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Commit Graph

233236 Commits

Author SHA1 Message Date
Linus Torvalds
007a14af26 Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: check return value of alloc_extent_map()
  Btrfs - Fix memory leak in btrfs_init_new_device()
  btrfs: prevent heap corruption in btrfs_ioctl_space_info()
  Btrfs: Fix balance panic
  Btrfs: don't release pages when we can't clear the uptodate bits
  Btrfs: fix page->private races
2011-02-15 08:00:35 -08:00
Martin Schwidefsky
261cd298a8 s390: remove task_show_regs
task_show_regs used to be a debugging aid in the early bringup days
of Linux on s390. /proc/<pid>/status is a world readable file, it
is not a good idea to show the registers of a process. The only
correct fix is to remove task_show_regs.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-15 07:34:16 -08:00
Linus Torvalds
1abe3af271 Merge branch 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm:
  ARM: 6657/1: hw_breakpoint: fix ptrace breakpoint advertising on unsupported arch
  ARM: 6656/1: hw_breakpoint: avoid UNPREDICTABLE behaviour when reading DBGDSCR
  ARM: 6658/1: collie: do actually pass locomo_info to locomo driver
  ARM: 6659/1: Thumb-2: Make CONFIG_OABI_COMPAT depend on !CONFIG_THUMB2_KERNEL
  ARM: 6654/1: perf/oprofile: fix off-by-one in stack check
  ARM: fixup SMP alternatives in modules
  ARM: make SWP emulation explicit on !CPU_USE_DOMAINS
  ARM: Avoid building unsafe kernels on OMAP2 and MX3
  ARM: pxa: Properly configure PWM period for palm27x
  ARM: pxa: only save/restore registers when pm functions are defined
  ARM: pxa/colibri: use correct SD detect pin
  ARM: pxa: fix mfpr_sync to read from valid offset
2011-02-14 14:49:29 -08:00
Tsutomu Itoh
c26a920373 Btrfs: check return value of alloc_extent_map()
I add the check on the return value of alloc_extent_map() to several places.
In addition, alloc_extent_map() returns only the address or NULL.
Therefore, check by IS_ERR() is unnecessary. So, I remove IS_ERR() checking.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-02-14 16:21:37 -05:00
Ilya Dryomov
67100f255d Btrfs - Fix memory leak in btrfs_init_new_device()
Memory allocated by calling kstrdup() should be freed.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-02-14 16:21:31 -05:00
Dan Rosenberg
51788b1bdd btrfs: prevent heap corruption in btrfs_ioctl_space_info()
Commit bf5fc093c5 refactored
btrfs_ioctl_space_info() and introduced several security issues.

space_args.space_slots is an unsigned 64-bit type controlled by a
possibly unprivileged caller.  The comparison as a signed int type
allows providing values that are treated as negative and cause the
subsequent allocation size calculation to wrap, or be truncated to 0.
By providing a size that's truncated to 0, kmalloc() will return
ZERO_SIZE_PTR.  It's also possible to provide a value smaller than the
slot count.  The subsequent loop ignores the allocation size when
copying data in, resulting in a heap overflow or write to ZERO_SIZE_PTR.

The fix changes the slot count type and comparison typecast to u64,
which prevents truncation or signedness errors, and also ensures that we
don't copy more data than we've allocated in the subsequent loop.  Note
that zero-size allocations are no longer possible since there is already
an explicit check for space_args.space_slots being 0 and truncation of
this value is no longer an issue.

Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: Josef Bacik <josef@redhat.com>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-02-14 16:04:23 -05:00
Yan, Zheng
6848ad6461 Btrfs: Fix balance panic
Mark the cloned backref_node as checked in clone_backref_node()

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-02-14 16:00:03 -05:00
Linus Torvalds
15a831f253 Merge branch 'devicetree/merge' of git://git.secretlab.ca/git/linux-2.6
* 'devicetree/merge' of git://git.secretlab.ca/git/linux-2.6:
  Revert "dt: add documentation of ARM dt boot interface"
2011-02-14 10:10:37 -08:00
Linus Torvalds
f1b6a4ec27 Merge branch 'rtc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'rtc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  RTC: Fix minor compile warning
  RTC: Convert rtc drivers to use the alarm_irq_enable method
  RTC: Fix rtc driver ioctl specific shortcutting
2011-02-14 10:10:07 -08:00
Chris Mason
e3f24cc521 Btrfs: don't release pages when we can't clear the uptodate bits
Btrfs tracks uptodate state in an rbtree as well as in the
page bits.  This is supposed to enable us to use block sizes other than
the page size, but there are a few parts still missing before that
completely works.

But, our readpage routine trusts this additional range based tracking
of uptodateness, much in the same way the buffer head up to date bits
are trusted for the other filesystems.

The problem is that sometimes we need to allocate memory in order to
split records in the rbtree, even when we are just clearing bits.  This
can be difficult when our clearing function is called GFP_ATOMIC, which
can happen in the releasepage path.

So, what happens today looks like this:

releasepage called with GFP_ATOMIC
btrfs_releasepage calls clear_extent_bit
clear_extent_bit fails to allocate ram, leaving the up to date bit set
btrfs_releasepage returns success

The end result is the page being gone, but btrfs thinking the range is
up to date.   Later on if someone tries to read that same page, the
btrfs readpage code will return immediately thinking the page is already
up to date.

This commit fixes things to fail the releasepage when we can't clear the
extent state bits.  It covers both data pages and metadata tree blocks.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-02-14 13:04:01 -05:00
Chris Mason
eb14ab8ed2 Btrfs: fix page->private races
There is a race where btrfs_releasepage can drop the
page->private contents just as alloc_extent_buffer is setting
up pages for metadata.  Because of how the Btrfs page flags work,
this results in us skipping the crc on the page during IO.

This patch sovles the race by waiting until after the extent buffer
is inserted into the radix tree before it sets page private.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-02-14 13:03:52 -05:00
Grant Likely
7211da1778 Revert "dt: add documentation of ARM dt boot interface"
This reverts commit 9830fcd6f6.

The ARM dt support has not been merged yet; this documentation update
was premature.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-02-14 08:13:20 -07:00
Thomas Gleixner
6ee5859df5 Merge branch 'fortglx/2.6.38/tip/timers/rtc' of git://git.linaro.org/people/jstultz/linux into timers/urgent 2011-02-14 09:00:30 +01:00
David Miller
795abaf1e4 klist: Fix object alignment on 64-bit.
Commit c0e69a5bbc ("klist.c: bit 0 in pointer can't be used as flag")
intended to make sure that all klist objects were at least pointer size
aligned, but used the constant "4" which only works on 32-bit.

Use "sizeof(void *)" which is correct in all cases.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: stable <stable@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-13 16:54:24 -08:00
Linus Torvalds
091994cfb8 Merge branch 'spi/merge' of git://git.secretlab.ca/git/linux-2.6
* 'spi/merge' of git://git.secretlab.ca/git/linux-2.6:
  devicetree-discuss is moderated for non-subscribers
  MAINTAINERS: Add entry for GPIO subsystem
  dt: add documentation of ARM dt boot interface
  dt: Remove obsolete description of powerpc boot interface
  dt: Move device tree documentation out of powerpc directory
  spi/spi_sh_msiof: fix wrong address calculation, which leads to an Oops
2011-02-13 07:59:48 -08:00
Linus Torvalds
d8ed516f82 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
  ALSA: hda - add quirk for Ordissimo EVE using a realtek ALC662
  ALSA: hrtimer: remove superfluous tasklet invocation
  ALSA: hrtimer: handle delayed timer interrupts
  ALSA: HDA: Add subwoofer quirk for Acer Aspire 8942G
  ALSA: hda - Don't handle empty patch files
  ALSA: hda - Fix missing CA initialization for HDMI/DP
  ALSA: usbaudio - Enable the E-MU 0204 USB
  ALSA: hda - switch lfe with side in mixer for 4930g
  ASoC: Improve WM8994 digital power sequencing
  ASoC: Create an AIF1ADCDAT signal widget to match AIF2
  asoc: davinci: da830/omap-l137: correct cpu_dai_name
  ASoC: fill in snd_soc_pcm_runtime.card before calling snd_soc_dai_link.init()
2011-02-13 07:58:50 -08:00
Linus Torvalds
f00eaeea7a Revert "pci: use security_capable() when checking capablities during config space read"
This reverts commit 47970b1b2a.

It turns out it breaks several distributions.  Looks like the stricter
selinux checks fail due to selinux policies not being set to allow the
access - breaking X, but also lspci.

So while the change was clearly the RightThing(tm) to do in theory, in
practice we have backwards compatibility issues making it not work.

Reported-by: Dave Young <hidave.darkstar@gmail.com>
Acked-by: David Airlie <airlied@linux.ie>
Acked-by: Alex Riesen <raa.lkml@gmail.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-13 07:50:50 -08:00
Takashi Iwai
6146124118 Merge branch 'fix/asoc' into for-linus 2011-02-13 10:05:30 +01:00
Grant Likely
c170093d31 Merge branch 'devicetree/merge' into spi/merge 2011-02-12 23:53:34 -07:00
Paul Bolle
78bba987bc devicetree-discuss is moderated for non-subscribers
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-02-12 23:27:23 -07:00
Grant Likely
a0dc00b430 MAINTAINERS: Add entry for GPIO subsystem
I'll probably regret this....

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-12 09:46:30 -08:00
Linus Torvalds
c8e0b00ed1 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  jbd2: call __jbd2_log_start_commit with j_state_lock write locked
  ext4: serialize unaligned asynchronous DIO
  ext4: make grpinfo slab cache names static
  ext4: Fix data corruption with multi-block writepages support
  ext4: fix up ext4 error handling
  ext4: unregister features interface on module unload
  ext4: fix panic on module unload when stopping lazyinit thread
2011-02-12 09:10:24 -08:00
Theodore Ts'o
e447183180 jbd2: call __jbd2_log_start_commit with j_state_lock write locked
On an SMP ARM system running ext4, I've received a report that the
first J_ASSERT in jbd2_journal_commit_transaction has been triggering:

	J_ASSERT(journal->j_running_transaction != NULL);

While investigating possible causes for this problem, I noticed that
__jbd2_log_start_commit() is getting called with j_state_lock only
read-locked, in spite of the fact that it's possible for it might
j_commit_request.  Fix this by grabbing the necessary information so
we can test to see if we need to start a new transaction before
dropping the read lock, and then calling jbd2_log_start_commit() which
will grab the write lock.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-12 08:18:24 -05:00
Eric Sandeen
e9e3bcecf4 ext4: serialize unaligned asynchronous DIO
ext4 has a data corruption case when doing non-block-aligned
asynchronous direct IO into a sparse file, as demonstrated
by xfstest 240.

The root cause is that while ext4 preallocates space in the
hole, mappings of that space still look "new" and 
dio_zero_block() will zero out the unwritten portions.  When
more than one AIO thread is going, they both find this "new"
block and race to zero out their portion; this is uncoordinated
and causes data corruption.

Dave Chinner fixed this for xfs by simply serializing all
unaligned asynchronous direct IO.  I've done the same here.
The difference is that we only wait on conversions, not all IO.
This is a very big hammer, and I'm not very pleased with
stuffing this into ext4_file_write().  But since ext4 is
DIO_LOCKING, we need to serialize it at this high level.

I tried to move this into ext4_ext_direct_IO, but by then
we have the i_mutex already, and we will wait on the
work queue to do conversions - which must also take the
i_mutex.  So that won't work.

This was originally exposed by qemu-kvm installing to
a raw disk image with a normal sector-63 alignment.  I've
tested a backport of this patch with qemu, and it does
avoid the corruption.  It is also quite a lot slower
(14 min for package installs, vs. 8 min for well-aligned)
but I'll take slow correctness over fast corruption any day.

Mingming suggested that we can track outstanding
conversions, and wait on those so that non-sparse
files won't be affected, and I've implemented that here;
unaligned AIO to nonsparse files won't take a perf hit.

[tytso@mit.edu: Keep the mutex as a hashed array instead
 of bloating the ext4 inode]

[tytso@mit.edu: Fix up namespace issues so that global
 variables are protected with an "ext4_" prefix.]

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-12 08:17:34 -05:00
Eric Sandeen
2892c15ddd ext4: make grpinfo slab cache names static
In 2.6.37 I was running into oopses with repeated module
loads & unloads.  I tracked this down to:

fb1813f4 ext4: use dedicated slab caches for group_info structures

(this was in addition to the features advert unload problem)

The kstrdup & subsequent kfree of the cache name was causing
a double free.  In slub, at least, if I read it right it allocates
& frees the name itself, slab seems to do something different...
so in slub I think we were leaking -our- cachep->name, and double
freeing the one allocated by slub.

After getting lost in slab/slub/slob a bit, I just looked at other
sized-caches that get allocated.  jbd2, biovec, sgpool all do it
more or less the way jbd2 does.  Below patch follows the jbd2
method of dynamically allocating a cache at mount time from
a list of static names.

(This might also possibly fix a race creating the caches with
parallel mounts running).

[Folded in a fix from Dan Carpenter which fixed an off-by-one error in
the original patch]

Cc: stable@kernel.org
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-12 08:12:18 -05:00
Grant Likely
557218e2d6 MAINTAINERS: Add entry for GPIO subsystem
I'll probably regret this....

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-02-12 01:45:55 -07:00
Linus Torvalds
3c6c0d6ca3 Merge branch 'kvm-updates/2.6.38' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.38' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: SVM: Make sure KERNEL_GS_BASE is valid when loading gs_index
2011-02-11 16:30:09 -08:00
Linus Torvalds
5b49378ec1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp:
  amd64_edac: Fix DIMMs per DCTs output
2011-02-11 16:30:05 -08:00
Linus Torvalds
d40b0c3482 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm:
  dlm: use single thread workqueues
2011-02-11 16:29:57 -08:00
Linus Torvalds
3aec46c1e0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  cifs: don't always drop malformed replies on the floor (try #3)
  cifs: clean up checks in cifs_echo_request
  [CIFS] Do not send SMBEcho requests on new sockets until SMBNegotiate
2011-02-11 16:29:50 -08:00
Linus Torvalds
68c3d4b266 Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/staging
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/staging:
  hwmon: (emc1403) Fix I2C address range
  hwmon: (lm63) Consider LM64 temperature offset
2011-02-11 16:16:25 -08:00
Linus Torvalds
f7909fb835 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:
  pci: use security_capable() when checking capablities during config space read
  security: add cred argument to security_capable()
  tpm_tis: Use timeouts returned from TPM
2011-02-11 16:16:03 -08:00
Linus Torvalds
c41d40b533 Merge branch 's5p-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung
* 's5p-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
  ARM: SAMSUNG: Ensure struct sys_device is declared in plat/pm.h
  ARM: S5PV310: Cleanup System MMU
  ARM: S5PV310: Add support System MMU on SMDKV310
2011-02-11 16:15:15 -08:00
Linus Torvalds
a288465fa8 Merge branch 'next' of git://git.monstr.eu/linux-2.6-microblaze
* 'next' of git://git.monstr.eu/linux-2.6-microblaze:
  microblaze: Fix msr instruction detection
  microblaze: Fix pte_update function
  microblaze: Fix asm compilation warning
  microblaze: Fix IRQ flag handling for MSR=0
2011-02-11 16:13:53 -08:00
Julia Lawall
80d02d2736 drivers/w1/masters/omap_hdq.c: add missing clk_put
This code makes two calls to clk_get, then test both return values and
fails if either failed.

The problem is that in the first inner if, where the first call to
clk_get has failed, it don't know if the second call has failed as well.
So it don't know whether clk_get should be called on the result of the
second call.  Of course, it would be possible to test that value again.
A simpler solution is just to test the result of calling clk_get
directly after each call.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r@
position p1,p2;
expression e;
statement S;
@@

e = clk_get@p1(...)
...
if@p2 (IS_ERR(e)) S

@@
expression e;
statement S;
identifier l;
position r.p1, p2 != r.p2;
@@

*e = clk_get@p1(...)
... when != clk_put(e)
*if@p2 (...)
{
  ... when != clk_put(e)
* return ...;
}// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Amit Kucheria <amit.kucheria@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-11 16:12:20 -08:00
KAMEZAWA Hiroyuki
678ff896a3 memcg: fix leak of accounting at failure path of hugepage collapsing
mem_cgroup_uncharge_page() should be called in all failure cases after
mem_cgroup_charge_newpage() is called in huge_memory.c::collapse_huge_page()

 [ 4209.076861] BUG: Bad page state in process khugepaged  pfn:1e9800
 [ 4209.077601] page:ffffea0006b14000 count:0 mapcount:0 mapping:          (null) index:0x2800
 [ 4209.078674] page flags: 0x40000000004000(head)
 [ 4209.079294] pc:ffff880214a30000 pc->flags:2146246697418756 pc->mem_cgroup:ffffc9000177a000
 [ 4209.082177] (/A)
 [ 4209.082500] Pid: 31, comm: khugepaged Not tainted 2.6.38-rc3-mm1 #1
 [ 4209.083412] Call Trace:
 [ 4209.083678]  [<ffffffff810f4454>] ? bad_page+0xe4/0x140
 [ 4209.084240]  [<ffffffff810f53e6>] ? free_pages_prepare+0xd6/0x120
 [ 4209.084837]  [<ffffffff8155621d>] ? rwsem_down_failed_common+0xbd/0x150
 [ 4209.085509]  [<ffffffff810f5462>] ? __free_pages_ok+0x32/0xe0
 [ 4209.086110]  [<ffffffff810f552b>] ? free_compound_page+0x1b/0x20
 [ 4209.086699]  [<ffffffff810fad6c>] ? __put_compound_page+0x1c/0x30
 [ 4209.087333]  [<ffffffff810fae1d>] ? put_compound_page+0x4d/0x200
 [ 4209.087935]  [<ffffffff810fb015>] ? put_page+0x45/0x50
 [ 4209.097361]  [<ffffffff8113f779>] ? khugepaged+0x9e9/0x1430
 [ 4209.098364]  [<ffffffff8107c870>] ? autoremove_wake_function+0x0/0x40
 [ 4209.099121]  [<ffffffff8113ed90>] ? khugepaged+0x0/0x1430
 [ 4209.099780]  [<ffffffff8107c236>] ? kthread+0x96/0xa0
 [ 4209.100452]  [<ffffffff8100dda4>] ? kernel_thread_helper+0x4/0x10
 [ 4209.101214]  [<ffffffff8107c1a0>] ? kthread+0x0/0xa0
 [ 4209.101842]  [<ffffffff8100dda0>] ? kernel_thread_helper+0x0/0x10

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-11 16:12:20 -08:00
Johannes Weiner
f0fdc5e8e6 vmscan: fix zone shrinking exit when scan work is done
Commit 3e7d344970 ("mm: vmscan: reclaim order-0 and use compaction
instead of lumpy reclaim") introduced an indefinite loop in
shrink_zone().

It meant to break out of this loop when no pages had been reclaimed and
not a single page was even scanned.  The way it would detect the latter
is by taking a snapshot of sc->nr_scanned at the beginning of the
function and comparing it against the new sc->nr_scanned after the scan
loop.  But it would re-iterate without updating that snapshot, looping
forever if sc->nr_scanned changed at least once since shrink_zone() was
invoked.

This is not the sole condition that would exit that loop, but it
requires other processes to change the zone state, as the reclaimer that
is stuck obviously can not anymore.

This is only happening for higher-order allocations, where reclaim is
run back to back with compaction.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Michal Hocko <mhocko@suse.cz>
Tested-by: Kent Overstreet<kent.overstreet@gmail.com>
Reported-by: Kent Overstreet <kent.overstreet@gmail.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-11 16:12:20 -08:00
Michel Lespinasse
419d8c96db mlock: do not munlock pages in __do_fault()
If the page is going to be written to, __do_page needs to break COW.

However, the old page (before breaking COW) was never mapped mapped into
the current pte (__do_fault is only called when the pte is not present),
so vmscan can't have marked the old page as PageMlocked due to being
mapped in __do_fault's VMA.  Therefore, __do_fault() does not need to
worry about clearing PageMlocked() on the old page.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@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>
2011-02-11 16:12:20 -08:00
Michel Lespinasse
e15f8c01af mlock: fix race when munlocking pages in do_wp_page()
vmscan can lazily find pages that are mapped within VM_LOCKED vmas, and
set the PageMlocked bit on these pages, transfering them onto the
unevictable list.  When do_wp_page() breaks COW within a VM_LOCKED vma,
it may need to clear PageMlocked on the old page and set it on the new
page instead.

This change fixes an issue where do_wp_page() was clearing PageMlocked
on the old page while the pte was still pointing to it (as well as
rmap).  Therefore, we were not protected against vmscan immediately
transfering the old page back onto the unevictable list.  This could
cause pages to get stranded there forever.

I propose to move the corresponding code to the end of do_wp_page(),
after the pte (and rmap) have been pointed to the new page.
Additionally, we can use munlock_vma_page() instead of
clear_page_mlock(), so that the old page stays mlocked if there are
still other VM_LOCKED vmas mapping it.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@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>
2011-02-11 16:12:20 -08:00
Yinghai Lu
e6d2e2b2b1 memblock: don't adjust size in memblock_find_base()
While applying patch to use memblock to find aperture for 64bit x86.
Ingo found system with 1g + force_iommu

> No AGP bridge found
> Node 0: aperture @ 38000000 size 32 MB
> Aperture pointing to e820 RAM. Ignoring.
> Your BIOS doesn't leave a aperture memory hole
> Please enable the IOMMU option in the BIOS setup
> This costs you 64 MB of RAM
> Cannot allocate aperture memory hole (0,65536K)

the corresponding code:

	addr = memblock_find_in_range(0, 1ULL<<32, aper_size, 512ULL<<20);
	if (addr == MEMBLOCK_ERROR || addr + aper_size > 0xffffffff) {
		printk(KERN_ERR
			"Cannot allocate aperture memory hole (%lx,%uK)\n",
				addr, aper_size>>10);
		return 0;
	}
	memblock_x86_reserve_range(addr, addr + aper_size, "aperture64")

fails because memblock core code align the size with 512M.  That could
make size way too big.

So don't align the size in that case.

actually __memblock_alloc_base, the another caller already align that
before calling that function.

BTW. x86 does not use __memblock_alloc_base...

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-11 16:12:20 -08:00
Soren Hansen
de1f016f88 nbd: remove module-level ioctl mutex
Commit 2a48fc0ab2 ("block: autoconvert trivial BKL users to private
mutex") replaced uses of the BKL in the nbd driver with mutex
operations.  Since then, I've been been seeing these lock ups:

 INFO: task qemu-nbd:16115 blocked for more than 120 seconds.
 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
 qemu-nbd      D 0000000000000001     0 16115  16114 0x00000004
  ffff88007d775d98 0000000000000082 ffff88007d775fd8 ffff88007d774000
  0000000000013a80 ffff8800020347e0 ffff88007d775fd8 0000000000013a80
  ffff880133730000 ffff880002034440 ffffea0004333db8 ffffffffa071c020
 Call Trace:
  [<ffffffff815b9997>] __mutex_lock_slowpath+0xf7/0x180
  [<ffffffff815b93eb>] mutex_lock+0x2b/0x50
  [<ffffffffa071a21c>] nbd_ioctl+0x6c/0x1c0 [nbd]
  [<ffffffff812cb970>] blkdev_ioctl+0x230/0x730
  [<ffffffff811967a1>] block_ioctl+0x41/0x50
  [<ffffffff81175c03>] do_vfs_ioctl+0x93/0x370
  [<ffffffff81175f61>] sys_ioctl+0x81/0xa0
  [<ffffffff8100c0c2>] system_call_fastpath+0x16/0x1b

Instrumenting the nbd module's ioctl handler with some extra logging
clearly shows the NBD_DO_IT ioctl being invoked which is a long-lived
ioctl in the sense that it doesn't return until another ioctl asks the
driver to disconnect.  However, that other ioctl blocks, waiting for the
module-level mutex that replaced the BKL, and then we're stuck.

This patch removes the module-level mutex altogether.  It's clearly
wrong, and as far as I can see, it's entirely unnecessary, since the nbd
driver maintains per-device mutexes, and I don't see anything that would
require a module-level (or kernel-level, for that matter) mutex.

Signed-off-by: Soren Hansen <soren@linux2go.dk>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Paul Clements <paul.clements@steeleye.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@kernel.org>		[2.6.37.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-11 16:12:20 -08:00
Alexander Strakh
24a6f5b858 drivers/rtc/rtc-proc.c: add module_put on error path in rtc_proc_open()
In file drivers/rtc/rtc-proc.c seq_open() can return -ENOMEM.

 86        if (!try_module_get(THIS_MODULE))
 87                return -ENODEV;
 88
 89        return single_open(file, rtc_proc_show, rtc);

In this case before exiting (line 89) from rtc_proc_open the
module_put(THIS_MODULE) must be called.

Found by Linux Device Drivers Verification Project

Signed-off-by: Alexander Strakh <strakh@ispras.ru>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-11 16:12:20 -08:00
Roland Stigge
6e20fb1805 drivers/gpio/pca953x.c: add a mutex to fix race condition
Add a mutex to register communication and handling.  Without the mutex,
GPIOs didn't switch as expected when toggled in a fast sequence of
status changes of multiple outputs.

Signed-off-by: Roland Stigge <stigge@antcom.de>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Marc Zyngier <maz@misterjones.org>
Cc: Ben Gardner <bgardner@wabtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-11 16:12:20 -08:00
Tejun Heo
01e05e9a90 ptrace: use safer wake up on ptrace_detach()
The wake_up_process() call in ptrace_detach() is spurious and not
interlocked with the tracee state.  IOW, the tracee could be running or
sleeping in any place in the kernel by the time wake_up_process() is
called.  This can lead to the tracee waking up unexpectedly which can be
dangerous.

The wake_up is spurious and should be removed but for now reduce its
toxicity by only waking up if the tracee is in TRACED or STOPPED state.

This bug can possibly be used as an attack vector.  I don't think it
will take too much effort to come up with an attack which triggers oops
somewhere.  Most sleeps are wrapped in condition test loops and should
be safe but we have quite a number of places where sleep and wakeup
conditions are expected to be interlocked.  Although the window of
opportunity is tiny, ptrace can be used by non-privileged users and with
some loading the window can definitely be extended and exploited.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-11 16:12:19 -08:00
Boaz Harrosh
d863b50ab0 vfs: call rcu_barrier after ->kill_sb()
In commit fa0d7e3de6 ("fs: icache RCU free inodes"), we use rcu free
inode instead of freeing the inode directly.  It causes a crash when we
rmmod immediately after we umount the volume[1].

So we need to call rcu_barrier after we kill_sb so that the inode is
freed before we do rmmod.  The idea is inspired by Aneesh Kumar.
rcu_barrier will wait for all callbacks to end before preceding.  The
original patch was done by Tao Ma, but synchronize_rcu() is not enough
here.

1. http://marc.info/?l=linux-fsdevel&m=129680863330185&w=2

Tested-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-11 16:12:19 -08:00
Linus Torvalds
2dab597441 Fix possible filp_cachep memory corruption
In commit 31e6b01f41 ("fs: rcu-walk for path lookup") we started doing
path lookup using RCU, which then falls back to a careful non-RCU lookup
in case of problems (LOOKUP_REVAL).  So do_filp_open() has this "re-do
the lookup carefully" looping case.

However, that means that we must not release the open-intent file data
if we are going to loop around and use it once more!

Fix this by moving the release of the open-intent data to the function
that allocates it (do_filp_open() itself) rather than the helper
functions that can get called multiple times (finish_open() and
do_last()).  This makes the logic for the lifetime of that field much
more obvious, and avoids the possible double free.

Reported-by: J. R. Okajima <hooanon05@yahoo.co.jp>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-11 15:53:38 -08:00
Russell King
e3329cba82 Merge branch 'fix' of git://git.kernel.org/pub/scm/linux/kernel/git/ycmiao/pxa-linux-2.6 into fixes 2011-02-11 22:56:19 +00:00
Will Deacon
66e1cfe6d5 ARM: 6657/1: hw_breakpoint: fix ptrace breakpoint advertising on unsupported arch
The ptrace debug information register was advertising breakpoint and
watchpoint resources for unsupported debug architectures. This meant
that setting breakpoints on these architectures would appear to succeed,
although they would never fire in reality.

This patch fixes the breakpoint slot probing so that it returns 0 when
running on an unsupported debug architecture.

Reported-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-11 22:54:48 +00:00
Will Deacon
ed19b739c5 ARM: 6656/1: hw_breakpoint: avoid UNPREDICTABLE behaviour when reading DBGDSCR
Reading baseline CP14 registers, other than DBGDIDR, when the OS Lock
is set leads to UNPREDICTABLE behaviour.

This patch ensures that we clear the OS lock before accessing anything
other than the DBGDIDR, thereby avoiding this behaviour.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-11 22:54:47 +00:00
Dmitry Eremin-Solenikov
34cd2d38db ARM: 6658/1: collie: do actually pass locomo_info to locomo driver
locomo_info isn't actually used as a platform_data on collie platform:
 arm/mach-sa1100/collie.c:237: warning: ‘locomo_info’ defined but not used

So locomo driver doesn't setup IRQs correctly. Pass locomo_info to the
driver.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-11 22:53:40 +00:00