Commit Graph

14690 Commits

Author SHA1 Message Date
Eric W. Biederman
6e6668845f kernel/pid.c: reenable interrupts when alloc_pid() fails because init has exited
We're forgetting to reenable local interrupts on an error path.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Reported-by: Josh Boyer <jwboyer@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-12 14:34:00 -08:00
Linus Torvalds
2a6f79e8c1 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Three small fixlets"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/debug: Fix format string for 32-bit platforms
  sched: Fix warning in kernel/sched/fair.c
  sched/rt: Use root_domain of rt_rq not current processor
2013-02-05 07:58:24 +11:00
Linus Torvalds
51c1abb95f Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Three fixlets and two small (and low risk) hw-enablement changes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Fix event group context move
  x86/perf: Add IvyBridge EP support
  perf/x86: Fix P6 driver section warning
  arch/x86/tools/insn_sanity.c: Identify source of messages
  perf/x86: Enable Intel Lincroft/Penwell/Cloverview Atom support
2013-02-05 07:57:09 +11:00
Linus Torvalds
5dc31b5767 Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull two small RCU fixlets from Ingo Molnar.

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rcu: Make rcu_nocb_poll an early_param instead of module_param
  rcu: Prevent soft-lockup complaints about no-CBs CPUs
2013-02-05 07:56:07 +11:00
Jiri Olsa
0231bb5336 perf: Fix event group context move
When we have group with mixed events (hw/sw) we want to end up
with group leader being in hw context. So if group leader is
initialy sw event, we move all the events under hw context.

The move is done for each event by removing it from its context
and adding it back into proper one. As a part of the removal the
event is automatically disabled, which is not what we want at
this stage of creating groups.

The fix is to initialize event state after removal from sw
context.

This fix resulted from the following discussion:

  http://thread.gmane.org/gmane.linux.kernel.perf.user/1144

Reported-by: Andreas Hollmann <hollmann@in.tum.de>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vince@deater.net>
Link: http://lkml.kernel.org/r/1359714225-4231-1-git-send-email-jolsa@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-02-03 12:01:29 +01:00
Linus Torvalds
bdb0ae6a76 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Peter Anvin:
 "This is a collection of miscellaneous fixes, the most important one is
  the fix for the Samsung laptop bricking issue (auto-blacklisting the
  samsung-laptop driver); the efi_enabled() changes you see below are
  prerequisites for that fix.

  The other issues fixed are booting on OLPC XO-1.5, an UV fix, NMI
  debugging, and requiring CAP_SYS_RAWIO for MSR references, just as
  with I/O port references."

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  samsung-laptop: Disable on EFI hardware
  efi: Make 'efi_enabled' a function to query EFI facilities
  smp: Fix SMP function call empty cpu mask race
  x86/msr: Add capabilities check
  x86/dma-debug: Bump PREALLOC_DMA_DEBUG_ENTRIES
  x86/olpc: Fix olpc-xo1-sci.c build errors
  arch/x86/platform/uv: Fix incorrect tlb flush all issue
  x86-64: Fix unwind annotations in recent NMI changes
  x86-32: Start out cr0 clean, disable paging before modifying cr3/4
2013-01-31 17:08:43 +11:00
Dave Airlie
ff0d05bf73 Revert "console: implement lockdep support for console_lock"
This reverts commit daee779718.

I'll requeue this after the console locking fixes, so lockdep
is useful again for people until fbcon is fixed.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-01-31 15:46:56 +11:00
Wang YanQing
f44310b98d smp: Fix SMP function call empty cpu mask race
I get the following warning every day with v3.7, once or
twice a day:

  [ 2235.186027] WARNING: at /mnt/sda7/kernel/linux/arch/x86/kernel/apic/ipi.c:109 default_send_IPI_mask_logical+0x2f/0xb8()

As explained by Linus as well:

 |
 | Once we've done the "list_add_rcu()" to add it to the
 | queue, we can have (another) IPI to the target CPU that can
 | now see it and clear the mask.
 |
 | So by the time we get to actually send the IPI, the mask might
 | have been cleared by another IPI.
 |

This patch also fixes a system hang problem, if the data->cpumask
gets cleared after passing this point:

        if (WARN_ONCE(!mask, "empty IPI mask"))
                return;

then the problem in commit 83d349f35e ("x86: don't send an IPI to
the empty set of CPU's") will happen again.

Signed-off-by: Wang YanQing <udknight@gmail.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Jan Beulich <jbeulich@suse.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: peterz@infradead.org
Cc: mina86@mina86.org
Cc: srivatsa.bhat@linux.vnet.ibm.com
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/20130126075357.GA3205@udknight
[ Tidied up the changelog and the comment in the code. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-01-28 11:21:57 +01:00
Arnd Bergmann
cff3c124a7 sched/debug: Fix format string for 32-bit platforms
The type returned from atomic64_t can be either unsigned
long or unsigned long long, depending on the architecture.
Using a cast to unsigned long long lets us use the same
format string for all architectures.

Without this patch, building with scheduler debugging
enabled results in:

  kernel/sched/debug.c: In function 'print_cfs_rq':
  kernel/sched/debug.c:225:2: warning: format '%ld' expects argument of type 'long int', but argument 4 has type 'long long int' [-Wformat]
  kernel/sched/debug.c:225:2: warning: format '%ld' expects argument of type 'long int', but argument 3 has type 'long long int' [-Wformat]

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Turner <pjt@google.com>
Cc: linux-arm-kernel@list.infradead.org
Link: http://lkml.kernel.org/r/1359123276-15833-7-git-send-email-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-01-25 15:23:15 +01:00
Arnd Bergmann
38dc3348e3 sched: Fix warning in kernel/sched/fair.c
a4c96ae319 "sched: Unthrottle rt runqueues in
__disable_runtime()" turned the unthrottle_offline_cfs_rqs
function into a static symbol, which now triggers a warning
about it being potentially unused:

  kernel/sched/fair.c:2055:13: warning: 'unthrottle_offline_cfs_rqs' defined but not used [-Wunused-function]

Marking it __maybe_unused shuts up the gcc warning and lets the
compiler safely drop the function body when it's not being used.

To reproduce, build the ARM bcm2835_defconfig.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Boonstoppel <pboonstoppel@nvidia.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Turner <pjt@google.com>
Cc: linux-arm-kernel@list.infradead.org
Link: http://lkml.kernel.org/r/1359123276-15833-6-git-send-email-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-01-25 15:23:14 +01:00
Shawn Bohrer
aa7f67304d sched/rt: Use root_domain of rt_rq not current processor
When the system has multiple domains do_sched_rt_period_timer()
can run on any CPU and may iterate over all rt_rq in
cpu_online_mask.  This means when balance_runtime() is run for a
given rt_rq that rt_rq may be in a different rd than the current
processor.  Thus if we use smp_processor_id() to get rd in
do_balance_runtime() we may borrow runtime from a rt_rq that is
not part of our rd.

This changes do_balance_runtime to get the rd from the passed in
rt_rq ensuring that we borrow runtime only from the correct rd
for the given rt_rq.

This fixes a BUG at kernel/sched/rt.c:687! in __disable_runtime
when we try reclaim runtime lent to other rt_rq but runtime has
been lent to a rt_rq in another rd.

Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Mike Galbraith <bitbucket@online.de>
Cc: peterz@infradead.org
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/1358186131-29494-1-git-send-email-sbohrer@rgmadvisors.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-01-25 08:20:47 +01:00
Ingo Molnar
d36b7b9643 Merge branch 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent
Pull RCU fixes from Paul E. McKenney.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-01-24 13:28:24 +01:00
Tejun Heo
f56c3196f2 async: fix __lowest_in_progress()
Commit 083b804c4d ("async: use workqueue for worker pool") made it
possible that async jobs are moved from pending to running out-of-order.
While pending async jobs will be queued and dispatched for execution in
the same order, nothing guarantees they'll enter "1) move self to the
running queue" of async_run_entry_fn() in the same order.

Before the conversion, async implemented its own worker pool.  An async
worker, upon being woken up, fetches the first item from the pending
list, which kept the executing lists sorted.  The conversion to
workqueue was done by adding work_struct to each async_entry and async
just schedules the work item.  The queueing and dispatching of such work
items are still in order but now each worker thread is associated with a
specific async_entry and moves that specific async_entry to the
executing list.  So, depending on which worker reaches that point
earlier, which is non-deterministic, we may end up moving an async_entry
with larger cookie before one with smaller one.

This broke __lowest_in_progress().  running->domain may not be properly
sorted and is not guaranteed to contain lower cookies than pending list
when not empty.  Fix it by ensuring sort-inserting to the running list
and always looking at both pending and running when trying to determine
the lowest cookie.

Over time, the async synchronization implementation became quite messy.
We better restructure it such that each async_entry is linked to two
lists - one global and one per domain - and not move it when execution
starts.  There's no reason to distinguish pending and running.  They
behave the same for synchronization purposes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-22 16:21:24 -08:00
Linus Torvalds
d26d45253b Kprobes now uses the function tracer if it can. That is, if a probe
is placed on a function mcount/nop location, and the arch supports it,
 instead of adding a breakpoint, kprobes will register a function callback
 as that is much more efficient.
 
 The function tracer requires to update modules before they run, and
 uses the module notifier to do so. But if something else in the module
 notifiers registers a kprobe at one of these locations, before ftrace
 can get to it, then the system could fail.
 
 The function tracer must be initialized early, otherwise module notifiers
 that probe will only work by chance.
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Merge tag 'trace-3.8-rc4-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull ftrace fix from Steven Rostedt:
 "Kprobes now uses the function tracer if it can.  That is, if a probe
  is placed on a function mcount/nop location, and the arch supports it,
  instead of adding a breakpoint, kprobes will register a function
  callback as that is much more efficient.

  The function tracer requires to update modules before they run, and
  uses the module notifier to do so.  But if something else in the
  module notifiers registers a kprobe at one of these locations, before
  ftrace can get to it, then the system could fail.

  The function tracer must be initialized early, otherwise module
  notifiers that probe will only work by chance."

* tag 'trace-3.8-rc4-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Be first to run code modification on modules
2013-01-22 10:30:49 -08:00
Oleg Nesterov
9067ac85d5 wake_up_process() should be never used to wakeup a TASK_STOPPED/TRACED task
wake_up_process() should never wakeup a TASK_STOPPED/TRACED task.
Change it to use TASK_NORMAL and add the WARN_ON().

TASK_ALL has no other users, probably can be killed.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-22 10:08:17 -08:00
Oleg Nesterov
9899d11f65 ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL
putreg() assumes that the tracee is not running and pt_regs_access() can
safely play with its stack.  However a killed tracee can return from
ptrace_stop() to the low-level asm code and do RESTORE_REST, this means
that debugger can actually read/modify the kernel stack until the tracee
does SAVE_REST again.

set_task_blockstep() can race with SIGKILL too and in some sense this
race is even worse, the very fact the tracee can be woken up breaks the
logic.

As Linus suggested we can clear TASK_WAKEKILL around the arch_ptrace()
call, this ensures that nobody can ever wakeup the tracee while the
debugger looks at it.  Not only this fixes the mentioned problems, we
can do some cleanups/simplifications in arch_ptrace() paths.

Probably ptrace_unfreeze_traced() needs more callers, for example it
makes sense to make the tracee killable for oom-killer before
access_process_vm().

While at it, add the comment into may_ptrace_stop() to explain why
ptrace_stop() still can't rely on SIGKILL and signal_pending_state().

Reported-by: Salman Qazi <sqazi@google.com>
Reported-by: Suleiman Souhlal <suleiman@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-22 10:08:00 -08:00
Oleg Nesterov
910ffdb18a ptrace: introduce signal_wake_up_state() and ptrace_signal_wake_up()
Cleanup and preparation for the next change.

signal_wake_up(resume => true) is overused. None of ptrace/jctl callers
actually want to wakeup a TASK_WAKEKILL task, but they can't specify the
necessary mask.

Turn signal_wake_up() into signal_wake_up_state(state), reintroduce
signal_wake_up() as a trivial helper, and add ptrace_signal_wake_up()
which adds __TASK_TRACED.

This way ptrace_signal_wake_up() can work "inside" ptrace_request()
even if the tracee doesn't have the TASK_WAKEKILL bit set.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-22 08:50:08 -08:00
Steven Rostedt
c1bf08ac26 ftrace: Be first to run code modification on modules
If some other kernel subsystem has a module notifier, and adds a kprobe
to a ftrace mcount point (now that kprobes work on ftrace points),
when the ftrace notifier runs it will fail and disable ftrace, as well
as kprobes that are attached to ftrace points.

Here's the error:

 WARNING: at kernel/trace/ftrace.c:1618 ftrace_bug+0x239/0x280()
 Hardware name: Bochs
 Modules linked in: fat(+) stap_56d28a51b3fe546293ca0700b10bcb29__8059(F) nfsv4 auth_rpcgss nfs dns_resolver fscache xt_nat iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack lockd sunrpc ppdev parport_pc parport microcode virtio_net i2c_piix4 drm_kms_helper ttm drm i2c_core [last unloaded: bid_shared]
 Pid: 8068, comm: modprobe Tainted: GF            3.7.0-0.rc8.git0.1.fc19.x86_64 #1
 Call Trace:
  [<ffffffff8105e70f>] warn_slowpath_common+0x7f/0xc0
  [<ffffffff81134106>] ? __probe_kernel_read+0x46/0x70
  [<ffffffffa0180000>] ? 0xffffffffa017ffff
  [<ffffffffa0180000>] ? 0xffffffffa017ffff
  [<ffffffff8105e76a>] warn_slowpath_null+0x1a/0x20
  [<ffffffff810fd189>] ftrace_bug+0x239/0x280
  [<ffffffff810fd626>] ftrace_process_locs+0x376/0x520
  [<ffffffff810fefb7>] ftrace_module_notify+0x47/0x50
  [<ffffffff8163912d>] notifier_call_chain+0x4d/0x70
  [<ffffffff810882f8>] __blocking_notifier_call_chain+0x58/0x80
  [<ffffffff81088336>] blocking_notifier_call_chain+0x16/0x20
  [<ffffffff810c2a23>] sys_init_module+0x73/0x220
  [<ffffffff8163d719>] system_call_fastpath+0x16/0x1b
 ---[ end trace 9ef46351e53bbf80 ]---
 ftrace failed to modify [<ffffffffa0180000>] init_once+0x0/0x20 [fat]
  actual: cc:bb:d2:4b:e1

A kprobe was added to the init_once() function in the fat module on load.
But this happened before ftrace could have touched the code. As ftrace
didn't run yet, the kprobe system had no idea it was a ftrace point and
simply added a breakpoint to the code (0xcc in the cc:bb:d2:4b:e1).

Then when ftrace went to modify the location from a call to mcount/fentry
into a nop, it didn't see a call op, but instead it saw the breakpoint op
and not knowing what to do with it, ftrace shut itself down.

The solution is to simply give the ftrace module notifier the max priority.
This should have been done regardless, as the core code ftrace modification
also happens very early on in boot up. This makes the module modification
closer to core modification.

Link: http://lkml.kernel.org/r/20130107140333.593683061@goodmis.org

Cc: stable@vger.kernel.org
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reported-by: Frank Ch. Eigler <fche@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-01-21 13:21:50 -05:00
Linus Torvalds
ee61abb322 module: fix missing module_mutex unlock
Commit 1fb9341ac3 ("module: put modules in list much earlier") moved
some of the module initialization code around, and in the process
changed the exit paths too.  But for the duplicate export symbol error
case the change made the ddebug_cleanup path jump to after the module
mutex unlock, even though it happens with the mutex held.

Rusty has some patches to split this function up into some helper
functions, hopefully the mess of complex goto targets will go away
eventually.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-20 20:22:58 -08:00
Linus Torvalds
226364766f Various minor fixes, but a slightly more complex one to fix the per-cpu overload
problem introduced recently by kvm id changes.
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module fixes and a virtio block fix from Rusty Russell:
 "Various minor fixes, but a slightly more complex one to fix the
  per-cpu overload problem introduced recently by kvm id changes."

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  module: put modules in list much earlier.
  module: add new state MODULE_STATE_UNFORMED.
  module: prevent warning when finit_module a 0 sized file
  virtio-blk: Don't free ida when disk is in use
2013-01-20 16:44:28 -08:00
Linus Torvalds
3a142ed962 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull misc syscall fixes from Al Viro:

 - compat syscall fixes (discussed back in December)

 - a couple of "make life easier for sigaltstack stuff by reducing
   inter-tree dependencies"

 - fix up compiler/asmlinkage calling convention disagreement of
   sys_clone()

 - misc

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  sys_clone() needs asmlinkage_protect
  make sure that /linuxrc has std{in,out,err}
  x32: fix sigtimedwait
  x32: fix waitid()
  switch compat_sys_wait4() and compat_sys_waitid() to COMPAT_SYSCALL_DEFINE
  switch compat_sys_sigaltstack() to COMPAT_SYSCALL_DEFINE
  CONFIG_GENERIC_SIGALTSTACK build breakage with asm-generic/syscalls.h
  Ensure that kernel_init_freeable() is not inlined into non __init code
2013-01-20 13:58:48 -08:00
Oleg Nesterov
edea0d03ee ia64: kill thread_matches(), unexport ptrace_check_attach()
The ia64 function "thread_matches()" has no users since commit
e868a55c2a ("[IA64] remove find_thread_for_addr()").  Remove it.

This allows us to make ptrace_check_attach() static to kernel/ptrace.c,
which is good since we'll need to change the semantics of it and fix up
all the callers.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-20 12:26:05 -08:00
Al Viro
b1e0318b8c sys_clone() needs asmlinkage_protect
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-01-19 22:13:34 -05:00
Tejun Heo
774a1221e8 module, async: async_synchronize_full() on module init iff async is used
If the default iosched is built as module, the kernel may deadlock
while trying to load the iosched module on device probe if the probing
was running off async.  This is because async_synchronize_full() at
the end of module init ends up waiting for the async job which
initiated the module loading.

 async A				modprobe

 1. finds a device
 2. registers the block device
 3. request_module(default iosched)
					4. modprobe in userland
					5. load and init module
					6. async_synchronize_full()

Async A waits for modprobe to finish in request_module() and modprobe
waits for async A to finish in async_synchronize_full().

Because there's no easy to track dependency once control goes out to
userland, implementing properly nested flushing is difficult.  For
now, make module init perform async_synchronize_full() iff module init
has queued async jobs as suggested by Linus.

This avoids the described deadlock because iosched module doesn't use
async and thus wouldn't invoke async_synchronize_full().  This is
hacky and incomplete.  It will deadlock if async module loading nests;
however, this works around the known problem case and seems to be the
best of bad options.

For more details, please refer to the following thread.

  http://thread.gmane.org/gmane.linux.kernel/1420814

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Alex Riesen <raa.lkml@gmail.com>
Tested-by: Ming Lei <ming.lei@canonical.com>
Tested-by: Alex Riesen <raa.lkml@gmail.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-16 09:05:33 -08:00
Linus Torvalds
406089d015 The clean up patch commit 0fb9656d "tracing: Make tracing_enabled be equal
to tracing_on" caused two regressions.
 
 1) The irqs off latency tracer no longer starts if tracing_on is off
   when the tracer is set, and then tracing_on is enabled. The tracing_on
   file needs the hook that tracing_enabled had to enable tracers if they
   request it (call the tracer's start() method).
 
 2) That commit had a separate change that really should have been a
   separate patch, but it must have been added accidently with the -a
   option of git commit. But as the change is still related to the commit
   it wasn't noticed in review. That change, changed the way blocking is
   done by the trace_pipe file with respect to the tracing_on settings.
   I've been told that this change breaks current userspace, and this
   specific change is being reverted.
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Merge tag 'trace-3.8-rc3-regression-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing regression fixes from Steven Rostedt:
 "The clean up patch commit 0fb9656d95 "tracing: Make tracing_enabled
  be equal to tracing_on" caused two regressions.

   1) The irqs off latency tracer no longer starts if tracing_on is off
      when the tracer is set, and then tracing_on is enabled.  The
      tracing_on file needs the hook that tracing_enabled had to enable
      tracers if they request it (call the tracer's start() method).

   2) That commit had a separate change that really should have been a
      separate patch, but it must have been added accidently with the -a
      option of git commit.  But as the change is still related to the
      commit it wasn't noticed in review.  That change, changed the way
      blocking is done by the trace_pipe file with respect to the
      tracing_on settings.  I've been told that this change breaks
      current userspace, and this specific change is being reverted."

* tag 'trace-3.8-rc3-regression-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix regression of trace_pipe
  tracing: Fix regression with irqsoff tracer and tracing_on file
2013-01-14 20:22:16 -08:00
Liu Bo
250bfd3d8e tracing: Fix regression of trace_pipe
Commit 0fb9656d "tracing: Make tracing_enabled be equal to tracing_on"
changes the behaviour of trace_pipe, ie. it makes trace_pipe return if
we've read something and tracing is enabled, and this means that we have
to 'cat trace_pipe' again and again while running tests.

IMO the right way is if tracing is enabled, we always block and wait for
ring buffer, or we may lose what we want since ring buffer's size is limited.

Link: http://lkml.kernel.org/r/1358132051-5410-1-git-send-email-bo.li.liu@oracle.com

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-01-14 13:13:32 -05:00
Rusty Russell
1fb9341ac3 module: put modules in list much earlier.
Prarit's excellent bug report:
> In recent Fedora releases (F17 & F18) some users have reported seeing
> messages similar to
>
> [   15.478160] kvm: Could not allocate 304 bytes percpu data
> [   15.478174] PERCPU: allocation failed, size=304 align=32, alloc from
> reserved chunk failed
>
> during system boot.  In some cases, users have also reported seeing this
> message along with a failed load of other modules.
>
> What is happening is systemd is loading an instance of the kvm module for
> each cpu found (see commit e9bda3b).  When the module load occurs the kernel
> currently allocates the modules percpu data area prior to checking to see
> if the module is already loaded or is in the process of being loaded.  If
> the module is already loaded, or finishes load, the module loading code
> releases the current instance's module's percpu data.

Now we have a new state MODULE_STATE_UNFORMED, we can insert the
module into the list (and thus guarantee its uniqueness) before we
allocate the per-cpu region.

Reported-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Tested-by: Prarit Bhargava <prarit@redhat.com>
2013-01-12 13:27:46 +10:30
Rusty Russell
0d21b0e347 module: add new state MODULE_STATE_UNFORMED.
You should never look at such a module, so it's excised from all paths
which traverse the modules list.

We add the state at the end, to avoid gratuitous ABI break (ksplice).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-01-12 13:27:05 +10:30
Andrew Morton
829199197a kernel/audit.c: avoid negative sleep durations
audit_log_start() performs the same jiffies comparison in two places.
If sufficient time has elapsed between the two comparisons, the second
one produces a negative sleep duration:

  schedule_timeout: wrong timeout value fffffffffffffff0
  Pid: 6606, comm: trinity-child1 Not tainted 3.8.0-rc1+ #43
  Call Trace:
    schedule_timeout+0x305/0x340
    audit_log_start+0x311/0x470
    audit_log_exit+0x4b/0xfb0
    __audit_syscall_exit+0x25f/0x2c0
    sysret_audit+0x17/0x21

Fix it by performing the comparison a single time.

Reported-by: Dave Jones <davej@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-11 14:54:56 -08:00
Kees Cook
0644ec0cc8 audit: catch possible NULL audit buffers
It's possible for audit_log_start() to return NULL.  Handle it in the
various callers.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Julien Tinnes <jln@google.com>
Cc: Will Drewry <wad@google.com>
Cc: Steve Grubb <sgrubb@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-11 14:54:55 -08:00
Kees Cook
7b9205bd77 audit: create explicit AUDIT_SECCOMP event type
The seccomp path was using AUDIT_ANOM_ABEND from when seccomp mode 1
could only kill a process.  While we still want to make sure an audit
record is forced on a kill, this should use a separate record type since
seccomp mode 2 introduces other behaviors.

In the case of "handled" behaviors (process wasn't killed), only emit a
record if the process is under inspection.  This change also fixes
userspace examination of seccomp audit events, since it was considered
malformed due to missing fields of the AUDIT_ANOM_ABEND event type.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Julien Tinnes <jln@google.com>
Acked-by: Will Drewry <wad@chromium.org>
Acked-by: Steve Grubb <sgrubb@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-11 14:54:55 -08:00
Jiri Kosina
1b963c81b1 lockdep, rwsem: provide down_write_nest_lock()
down_write_nest_lock() provides a means to annotate locking scenario
where an outer lock is guaranteed to serialize the order nested locks
are being acquired.

This is analogoue to already existing mutex_lock_nest_lock() and
spin_lock_nest_lock().

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mel Gorman <mel@csn.ul.ie>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-11 14:54:55 -08:00
Steven Rostedt
2df8f8a6a8 tracing: Fix regression with irqsoff tracer and tracing_on file
Commit 02404baf1b "tracing: Remove deprecated tracing_enabled file"
removed the tracing_enabled file as it never worked properly and
the tracing_on file should be used instead. But the tracing_on file
didn't call into the tracers start/stop routines like the
tracing_enabled file did. This caused trace-cmd to break when it
enabled the irqsoff tracer.

If you just did "echo irqsoff > current_tracer" then it would work
properly. But the tool trace-cmd disables tracing first by writing
"0" into the tracing_on file. Then it writes "irqsoff" into
current_tracer and then writes "1" into tracing_on. Unfortunately,
the above commit changed the irqsoff tracer to check the tracing_on
status instead of the tracing_enabled status. If it's disabled then
it does not start the tracer internals.

The problem is that writing "1" into tracing_on does not call the
tracers "start" routine like writing "1" into tracing_enabled did.
This makes the irqsoff tracer not start when using the trace-cmd
tool, and is a regression for userspace.

Simple fix is to have the tracing_on file call the tracers start()
method when being enabled (and the stop() method when disabled).

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-01-11 16:14:10 -05:00
Randy Dunlap
bfbbd96c51 audit: fix auditfilter.c kernel-doc warnings
Fix new kernel-doc warning in auditfilter.c:

  Warning(kernel/auditfilter.c:1157): Excess function parameter 'uid' description in 'audit_receive_filter'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Cc: linux-audit@redhat.com (subscribers-only)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-10 14:35:23 -08:00
Linus Torvalds
4ffd4ebf9d commit 7bcfaf54f5
"tracing: Add trace_options kernel command line parameter"
 
 in consolidating the code, it removed a necessary nul terminator.
 This causes writing to the trace_options file to break. Although,
 setting the options/<options> file to 1 or 0 still worked fine.
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Merge tag 'trace-3.8-rc2-regression-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing regression fix from Steven Rostedt:
 "A change that came in this merge window broke the writing to the
  trace_options file.  It causes garbage to be read during the compare
  of option names, and breaks setting options via the trace_options
  file, although options can still be set via the options/<option>
  files."

* tag 'trace-3.8-rc2-regression-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix regression of trace_options file setting
2013-01-10 09:03:16 -08:00
Steven Rostedt
a8dd2176a8 tracing: Fix regression of trace_options file setting
The latest change to allow trace options to be set on the command
line also broke the trace_options file.

The zeroing of the last byte of the option name that is echoed into
the trace_option file was removed with the consolidation of some
of the code. The compare between the option and what was written to
the trace_options file fails because the string holding the data
written doesn't terminate with a null character.

A zero needs to be added to the end of the string copied from
user space.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-01-09 20:54:17 -05:00
Paul Gortmaker
1b0048a44c rcu: Make rcu_nocb_poll an early_param instead of module_param
The as-documented rcu_nocb_poll will fail to enable this feature
for two reasons.  (1) there is an extra "s" in the documented
name which is not in the code, and (2) since it uses module_param,
it really is expecting a prefix, akin to "rcutree.fanout_leaf"
and the prefix isn't documented.

However, there are several reasons why we might not want to
simply fix the typo and add the prefix:

1) we'd end up with rcutree.rcu_nocb_poll, and rather probably make
a change to rcutree.nocb_poll

2) if we did #1, then the prefix wouldn't be consistent with the
rcu_nocbs=<cpumap> parameter (i.e. one with, one without prefix)

3) the use of module_param in a header file is less than desired,
since it isn't immediately obvious that it will get processed
via rcutree.c and get the prefix from that (although use of
module_param_named() could clarify that.)

4) the implied export of /sys/module/rcutree/parameters/rcu_nocb_poll
data to userspace via module_param() doesn't really buy us anything,
as it is read-only and we can tell if it is enabled already without
it, since there is a printk at early boot telling us so.

In light of all that, just change it from a module_param() to an
early_setup() call, and worry about adding it to /sys later on if
we decide to allow a dynamic setting of it.

Also change the variable to be tagged as read_mostly, since it
will only ever be fiddled with at most, once at boot.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-01-08 14:12:19 -08:00
Paul Gortmaker
353af9c9a8 rcu: Prevent soft-lockup complaints about no-CBs CPUs
The wait_event() at the head of the rcu_nocb_kthread() can result in
soft-lockup complaints if the CPU in question does not register RCU
callbacks for an extended period.  This commit therefore changes
the wait_event() to a wait_event_interruptible().

Reported-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-01-08 14:12:18 -08:00
Linus Torvalds
d0631c6e09 Merge branch 'akpm' (fixes from Andrew)
Merge emailed fixes from Andrew Morton:
 "Bunch of fixes:

   - delayed IPC updates.  I held back on this because of some possible
     outstanding bug reports, but they appear to have been addressed in
     later versions

   - A bunch of MAINTAINERS updates

   - Yet Another RTC driver.  I'd held this back while a couple of
     little issues were being worked out.

  I'm expecting an intrusive-but-simple patchset from Joe Perches which
  splits up printk.c into kernel/printk/*.  That will be a pig to
  maintain for two months so if it passes testing I'd like to get it
  upstream after a week or so."

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (35 commits)
  printk: fix incorrect length from print_time() when seconds > 99999
  drivers/rtc/rtc-vt8500.c: fix handling of data passed in struct rtc_time
  drivers/rtc/rtc-vt8500.c: correct handling of CR_24H bitfield
  rtc: add RTC driver for TPS6586x
  MAINTAINERS: fix drivers/staging/sm7xx/
  MAINTAINERS: remove include/linux/of_pwm.h
  MAINTAINERS: remove arch/*/lib/perf_event*.c
  MAINTAINERS: remove drivers/mmc/host/imxmmc.*
  MAINTAINERS: fix Documentation/mei/
  MAINTAINERS: remove arch/x86/platform/mrst/pmu.*
  MAINTAINERS: remove firmware/isci/
  MAINTAINERS: fix drivers/ieee802154/
  MAINTAINERS: fix .../plat-mxc/include/mach/imxfb.h
  MAINTAINERS: remove drivers/video/epson1355fb.c
  MAINTAINERS: fix drivers/media/usb/dvb-usb/cxusb*
  MAINTAINERS: adjust for UAPI
  MAINTAINERS: fix drivers/media/platform/atmel-isi.c
  MAINTAINERS: fix arch/arm/mach-at91/include/mach/at_hdmac.h
  MAINTAINERS: fix drivers/rtc/rtc-vt8500.c
  MAINTAINERS: remove arch/arm/plat-s5p/
  ...
2013-01-07 07:42:38 -08:00
Oleg Nesterov
0c4a842349 signals: set_current_blocked() can use __set_current_blocked()
Cleanup.  And I think we need more cleanups, in particular
__set_current_blocked() and sigprocmask() should die.  Nobody should
ever block SIGKILL or SIGSTOP.

 - Change set_current_blocked() to use __set_current_blocked()

 - Change sys_sigprocmask() to use set_current_blocked(), this way it
   should not worry about SIGKILL/SIGSTOP.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-05 19:34:54 -08:00
Oleg Nesterov
5ba53ff648 signals: sys_ssetmask() uses uninitialized newmask
Commit 77097ae503 ("most of set_current_blocked() callers want
SIGKILL/SIGSTOP removed from set") removed the initialization of newmask
by accident, causing ltp to complain like this:

  ssetmask01    1  TFAIL  :  sgetmask() failed: TEST_ERRNO=???(0): Success

Restore the proper initialization.

Reported-and-tested-by: CAI Qian <caiqian@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: stable@kernel.org	# v3.5+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-05 19:34:54 -08:00
Roland Dreier
35dac27ced printk: fix incorrect length from print_time() when seconds > 99999
print_prefix() passes a NULL buf to print_time() to get the length of
the time prefix; when printk times are enabled, the current code just
returns the constant 15, which matches the format "[%5lu.%06lu] " used
to print the time value.  However, this is obviously incorrect when the
whole seconds part of the time gets beyond 5 digits (100000 seconds is a
bit more than a day of uptime).

The simple fix is to use snprintf(NULL, 0, ...) to calculate the actual
length of the time prefix.  This could be micro-optimized but it seems
better to have simpler, more readable code here.

The bug leads to the syslog system call miscomputing which messages fit
into the userspace buffer.  If there are enough messages to fill
log_buf_len and some have a timestamp >= 100000, dmesg may fail with:

    # dmesg
    klogctl: Bad address

When this happens, strace shows that the failure is indeed EFAULT due to
the kernel mistakenly accessing past the end of dmesg's buffer, since
dmesg asks the kernel how big a buffer it needs, allocates a bit more,
and then gets an error when it asks the kernel to fill it:

    syslog(0xa, 0, 0)                       = 1048576
    mmap(NULL, 1052672, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa4d25d2000
    syslog(0x3, 0x7fa4d25d2010, 0x100008)   = -1 EFAULT (Bad address)

As far as I can see, the bug has been there as long as print_time(),
which comes from commit 084681d14e ("printk: flush continuation lines
immediately to console") in 3.5-rc5.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Cc: Sylvain Munaut <s.munaut@whatever-company.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-04 16:11:48 -08:00
Sasha Levin
52441fa8f2 module: prevent warning when finit_module a 0 sized file
If we try to finit_module on a file sized 0 bytes vmalloc will
scream and spit out a warning.

Since modules have to be bigger than 0 bytes anyways we can just
check that beforehand and avoid the warning.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-01-03 11:10:32 +10:30
Al Viro
b2ddedcd21 x32: fix sigtimedwait
It needs 64bit timespec.  As it is, we end up truncating the timeout
to whole seconds; usually it doesn't matter, but for having all
sub-second timeouts truncated to one jiffy is visibly wrong.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-26 01:15:03 -05:00
Al Viro
a566c28882 x32: fix waitid()
It needs 64bit rusage and 32bit siginfo.  glibc never calls it with
non-NULL rusage pointer, or we would've seen breakage already...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-26 01:15:03 -05:00
Al Viro
8d9807b109 switch compat_sys_wait4() and compat_sys_waitid() to COMPAT_SYSCALL_DEFINE
Strictly speaking, ppc64 needs it for C ABI compliance.  Realistically
I would be very surprised if e.g. passing 0xffffffff as 'options'
argument to waitid() from 32bit task would cause problems, but yes,
it puts us into undefined behaviour territory.  ppc64 expects int
argument to be passed in 64bit register with bits 31..63 containing
the same value.  SYSCALL_DEFINE on ppc provides a wrapper that normalizes
the value passed from userland; so does COMPAT_SYSCALL_DEFINE.  Plain
declaration of compat_sys_something() with an int argument obviously
doesn't.  Again, for wait4 and waitid I would be extremely surprised
if gcc started to produce code depending on that value having been
properly sign-extended - the argument(s) in question end up passed
blindly to sys_wait4 and sys_waitid resp. and normalization for native
syscalls takes care of their use there.  Still, better to use
COMPAT_SYSCALL_DEFINE here than worry about nasal daemons...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-26 01:15:02 -05:00
Al Viro
90228fc110 switch compat_sys_sigaltstack() to COMPAT_SYSCALL_DEFINE
Makes sigaltstack conversion easier to split into per-architecture
parts.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-26 01:15:02 -05:00
Eric W. Biederman
c876ad7682 pidns: Stop pid allocation when init dies
Oleg pointed out that in a pid namespace the sequence.
- pid 1 becomes a zombie
- setns(thepidns), fork,...
- reaping pid 1.
- The injected processes exiting.

Can lead to processes attempting access their child reaper and
instead following a stale pointer.

That waitpid for init can return before all of the processes in
the pid namespace have exited is also unfortunate.

Avoid these problems by disabling the allocation of new pids in a pid
namespace when init dies, instead of when the last process in a pid
namespace is reaped.

Pointed-out-by:  Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-12-25 16:10:05 -08:00
Eric W. Biederman
8382fcac1b pidns: Outlaw thread creation after unshare(CLONE_NEWPID)
The sequence:
unshare(CLONE_NEWPID)
clone(CLONE_THREAD|CLONE_SIGHAND|CLONE_VM)

Creates a new process in the new pid namespace without setting
pid_ns->child_reaper.  After forking this results in a NULL
pointer dereference.

Avoid this and other nonsense scenarios that can show up after
creating a new pid namespace with unshare by adding a new
check in copy_prodcess.

Pointed-out-by:  Oleg Nesterov <oleg@redhat.com>
Acked-by:  Oleg Nesterov <oleg@redhat.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-12-24 22:53:14 -08:00
Linus Torvalds
96680d2b91 Merge branch 'for-next' of git://git.infradead.org/users/eparis/notify
Pull filesystem notification updates from Eric Paris:
 "This pull mostly is about locking changes in the fsnotify system.  By
  switching the group lock from a spin_lock() to a mutex() we can now
  hold the lock across things like iput().  This fixes a problem
  involving unmounting a fs and having inodes be busy, first pointed out
  by FAT, but reproducible with tmpfs.

  This also restores signal driven I/O for inotify, which has been
  broken since about 2.6.32."

Ugh.  I *hate* the timing of this.  It was rebased after the merge
window opened, and then left to sit with the pull request coming the day
before the merge window closes.  That's just crap.  But apparently the
patches themselves have been around for over a year, just gathering
dust, so now it's suddenly critical.

Fixed up semantic conflict in fs/notify/fdinfo.c as per Stephen
Rothwell's fixes from -next.

* 'for-next' of git://git.infradead.org/users/eparis/notify:
  inotify: automatically restart syscalls
  inotify: dont skip removal of watch descriptor if creation of ignored event failed
  fanotify: dont merge permission events
  fsnotify: make fasync generic for both inotify and fanotify
  fsnotify: change locking order
  fsnotify: dont put marks on temporary list when clearing marks by group
  fsnotify: introduce locked versions of fsnotify_add_mark() and fsnotify_remove_mark()
  fsnotify: pass group to fsnotify_destroy_mark()
  fsnotify: use a mutex instead of a spinlock to protect a groups mark list
  fanotify: add an extra flag to mark_remove_from_mask that indicates wheather a mark should be destroyed
  fsnotify: take groups mark_lock before mark lock
  fsnotify: use reference counting for groups
  fsnotify: introduce fsnotify_get_group()
  inotify, fanotify: replace fsnotify_put_group() with fsnotify_destroy_group()
2012-12-20 20:11:52 -08:00