomic_dec_return(kobj->kref), counter gets zero here
                                               ... starts kobject cleanup ....
                                               spin_lock() // WAIT thread A in kobj_kset_leave()
          iterate over kset->list
          atomic_inc(kobj->kref) (counter becomes 1)
          spin_unlock()
                                               spin_lock() // taken
                                               // it does not know that thread A increased counter so it
                                               remove obj from list
                                               spin_unlock()
                                               vfree(module) // frees module object with containing kobj
      
          // kobj points to freed memory area!!
          kobject_put(kobj) // OOPS!!!!
      
        The race above happens because module.c tries to use kset_find_obj()
        when somebody unloads module.  The module.c code was introduced in
        commit 6494a93d"
      
      Anatol supplied a patch specific for module.c that worked around the
      problem by simply not using kset_find_obj() at all, but rather than make
      a local band-aid, this just fixes kset_find_obj() to be thread-safe
      using the proper model of refusing the get a new reference if the
      refcount has already dropped to zero.
      
      See examples of this proper refcount handling not only in the kref
      documentation, but in various other equivalent uses of this pattern by
      grepping for atomic_inc_not_zero().
      
      [ Side note: the module race does indicate that module loading and
        unloading is not properly serialized wrt sysfs information using the
        module mutex.  That may require further thought, but this is the
        correct fix at the kobject layer regardless. ]
      Reported-analyzed-and-tested-by: NAnatol Pomozov <anatol.pomozov@gmail.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: stable@vger.kernel.org
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a49b7e82
  5. 13 4月, 2013 19 次提交