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6892 commits

Author SHA1 Message Date
Yinghai Lu
eaa958402e cpumask: alloc zeroed cpumask for static cpumask_var_ts
These are defined as static cpumask_var_t so if MAXSMP is not used,
they are cleared already.  Avoid surprises when MAXSMP is enabled.

Signed-off-by: Yinghai Lu <yinghai.lu@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-09 22:30:27 +09:30
Linus Torvalds
3af968e066 async: Fix lack of boot-time console due to insufficient synchronization
Our async work synchronization was broken by "async: make sure
independent async domains can't accidentally entangle" (commit
d5a877e8dd), because it would report
the wrong lowest active async ID when there was both running and
pending async work.

This caused things like no being able to read the root filesystem,
resulting in missing console devices and inability to run 'init',
causing a boot-time panic.

This fixes it by properly returning the lowest pending async ID: if
there is any running async work, that will have a lower ID than any
pending work, and we should _not_ look at the pending work list.

There were alternative patches from Jaswinder and James, but this one
also cleans up the code by removing the pointless 'ret' variable and
the unnecesary testing for an empty list around 'for_each_entry()' (if
the list is empty, the for_each_entry() thing just won't execute).

Fixes-bug: http://bugzilla.kernel.org/show_bug.cgi?id=13474
Reported-and-tested-by: Chris Clayton <chris2553@googlemail.com>
Cc: Jaswinder Singh Rajput <jaswinder@kernel.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-08 12:31:53 -07:00
Oleg Nesterov
edaba2c533 ptrace: revert "ptrace_detach: the wrong wakeup breaks the ERESTARTxxx logic"
Commit 95a3540da9 ("ptrace_detach: the wrong
wakeup breaks the ERESTARTxxx logic") removed the "extra"
wake_up_process() from ptrace_detach(), but as Jan pointed out this breaks
the compatibility.

I believe the changelog is right and this wake_up() is wrong in many
ways, but GDB assumes that ptrace(PTRACE_DETACH, child, 0, 0) always
wakes up the tracee.

Despite the fact this breaks SIGNAL_STOP_STOPPED/group_stop_count logic,
and despite the fact this wake_up_process() can break another
assumption: PTRACE_DETACH with SIGSTOP should leave the tracee in
TASK_STOPPED case.  Because the untraced child can dequeue SIGSTOP and
call do_signal_stop() before ptrace_detach() calls wake_up_process().

Revert this change for now.  We need some fixes even if we we want to keep
the current behaviour, but these fixes are not for 2.6.30.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-04 18:07:40 -07:00
Oleg Nesterov
087eb43705 ptrace: tracehook_report_clone: fix false positives
The "trace || CLONE_PTRACE" check in tracehook_report_clone() is not right,

- If the untraced task does clone(CLONE_PTRACE) the new child is not traced,
  we must not queue SIGSTOP.

- If we forked the traced task, but the tracer exits and untraces both the
  forking task and the new child (after copy_process() drops tasklist_lock),
  we should not queue SIGSTOP too.

Change the code to check task_ptrace() != 0 instead. This is still racy, but
the race is harmless.

We can race with another tracer attaching to this child, or the tracer can
exit and detach in parallel. But giwen that we didn't do wake_up_new_task()
yet, the child must have the pending SIGSTOP anyway.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-04 18:07:40 -07:00
Tetsuo Handa
ab2b7ebaad kmod: Release sub_info on cred allocation failure.
call_usermodehelper_setup() forgot to kfree(sub_info)
when prepare_usermodehelper_creds() failed.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-26 12:11:19 -07:00
Linus Torvalds
93c3248380 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
  PM: Do not hold dpm_list_mtx while disabling/enabling nonboot CPUs
2009-05-24 19:38:25 -07:00
James Bottomley
d5a877e8dd async: make sure independent async domains can't accidentally entangle
The problem occurs when async_synchronize_full_domain() is called when
the async_pending list is not empty.  This will cause lowest_running()
to return the cookie of the first entry on the async_pending list, which
might be nothing at all to do with the domain being asked for and thus
cause the domain synchronization to wait for an unrelated domain.   This
can cause a deadlock if domain synchronization is used from one domain
to wait for another.

Fix by running over the async_pending list to see if any pending items
actually belong to our domain (and return their cookies if they do).

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-24 13:38:41 -07:00
Rafael J. Wysocki
32bdfac546 PM: Do not hold dpm_list_mtx while disabling/enabling nonboot CPUs
We shouldn't hold dpm_list_mtx while executing
[disable|enable]_nonboot_cpus(), because theoretically this may lead
to a deadlock as shown by the following example (provided by Johannes
Berg):

CPU 3       CPU 2                     CPU 1
                                      suspend/hibernate
            something:
            rtnl_lock()               device_pm_lock()
                                       -> mutex_lock(&dpm_list_mtx)

            mutex_lock(&dpm_list_mtx)

linkwatch_work
 -> rtnl_lock()
                                      disable_nonboot_cpus()
                                       -> flush CPU 3 workqueue

Fortunately, device drivers are supposed to stop any activities that
might lead to the registration of new device objects way before
disable_nonboot_cpus() is called, so it shouldn't be necessary to
hold dpm_list_mtx over the entire late part of device suspend and
early part of device resume.

Thus, during the late suspend and the early resume of devices acquire
dpm_list_mtx only when dpm_list is going to be traversed and release
it right after that.

This patch is reported to fix the regressions tracked as
http://bugzilla.kernel.org/show_bug.cgi?id=13245.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Miles Lane <miles.lane@gmail.com>
Tested-by: Ming Lei <tom.leiming@gmail.com>
2009-05-24 21:15:07 +02:00
Thomas Gleixner
64d1304a64 futex: setup writeable mapping for futex ops which modify user space data
The futex code installs a read only mapping via get_user_pages_fast()
even if the futex op function has to modify user space data. The
eventual fault was fixed up by futex_handle_fault() which walked the
VMA with mmap_sem held.

After the cleanup patches which removed the mmap_sem dependency of the
futex code commit 4dc5b7a36a49eff97050894cf1b3a9a02523717 (futex:
clean up fault logic) removed the private VMA walk logic from the
futex code. This change results in a stale RO mapping which is not
fixed up.

Instead of reintroducing the previous fault logic we set up the
mapping in get_user_pages_fast() read/write for all operations which
modify user space data. Also handle private futexes in the same way
and make the current unconditional access_ok(VERIFY_WRITE) depend on
the futex op.

Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
CC: stable@kernel.org
2009-05-19 23:36:52 +02:00
Linus Torvalds
ee3af6ee77 Merge branches 'sched-fixes-for-linus-2' and 'core-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Fix fallback sched_clock()'s offset when using jiffies

* 'core-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  lockdep: increase MAX_LOCKDEP_ENTRIES and MAX_LOCKDEP_CHAINS
2009-05-18 10:11:06 -07:00
Linus Torvalds
0130b2d701 Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: Append prompt in /debug/tracing/README file
  x86/function-graph: fix constraint for recording old return value
2009-05-18 09:15:41 -07:00
Linus Torvalds
86460103c4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
  PM: check sysdev_suspend(PMSG_FREEZE) return value
2009-05-17 11:46:22 -07:00
Linus Torvalds
0f6f49a8cd Fix caller information for warn_slowpath_null
Ian Campbell noticed that since "Eliminate thousands of warnings with
gcc 3.2 build" (commit 57adc4d2db) all
WARN_ON()'s currently appear to come from warn_slowpath_null(), eg:

  WARNING: at kernel/softirq.c:143 warn_slowpath_null+0x1c/0x20()

because now that warn_slowpath_null() is in the call path, the
__builtin_return_address(0) returns that, rather than the place that
caused the warning.

Fix this by splitting up the warn_slowpath_null/fmt cases differently,
using a common helper function, and getting the return address in the
right place.  This also happens to avoid the unnecessary stack usage for
the non-stdargs case, and just generally cleans things up.

Make the function name printout use %pS while at it.

Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-16 13:41:28 -07:00
Bjorn Helgaas
4484079d51 PM: check sysdev_suspend(PMSG_FREEZE) return value
Check the return value of sysdev_suspend().  I think this was a typo.
Without this change, the following "if" check is always false.
I also changed the error message so it's distinguishable from the
similar message a few lines above.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-05-15 23:30:50 +02:00
GeunSik Lim
88fc86c283 tracing: Append prompt in /debug/tracing/README file
append prompt in /debug/tracing/README file.

This is trivial issue. Fix typo Mini Howto file(README) for ftrace.

[ Impact: cleanup ]

Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: williams <williams@redhat.com>
LKML-Reference: <1242289418.31161.45.camel@centos51>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-15 19:43:22 +02:00
Linus Torvalds
ade385e4d1 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
  kgdb: gdb documentation fix
  kgdb,i386: use address that SP register points to in the exception frame
  sysrq, intel_fb: fix sysrq g collision
2009-05-15 08:06:45 -07:00
Jason Wessel
364b5b7b1d sysrq, intel_fb: fix sysrq g collision
Commit 79e539453b introduced a
regression where you cannot use sysrq 'g' to enter kgdb.  The solution
is to move the intel fb sysrq over to V for video instead of G for
graphics.  The SMP VOYAGER code to register for the sysrq-v is not
anywhere to be found in the mainline kernel, so the comments in the
code were cleaned up as well.

This patch also cleans up the sysrq definitions for kgdb to make it
generic for the kernel debugger, such that the sysrq 'g' can be used
in the future to enter a gdbstub or another kernel debugger.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2009-05-15 07:56:24 -05:00
Jens Axboe
cd17cbfda0 Revert "mm: add /proc controls for pdflush threads"
This reverts commit fafd688e4c.

Work is progressing to switch away from pdflush as the process backing
for flushing out dirty data. So it seems pointless to add more knobs
to control pdflush threads. The original author of the patch did not
have any specific use cases for adding the knobs, so we can easily
revert this before 2.6.30 to avoid having to maintain this API
forever.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-15 11:32:24 +02:00
Ingo Molnar
d80c19df5f lockdep: increase MAX_LOCKDEP_ENTRIES and MAX_LOCKDEP_CHAINS
Now that lockdep coverage has increased it has become easier to
run out of entries:

[   21.401387] BUG: MAX_LOCKDEP_ENTRIES too low!
[   21.402007] turning off the locking correctness validator.
[   21.402007] Pid: 1555, comm: S99local Not tainted 2.6.30-rc5-tip #2
[   21.402007] Call Trace:
[   21.402007]  [<ffffffff81069789>] add_lock_to_list+0x53/0xba
[   21.402007]  [<ffffffff810eb615>] ? lookup_mnt+0x19/0x53
[   21.402007]  [<ffffffff8106be14>] check_prev_add+0x14b/0x1c7
[   21.402007]  [<ffffffff8106c304>] validate_chain+0x474/0x52a
[   21.402007]  [<ffffffff8106c6fc>] __lock_acquire+0x342/0x3c7
[   21.402007]  [<ffffffff8106c842>] lock_acquire+0xc1/0xe5
[   21.402007]  [<ffffffff810eb615>] ? lookup_mnt+0x19/0x53
[   21.402007]  [<ffffffff8153aedc>] _spin_lock+0x31/0x66

Double the size - as we've done in the past.

[ Impact: allow lockdep to cover more locks ]

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-12 19:59:52 +02:00
Al Viro
6f5bbff9a1 Convert obvious places to deactivate_locked_super()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-09 10:49:40 -04:00
Ron
92d23f703c sched: Fix fallback sched_clock()'s offset when using jiffies
Account for the initial offset to the jiffy count.

[ Impact: fix printk timestamps on architectures using fallback sched_clock() ]

Signed-off-by: Ron Lee <ron@debian.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-09 10:08:19 +02:00
Masami Hiramatsu
201517a7f3 kprobes: fix to use text_mutex around arm/disarm kprobe
Fix kprobes to lock text_mutex around some arch_arm/disarm_kprobe() which
are newly added by commit de5bd88d5a.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-08 16:23:48 -07:00
Andi Kleen
57adc4d2db Eliminate thousands of warnings with gcc 3.2 build
When building with gcc 3.2 I get thousands of warnings such as

include/linux/gfp.h: In function `allocflags_to_migratetype':
include/linux/gfp.h:105: warning: null format string

due to passing a NULL format string to warn_slowpath() in

#define __WARN()		warn_slowpath(__FILE__, __LINE__, NULL)

Split this case out into a separate call.  This also shrinks the kernel
slightly:

          text    data     bss     dec     hex filename
       4802274  707668  712704 6222646  5ef336 vmlinux
          text    data     bss     dec     hex filename
       4799027  703572  712704 6215303  5ed687 vmlinux

due to removeing one argument from the commonly-called __WARN().

[akpm@linux-foundation.org: reduce scope of `empty']
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-06 16:36:09 -07:00
Wu Fengguang
381a80e6df inotify: use GFP_NOFS in kernel_event() to work around a lockdep false-positive
There is what we believe to be a false positive reported by lockdep.

inotify_inode_queue_event() => take inotify_mutex => kernel_event() =>
kmalloc() => SLOB => alloc_pages_node() => page reclaim => slab reclaim =>
dcache reclaim => inotify_inode_is_dead => take inotify_mutex => deadlock

The plan is to fix this via lockdep annotation, but that is proving to be
quite involved.

The patch flips the allocation over to GFP_NFS to shut the warning up, for
the 2.6.30 release.

Hopefully we will fix this for real in 2.6.31.  I'll queue a patch in -mm
to switch it back to GFP_KERNEL so we don't forget.

  =================================
  [ INFO: inconsistent lock state ]
  2.6.30-rc2-next-20090417 #203
  ---------------------------------
  inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage.
  kswapd0/380 [HC0[0]:SC0[0]:HE1:SE1] takes:
   (&inode->inotify_mutex){+.+.?.}, at: [<ffffffff8112f1b5>] inotify_inode_is_dead+0x35/0xb0
  {RECLAIM_FS-ON-W} state was registered at:
    [<ffffffff81079188>] mark_held_locks+0x68/0x90
    [<ffffffff810792a5>] lockdep_trace_alloc+0xf5/0x100
    [<ffffffff810f5261>] __kmalloc_node+0x31/0x1e0
    [<ffffffff81130652>] kernel_event+0xe2/0x190
    [<ffffffff81130826>] inotify_dev_queue_event+0x126/0x230
    [<ffffffff8112f096>] inotify_inode_queue_event+0xc6/0x110
    [<ffffffff8110444d>] vfs_create+0xcd/0x140
    [<ffffffff8110825d>] do_filp_open+0x88d/0xa20
    [<ffffffff810f6b68>] do_sys_open+0x98/0x140
    [<ffffffff810f6c50>] sys_open+0x20/0x30
    [<ffffffff8100c272>] system_call_fastpath+0x16/0x1b
    [<ffffffffffffffff>] 0xffffffffffffffff
  irq event stamp: 690455
  hardirqs last  enabled at (690455): [<ffffffff81564fe4>] _spin_unlock_irqrestore+0x44/0x80
  hardirqs last disabled at (690454): [<ffffffff81565372>] _spin_lock_irqsave+0x32/0xa0
  softirqs last  enabled at (690178): [<ffffffff81052282>] __do_softirq+0x202/0x220
  softirqs last disabled at (690157): [<ffffffff8100d50c>] call_softirq+0x1c/0x50

  other info that might help us debug this:
  2 locks held by kswapd0/380:
   #0:  (shrinker_rwsem){++++..}, at: [<ffffffff810d0bd7>] shrink_slab+0x37/0x180
   #1:  (&type->s_umount_key#17){++++..}, at: [<ffffffff8110cfbf>] shrink_dcache_memory+0x11f/0x1e0

  stack backtrace:
  Pid: 380, comm: kswapd0 Not tainted 2.6.30-rc2-next-20090417 #203
  Call Trace:
   [<ffffffff810789ef>] print_usage_bug+0x19f/0x200
   [<ffffffff81018bff>] ? save_stack_trace+0x2f/0x50
   [<ffffffff81078f0b>] mark_lock+0x4bb/0x6d0
   [<ffffffff810799e0>] ? check_usage_forwards+0x0/0xc0
   [<ffffffff8107b142>] __lock_acquire+0xc62/0x1ae0
   [<ffffffff810f478c>] ? slob_free+0x10c/0x370
   [<ffffffff8107c0a1>] lock_acquire+0xe1/0x120
   [<ffffffff8112f1b5>] ? inotify_inode_is_dead+0x35/0xb0
   [<ffffffff81562d43>] mutex_lock_nested+0x63/0x420
   [<ffffffff8112f1b5>] ? inotify_inode_is_dead+0x35/0xb0
   [<ffffffff8112f1b5>] ? inotify_inode_is_dead+0x35/0xb0
   [<ffffffff81012fe9>] ? sched_clock+0x9/0x10
   [<ffffffff81077165>] ? lock_release_holdtime+0x35/0x1c0
   [<ffffffff8112f1b5>] inotify_inode_is_dead+0x35/0xb0
   [<ffffffff8110c9dc>] dentry_iput+0xbc/0xe0
   [<ffffffff8110cb23>] d_kill+0x33/0x60
   [<ffffffff8110ce23>] __shrink_dcache_sb+0x2d3/0x350
   [<ffffffff8110cffa>] shrink_dcache_memory+0x15a/0x1e0
   [<ffffffff810d0cc5>] shrink_slab+0x125/0x180
   [<ffffffff810d1540>] kswapd+0x560/0x7a0
   [<ffffffff810ce160>] ? isolate_pages_global+0x0/0x2c0
   [<ffffffff81065a30>] ? autoremove_wake_function+0x0/0x40
   [<ffffffff8107953d>] ? trace_hardirqs_on+0xd/0x10
   [<ffffffff810d0fe0>] ? kswapd+0x0/0x7a0
   [<ffffffff8106555b>] kthread+0x5b/0xa0
   [<ffffffff8100d40a>] child_rip+0xa/0x20
   [<ffffffff8100cdd0>] ? restore_args+0x0/0x30
   [<ffffffff81065500>] ? kthread+0x0/0xa0
   [<ffffffff8100d400>] ? child_rip+0x0/0x20

[eparis@redhat.com: fix audit too]
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-06 16:36:09 -07:00
Linus Torvalds
99ee12973e Merge branch 'timers/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  clockevents: prevent endless loop in tick_handle_periodic()
2009-05-05 12:09:38 -07:00
Linus Torvalds
bcb1656827 Merge branch 'irq/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  Revert "genirq: assert that irq handlers are indeed running in hardirq context"
2009-05-05 12:09:27 -07:00
Linus Torvalds
e858e8b076 Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: account system time properly
2009-05-05 12:08:40 -07:00
Linus Torvalds
da87bbd142 Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  kernel/posix-cpu-timers.c: fix sparse warning
  dma-debug: remove broken dma memory leak detection for 2.6.30
  locking: Documentation: lockdep-design.txt, fix note of state bits
2009-05-05 12:08:20 -07:00
Linus Torvalds
e91b3b2681 Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: x86, mmiotrace: fix range test
  tracing: fix ref count in splice pages
2009-05-05 12:08:02 -07:00
Andrea Righi
9e4a5bda89 mm: prevent divide error for small values of vm_dirty_bytes
Avoid setting less than two pages for vm_dirty_bytes: this is necessary to
avoid potential division by 0 (like the following) in get_dirty_limits().

[   49.951610] divide error: 0000 [#1] PREEMPT SMP
[   49.952195] last sysfs file: /sys/devices/pci0000:00/0000:00:01.1/host0/target0:0:0/0:0:0:0/block/sda/uevent
[   49.952195] CPU 1
[   49.952195] Modules linked in: pcspkr
[   49.952195] Pid: 3064, comm: dd Not tainted 2.6.30-rc3 #1
[   49.952195] RIP: 0010:[<ffffffff802d39a9>]  [<ffffffff802d39a9>] get_dirty_limits+0xe9/0x2c0
[   49.952195] RSP: 0018:ffff88001de03a98  EFLAGS: 00010202
[   49.952195] RAX: 00000000000000c0 RBX: ffff88001de03b80 RCX: 28f5c28f5c28f5c3
[   49.952195] RDX: 0000000000000000 RSI: 00000000000000c0 RDI: 0000000000000000
[   49.952195] RBP: ffff88001de03ae8 R08: 0000000000000000 R09: 0000000000000000
[   49.952195] R10: ffff88001ddda9a0 R11: 0000000000000001 R12: 0000000000000001
[   49.952195] R13: ffff88001fbc8218 R14: ffff88001de03b70 R15: ffff88001de03b78
[   49.952195] FS:  00007fe9a435b6f0(0000) GS:ffff8800025d9000(0000) knlGS:0000000000000000
[   49.952195] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   49.952195] CR2: 00007fe9a39ab000 CR3: 000000001de38000 CR4: 00000000000006e0
[   49.952195] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   49.952195] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[   49.952195] Process dd (pid: 3064, threadinfo ffff88001de02000, task ffff88001ddda250)
[   49.952195] Stack:
[   49.952195]  ffff88001fa0de00 ffff88001f2dbd70 ffff88001f9fe800 000080b900000000
[   49.952195]  00000000000000c0 ffff8800027a6100 0000000000000400 ffff88001fbc8218
[   49.952195]  0000000000000000 0000000000000600 ffff88001de03bb8 ffffffff802d3ed7
[   49.952195] Call Trace:
[   49.952195]  [<ffffffff802d3ed7>] balance_dirty_pages_ratelimited_nr+0x1d7/0x3f0
[   49.952195]  [<ffffffff80368f8e>] ? ext3_writeback_write_end+0x9e/0x120
[   49.952195]  [<ffffffff802cc7df>] generic_file_buffered_write+0x12f/0x330
[   49.952195]  [<ffffffff802cce8d>] __generic_file_aio_write_nolock+0x26d/0x460
[   49.952195]  [<ffffffff802cda32>] ? generic_file_aio_write+0x52/0xd0
[   49.952195]  [<ffffffff802cda49>] generic_file_aio_write+0x69/0xd0
[   49.952195]  [<ffffffff80365fa6>] ext3_file_write+0x26/0xc0
[   49.952195]  [<ffffffff803034d1>] do_sync_write+0xf1/0x140
[   49.952195]  [<ffffffff80290d1a>] ? get_lock_stats+0x2a/0x60
[   49.952195]  [<ffffffff80280730>] ? autoremove_wake_function+0x0/0x40
[   49.952195]  [<ffffffff8030411b>] vfs_write+0xcb/0x190
[   49.952195]  [<ffffffff803042d0>] sys_write+0x50/0x90
[   49.952195]  [<ffffffff8022ff6b>] system_call_fastpath+0x16/0x1b
[   49.952195] Code: 00 00 00 2b 05 09 1c 17 01 48 89 c6 49 0f af f4 48 c1 ee 02 48 89 f0 48 f7 e1 48 89 d6 31 d2 48 c1 ee 02 48 0f af 75 d0 48 89 f0 <48> f7 f7 41 8b 95 ac 01 00 00 48 89 c7 49 0f af d4 48 c1 ea 02
[   49.952195] RIP  [<ffffffff802d39a9>] get_dirty_limits+0xe9/0x2c0
[   49.952195]  RSP <ffff88001de03a98>
[   50.096523] ---[ end trace 008d7aa02f244d7b ]---

Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-02 15:36:10 -07:00
john stultz
74a03b69d1 clockevents: prevent endless loop in tick_handle_periodic()
tick_handle_periodic() can lock up hard when a one shot clock event
device is used in combination with jiffies clocksource.

Avoid an endless loop issue by requiring that a highres valid
clocksource be installed before we call tick_periodic() in a loop when
using ONESHOT mode. The result is we will only increment jiffies once
per interrupt until a continuous hardware clocksource is available.

Without this, we can run into a endless loop, where each cycle through
the loop, jiffies is updated which increments time by tick_period or
more (due to clock steering), which can cause the event programming to
think the next event was before the newly incremented time and fail
causing tick_periodic() to be called again and the whole process loops
forever.

[ Impact: prevent hard lock up ]

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
2009-05-02 10:22:27 +02:00
Thomas Gleixner
d7226fb6ec Revert "genirq: assert that irq handlers are indeed running in hardirq context"
This reverts commit 044d408409.

The commit added a warning when handle_IRQ_event() is called outside
of hard interrupt context. This breaks the generic tasklet based
interrupt resend mechanism which is used when the hardware has no way
to retrigger the interrupt. So we get a warning for a use case which
is correct and worked for years. Remove it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-05-01 15:16:04 +02:00
H Hartley Sweeten
6e85c5ba73 kernel/posix-cpu-timers.c: fix sparse warning
Sparse reports the following in kernel/posix-cpu-timers.c:

  warning: symbol 'firing' shadows an earlier one

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Subrata Modak <subrata@linux.vnet.ibm.com>
LKML-Reference: <BD79186B4FD85F4B8E60E381CAEE1909016C1AFE@mi8nycmail19.Mi8.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-30 08:08:31 +02:00
Eric Dumazet
f5f293a4e3 sched: account system time properly
Andrew Gallatin reported that IRQ and SOFTIRQ times were
sometime not reported correctly on recent kernels, and even
bisected to commit 457533a7d3
([PATCH] fix scaled & unscaled cputime accounting) as the first
bad commit.

Further analysis pointed that commit
79741dd357 ([PATCH] idle cputime
accounting) was the real cause of the problem.

account_process_tick() was not taking into account timer IRQ
interrupting the idle task servicing a hard or soft irq.

On mostly idle cpu, irqs were thus not accounted and top or
mpstat could tell user/admin that cpu was 100 % idle, 0.00 %
irq, 0.00 % softirq, while it was not.

[ Impact: fix occasionally incorrect CPU statistics in top/mpstat ]

Reported-by: Andrew Gallatin <gallatin@myri.com>
Re-reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: rick.jones2@hp.com
Cc: brice@myri.com
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
LKML-Reference: <49F84BC1.7080602@cosmosbay.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-29 15:02:28 +02:00
Steven Rostedt
7267fa6819 tracing: fix ref count in splice pages
The pages allocated for the splice binary buffer did not initialize
the ref count correctly. This caused pages not to be freed and causes
a drastic memory leak.

Thanks to logdev I was able to trace the tracer to find where the leak
was.

[ Impact: stop memory leak when using splice ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-29 08:02:44 +02:00
Linus Torvalds
51b3960e78 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  ptrace: ptrace_attach: fix the usage of ->cred_exec_mutex
2009-04-27 08:38:51 -07:00
Oleg Nesterov
cad81bc252 ptrace: ptrace_attach: fix the usage of ->cred_exec_mutex
ptrace_attach() needs task->cred_exec_mutex, not current->cred_exec_mutex.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-04-27 20:30:51 +10:00
Linus Torvalds
fc2e3180a7 Merge branch 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86/irq: mark NUMA_MIGRATE_IRQ_DESC broken
  x86, irq: Remove IRQ_DISABLED check in process context IRQ move
2009-04-26 10:29:18 -07:00
Linus Torvalds
1e4b978154 Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  locking: clarify kernel-taint warning message
  lockdep, x86: account for irqs enabled in paranoid_exit
  lockdep: more robust lockdep_map init sequence
2009-04-26 10:29:01 -07:00
Rafael J. Wysocki
0c8454f566 PM/Hibernate: Fix waiting for image device to appear on resume
Commit c751085943 ("PM/Hibernate: Wait for
SCSI devices scan to complete during resume") added a call to
scsi_complete_async_scans() to software_resume(), so that it waited for
the SCSI scanning to complete, but the call was added at a wrong place.

Namely, it should have been added after wait_for_device_probe(), which
is called only if the image partition hasn't been specified yet.  Also,
it's reasonable to check if the image partition is present and only wait
for the device probing and SCSI scanning to complete if it is not the
case.

Additionally, since noresume is checked right at the beginning of
software_resume() and the function returns immediately if it's set, it
doesn't make sense to check it once again later.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-24 15:31:30 -07:00
Jonathan Corbet
418df63c2d Delete slow-work timers properly
Slow-work appears to delete its timer as soon as the first user
unregisters, even though other users could be active.  At the same time, it
never seems to delete slow_work_oom_timer.  Arrange for both to happen in
the shutdown path.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-24 07:47:59 -07:00
Ingo Molnar
b48ccb095a locking: clarify kernel-taint warning message
Andi Kleen reported this message triggering on non-lockdep kernels:

   Disabling lockdep due to kernel taint

Clarify the message to say 'lock debugging' - debug_locks_off()
turns off all things lock debugging, not just lockdep.

[ Impact: change kernel warning message text ]

Reported-by: Andi Kleen <andi@firstfloor.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-23 09:36:52 +02:00
Magnus Damm
4614e6adaf clocksource: add enable() and disable() callbacks
Add enable() and disable() callbacks for clocksources.

This allows us to put unused clocksources in power save mode.  The
functions clocksource_enable() and clocksource_disable() wrap the
callbacks and are inserted in the timekeeping code to enable before use
and disable after switching to a new clocksource.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 13:41:47 -07:00
Magnus Damm
8e19608e8b clocksource: pass clocksource to read() callback
Pass clocksource pointer to the read() callback for clocksources.  This
allows us to share the callback between multiple instances.

[hugh@veritas.com: fix powerpc build of clocksource pass clocksource mods]
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 13:41:47 -07:00
Al Viro
24b6f16ecf No need for crossing to mountpoint in audit_tag_tree()
is_under() will DTRT anyway.  And yes, is_subdir() behaviour
is intentional.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-20 23:01:15 -04:00
Rafael J. Wysocki
6a7c7eaf71 PM/Suspend: Introduce two new platform callbacks to avoid breakage
Commit 900af0d973 (PM: Change suspend
code ordering) changed the ordering of suspend code in such a way
that the platform .prepare() callback is now executed after the
device drivers' late suspend callbacks have run.  Unfortunately, this
turns out to break ARM platforms that need to talk via I2C to power
control devices during the .prepare() callback.

For this reason introduce two new platform suspend callbacks,
.prepare_late() and .wake(), that will be called just prior to
disabling non-boot CPUs and right after bringing them back on line,
respectively, and use them instead of .prepare() and .finish() for
ACPI suspend.  Make the PM core execute the .prepare() and .finish()
platform suspend callbacks where they were executed previously (that
is, right after calling the regular suspend methods provided by
device drivers and right before executing their regular resume
methods, respectively).

It is not necessary to make analogous changes to the hibernation
code and data structures at the moment, because they are only used
by ACPI platforms.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Len Brown <len.brown@intel.com>
2009-04-19 20:08:42 +02:00
Linus Torvalds
ff54250a0e Remove 'recurse into child resources' logic from 'reserve_region_with_split()'
This function is not actually used right now, since the original use
case for it was done with insert_resource_expand_to_fit() instead.

However, we now have another usage case that wants to basically do a
"reserve IO resource, splitting around existing resources", however that
one doesn't actually want the "recurse into the conflicting resource"
logic at all.

And since recursing into the conflicting resource was the most complex
part, and isn't wanted, just remove it.  Maybe we'll some day want both
versions, but we can just resurrect the logic then.

Tested-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-18 21:44:24 -07:00
Peter Zijlstra
c8a2500586 lockdep: more robust lockdep_map init sequence
Steven Rostedt reported:

> OK, I think I figured this bug out. This is a lockdep issue with respect
> to tracepoints.
>
> The trace points in lockdep are called all the time. Outside the lockdep
> logic. But if lockdep were to trigger an error / warning (which this run
> did) we might be in trouble. For new locks, like the dentry->d_lock, that
> are created, they will not get a name:
>
> void lockdep_init_map(struct lockdep_map *lock, const char *name,
>                       struct lock_class_key *key, int subclass)
> {
>         if (unlikely(!debug_locks))
>                 return;
>
> When a problem is found by lockdep, debug_locks becomes false. Thus we
> stop allocating names for locks. This dentry->d_lock I had, now has no
> name. Worse yet, I have CONFIG_DEBUG_VM set, that scrambles non
> initialized memory. Thus, when the trace point was hit, it had junk for
> the lock->name, and the machine crashed.

Ah, nice catch. I think we should put at least the name in regardless.

Ensure we at least initialize the trivial entries of the depmap so that
they can be relied upon, even when lockdep itself decided to pack up and
go home.

[ Impact: fix lock tracing after lockdep warnings. ]

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1239954049.23397.4156.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-17 18:00:00 +02:00
Linus Torvalds
9f76208c33 Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: Fix branch tracer header
  tracing: Fix power tracer header
2009-04-16 18:17:22 -07:00
Linus Torvalds
d06be22150 Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Avoid printing sched_group::__cpu_power for default case
  tracing, sched: mark get_parent_ip() notrace
2009-04-16 18:16:29 -07:00