Commit Graph

209791 Commits

Author SHA1 Message Date
Jens Axboe
6d0aed7a38 do_mounts: only enable PARTUUID for CONFIG_BLOCK
When CONFIG_BLOCK is not enabled:

init/do_mounts.c:71: error: implicit declaration of function 'dev_to_part'
init/do_mounts.c:71: warning: initialization makes pointer from integer without a cast
init/do_mounts.c:73: error: dereferencing pointer to incomplete type
init/do_mounts.c:76: error: dereferencing pointer to incomplete type
init/do_mounts.c:76: error: dereferencing pointer to incomplete type
init/do_mounts.c:102: error: implicit declaration of function 'part_pack_uuid'
init/do_mounts.c:104: error: 'block_class' undeclared (first use in this function)

Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-17 10:00:46 +02:00
Signed-off-by: Jan Kara
01ea50638b block: Fix race during disk initialization
When a new disk is being discovered, add_disk() first ties the bdev to gendisk
(via register_disk()->blkdev_get()) and only after that calls
bdi_register_bdev(). Because register_disk() also creates disk's kobject, it
can happen that userspace manages to open and modify the device's data (or
inode) before its BDI is properly initialized leading to a warning in
__mark_inode_dirty().

Fix the problem by registering BDI early enough.

This patch addresses https://bugzilla.kernel.org/show_bug.cgi?id=16312

Cc: stable@kernel.org
Reported-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-16 20:36:36 +02:00
Vivek Goyal
2786c4e5e5 blkio: Documentation Update
o Documentation update

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-16 08:45:03 +02:00
Vivek Goyal
8e89d13f4e blkio: Implementation of IOPS limit logic
o core logic of implementing IOPS throttling.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-16 08:44:00 +02:00
Vivek Goyal
7702e8f45b blk-cgroup: cgroup changes for IOPS limit support
o cgroup changes for IOPS throttling rules.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-16 08:42:58 +02:00
Vivek Goyal
e43473b7f2 blkio: Core implementation of throttle policy
o Actual implementation of throttling policy in block layer. Currently it
  implements READ and WRITE bytes per second throttling logic. IOPS throttling
  comes in later patches.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-16 08:42:52 +02:00
Vivek Goyal
4c9eefa16c blk-cgroup: Introduce cgroup changes for throttling policy
o cgroup chagnes for throttle policy.

o Introduces READ and WRITE bytes per second throttling rules.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-16 08:42:12 +02:00
Vivek Goyal
062a644d61 blk-cgroup: Prepare the base for supporting more than one IO control policies
o This patch prepares the base for introducing new IO control policies.
  Currently all the code is written knowing there is only one policy
  and that is proportional bandwidth. Creating infrastructure for newer
  policies to come in.

o Also there were many functions which were generated using macro. It was
  very confusing. Got rid of those.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-16 08:42:04 +02:00
Vivek Goyal
af41d7bd9b blk-cgroup: Kill the header printed at the start of blkio.weight_device file
o Kill extra "dev weight" header which is printed when somebody reads
  blkio.weight_device file. This really seems to be out of convention. No other
  blkio files are printing any header at the start of file. I think it is ok
  to just print values and how to interpret values should be part of
  documentation.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-16 08:40:42 +02:00
Jens Axboe
38b6f45a97 core: match_dev_by_uuid() should not be marked __init
It is also called outside the scope of init functions. Stephen
reports:

WARNING: init/mounts.o(.text+0x21a): Section mismatch in reference from the function name_to_dev_t() to the function .init.text:match_dev_by_uuid()
The function name_to_dev_t() references
the function __init match_dev_by_uuid().
This is often because name_to_dev_t lacks a __init
annotation or the annotation of match_dev_by_uuid is wrong.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-16 08:33:54 +02:00
Namhyung Kim
2610a25406 sg: fix a warning in blk_rq_aligned() call
2nd argument of blk_rq_aligned() has changed to 'unsigned long' by
the previous commit 'block: fix an address space warning in blk-map.c'.
That commit neglected to update a user of that function.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-16 08:25:45 +02:00
Will Drewry
b5af921ec0 init: add support for root devices specified by partition UUID
This is the third patch in a series which adds support for
storing partition metadata, optionally, off of the hd_struct.

One major use for that data is being able to resolve partition
by other identities than just the index on a block device.  Device
enumeration varies by platform and there's a benefit to being able
to use something like EFI GPT's GUIDs to determine the correct
block device and partition to mount as the root.

This change adds that support to root= by adding support for
the following syntax:

  root=PARTUUID=hex-uuid

Signed-off-by: Will Drewry <wad@chromium.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 16:14:03 +02:00
Will Drewry
eec7ecfede genhd, efi: add efi partition metadata to hd_structs
This change extends the partition_meta_info structure to
support EFI GPT-specific metadata and ensures that data
is copied in on partition scanning.

Signed-off-by: Will Drewry <wad@chromium.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 16:13:28 +02:00
Will Drewry
6d1d8050b4 block, partition: add partition_meta_info to hd_struct
I'm reposting this patch series as v4 since there have been no additional
comments, and I cleaned up one extra bit of unneeded code (in 3/3). The patches
are against Linus's tree: 2bfc96a127
(2.6.36-rc3).

Would this patchset be suitable for inclusion in an mm branch?

This changes adds a partition_meta_info struct which itself contains a
union of structures that provide partition table specific metadata.

This change leaves the union empty. The subsequent patch includes an
implementation for CONFIG_EFI_PARTITION-based metadata.

Signed-off-by: Will Drewry <wad@chromium.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 16:13:18 +02:00
Namhyung Kim
144177991c block: fix an address space warning in blk-map.c
Change type of 2nd parameter of blk_rq_aligned() into unsigned long
and remove unnecessary casting. Now we can call it with 'uaddr'
instead of 'ubuf' in __blk_rq_map_user() so that it can remove
following warnings from sparse:

 block/blk-map.c:57:31: warning: incorrect type in argument 2 (different address spaces)
 block/blk-map.c:57:31:    expected void *addr
 block/blk-map.c:57:31:    got void [noderef] <asn:1>*ubuf

However blk_rq_map_kern() needs one more local variable to handle it.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 13:08:27 +02:00
San Mehat
8dcbdc742f block: block_dump: Add number of sectors to debug output
Signed-off-by: San Mehat <san@android.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-14 08:48:01 +02:00
Christof Schmitt
175b79f063 zfcp: Report scatter gather limit for DIX protection information
When sending DIX integrity segments with an I/O request, the
restriction for the maximum number of segments is still the same for
the zfcp hardware. Report the new sg_prot_tablesize for the SCSI host,
so that the number of integrity segments plus the number of data
segments is not larger than the hardware limit. This results in using
half of the hardware segments for integrity data and the other half
for regular data.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>
2010-09-10 20:50:40 +02:00
Martin K. Petersen
13f05c8d8e block/scsi: Provide a limit on the number of integrity segments
Some controllers have a hardware limit on the number of protection
information scatter-gather list segments they can handle.

Introduce a max_integrity_segments limit in the block layer and provide
a new scsi_host_template setting that allows HBA drivers to provide a
value suitable for the hardware.

Add support for honoring the integrity segment limit when merging both
bios and requests.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>
2010-09-10 20:50:10 +02:00
Martin K. Petersen
c8bf133682 Consolidate min_not_zero
We have several users of min_not_zero, each of them using their own
definition.  Move the define to kernel.h.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>
2010-09-10 20:07:38 +02:00
Linus Torvalds
76be97c1fc Linux 2.6.36-rc2 2010-08-22 17:43:29 -07:00
Linus Torvalds
3dc8d7f07e Merge branch 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: PIT: free irq source id in handling error path
  KVM: destroy workqueue on kvm_create_pit() failures
  KVM: fix poison overwritten caused by using wrong xstate size
2010-08-22 11:27:36 -07:00
Linus Torvalds
4238a417a9 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel: (58 commits)
  drm/i915,intel_agp: Add support for Sandybridge D0
  drm/i915: fix render pipe control notify on sandybridge
  agp/intel: set 40-bit dma mask on Sandybridge
  drm/i915: Remove the conflicting BUG_ON()
  drm/i915/suspend: s/IS_IRONLAKE/HAS_PCH_SPLIT/
  drm/i915/suspend: Flush register writes before busy-waiting.
  i915: disable DAC on Ironlake also when doing CRT load detection.
  drm/i915: wait for actual vblank, not just 20ms
  drm/i915: make sure eDP PLL is enabled at the right time
  drm/i915: fix VGA plane disable for Ironlake+
  drm/i915: eDP mode set sequence corrections
  drm/i915: add panel reset workaround
  drm/i915: Enable RC6 on Ironlake.
  drm/i915/sdvo: Only set is_lvds if we have a valid fixed mode.
  drm/i915: Set up a render context on Ironlake
  drm/i915 invalidate indirect state pointers at end of ring exec
  drm/i915: Wake-up wait_request() from elapsed hang-check (v2)
  drm/i915: Apply i830 errata for cursor alignment
  drm/i915: Only update i845/i865 CURBASE when disabled (v2)
  drm/i915: FBC is updated within set_base() so remove second call in mode_set()
  ...
2010-08-22 11:03:27 -07:00
Linus Torvalds
bc584c5107 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
  slab: fix object alignment
  slub: add missing __percpu markup in mm/slub_def.h
2010-08-22 10:08:52 -07:00
Linus Torvalds
a28e0852d4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2:
  nilfs2: wait for discard to finish
2010-08-22 09:44:47 -07:00
Zhenyu Wang
4fefe43562 drm/i915,intel_agp: Add support for Sandybridge D0
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2010-08-21 23:29:03 -07:00
Zhenyu Wang
3fdef0205e drm/i915: fix render pipe control notify on sandybridge
This one is missed in last pipe control fix for sandybridge,
that really unmask interrupt bit for notify in render engine IMR.

Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2010-08-21 23:28:54 -07:00
Zhenyu Wang
877fdacf82 agp/intel: set 40-bit dma mask on Sandybridge
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2010-08-21 23:24:50 -07:00
Chris Wilson
156dadc180 drm/i915: Remove the conflicting BUG_ON()
We now attempt to free "active" objects following a GPU hang as either
the GPU will be reset or the hang is permenant. In either case, the GPU
writes will not be flushed to main memory and it should be safe to
return that memory back to the system.

The BUG_ON(active) is thus overkill and can erroneously fire after a
EIO.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>
2010-08-21 23:21:13 -07:00
Chris Wilson
90eb77baae drm/i915/suspend: s/IS_IRONLAKE/HAS_PCH_SPLIT/
For the shared paths on the next generation chipsets.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>
2010-08-21 23:20:21 -07:00
Chris Wilson
72bcb26909 drm/i915/suspend: Flush register writes before busy-waiting.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>
2010-08-21 23:20:17 -07:00
Dave Airlie
d5dd96cb28 i915: disable DAC on Ironlake also when doing CRT load detection.
Like on Sandybridge, disabling the DAC here when doing CRT load detect
avoids forever hangs waiting on the hardware.

test procedure on HP 2740p:
boot with no VGA plugged in, start X,
plug in VGA monitor (1280x1024)
chvt 3
machine hangs waiting forever.

Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2010-08-21 23:07:04 -07:00
Jesse Barnes
9d0498a2bf drm/i915: wait for actual vblank, not just 20ms
Waiting for a hard coded 20ms isn't always enough to make sure a vblank
period has actually occurred, so add code to make sure we really have
passed through a vblank period (or that the pipe is off when disabling).

This prevents problems with mode setting and link training, and seems to
fix a bug like https://bugs.freedesktop.org/show_bug.cgi?id=29278, but
on an HP 8440p instead.  Hopefully also fixes
https://bugs.freedesktop.org/show_bug.cgi?id=29141.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
2010-08-21 22:59:23 -07:00
Arjan van de Ven
e36c886a0f workqueue: Add basic tracepoints to track workqueue execution
With the introduction of the new unified work queue thread pools,
we lost one feature: It's no longer possible to know which worker
is causing the CPU to wake out of idle. The result is that PowerTOP
now reports a lot of "kworker/a:b" instead of more readable results.

This patch adds a pair of tracepoints to the new workqueue code,
similar in style to the timer/hrtimer tracepoints.

With this pair of tracepoints, the next PowerTOP can correctly
report which work item caused the wakeup (and how long it took):

Interrupt (43)            i915      time   3.51ms    wakeups 141
Work      ieee80211_iface_work      time   0.81ms    wakeups  29
Work              do_dbs_timer      time   0.55ms    wakeups  24
Process                   Xorg      time  21.36ms    wakeups   4
Timer    sched_rt_period_timer      time   0.01ms    wakeups   1

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-21 13:19:37 -07:00
Linus Torvalds
69b26c7ad0 Merge git://git.infradead.org/mtd-2.6
* git://git.infradead.org/mtd-2.6:
  mtd: nand: Fix probe of Samsung NAND chips
  mtd: nand: Fix regression in BBM detection
  pxa3xx: fix ns2cycle equation
2010-08-21 12:47:05 -07:00
Samuel Thibault
ddb0c5a689 Replace Configure with Enable in description of MAXSMP
The "Configure" word tends to make user believe they have to say 'yes'
to be able to choose the number of procs/nodes.  "Enable" should be
unambiguous enough.

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-21 12:38:58 -07:00
Linus Torvalds
0e8e50e20c mm: make stack guard page logic use vm_prev pointer
Like the mlock() change previously, this makes the stack guard check
code use vma->vm_prev to see what the mapping below the current stack
is, rather than have to look it up with find_vma().

Also, accept an abutting stack segment, since that happens naturally if
you split the stack with mlock or mprotect.

Tested-by: Ian Campbell <ijc@hellion.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-21 08:50:00 -07:00
Linus Torvalds
7798330ac8 mm: make the mlock() stack guard page checks stricter
If we've split the stack vma, only the lowest one has the guard page.
Now that we have a doubly linked list of vma's, checking this is trivial.

Tested-by: Ian Campbell <ijc@hellion.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-21 08:49:50 -07:00
Linus Torvalds
297c5eee37 mm: make the vma list be doubly linked
It's a really simple list, and several of the users want to go backwards
in it to find the previous vma.  So rather than have to look up the
previous entry with 'find_vma_prev()' or something similar, just make it
doubly linked instead.

Tested-by: Ian Campbell <ijc@hellion.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-21 08:49:21 -07:00
Tilman Sauerbeck
cfe3fdadb1 mtd: nand: Fix probe of Samsung NAND chips
Apparently, the check for a 6-byte ID string introduced by commit
426c457a32 ("mtd: nand: extend NAND flash
detection to new MLC chips") is NOT sufficient to determine whether or
not a Samsung chip uses their new MLC detection scheme or the old,
standard scheme. This adds a condition to check cell type.

Signed-off-by: Tilman Sauerbeck <tilman@code-monkey.de>
Signed-off-by: Brian Norris <norris@broadcom.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: stable@kernel.org
2010-08-20 22:26:20 +01:00
Linus Torvalds
36423a5ed5 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, apic: Fix apic=debug boot crash
  x86, hotplug: Serialize CPU hotplug to avoid bringup concurrency issues
  x86-32: Fix dummy trampoline-related inline stubs
  x86-32: Separate 1:1 pagetables from swapper_pg_dir
  x86, cpu: Fix regression in AMD errata checking code
2010-08-20 14:25:08 -07:00
Stephen Rothwell
f6143a9b73 Documentation: fix ozlabs.org mailing list address
This list moved to lists.ozlabs.org quite some time ago.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-20 09:55:41 -07:00
Stephen Rothwell
a4724ed6f0 MAINTAINERS: Fix ozlabs.org mailing list addresses
All these lists moved to lists.ozlabs.org quite a while ago.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-20 09:55:41 -07:00
Stefan Richter
1ee4168057 Documentation: kernel-locking: mutex_trylock cannot be used in interrupt context
Chapter 6 is right about mutex_trylock, but chapter 10 wasn't.  This error
was introduced during semaphore-to-mutex conversion of the Unreliable
guide.  :-)

If user context which performs mutex_lock() or mutex_trylock() is
preempted by interrupt context which performs mutex_trylock() on the same
mutex instance, a deadlock occurs.  This is because these functions do not
disable local IRQs when they operate on mutex->wait_lock.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-20 09:34:56 -07:00
Andrew Morton
626115cda9 drivers/scsi/qla4xxx: fix build
gcc-4.0.2:

  drivers/scsi/qla4xxx/ql4_os.c: In function 'qla4_8xxx_error_recovery':
  drivers/scsi/qla4xxx/ql4_glbl.h:135: sorry, unimplemented: inlining failed in call to 'qla4_8xxx_set_drv_active': function body not available
  drivers/scsi/qla4xxx/ql4_os.c:2377: sorry, unimplemented: called from here
  drivers/scsi/qla4xxx/ql4_glbl.h:135: sorry, unimplemented: inlining failed in call to 'qla4_8xxx_set_drv_active': function body not available
  drivers/scsi/qla4xxx/ql4_os.c:2393: sorry, unimplemented: called from here

Cc: Ravi Anand <ravi.anand@qlogic.com>
Cc: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-20 09:34:56 -07:00
Miklos Szeredi
f3c072ad72 uml: fix compile error in dma_get_cache_alignment()
Fix uml compile error:

  include/linux/dma-mapping.h:145: error: redefinition of 'dma_get_cache_alignment'
  arch/um/include/asm/dma-mapping.h:99: note: previous definition of 'dma_get_cache_alignment' was here

Introduced by commit 4565f0170d ("dma-mapping: unify
dma_get_cache_alignment implementations")

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-20 09:34:55 -07:00
KOSAKI Motohiro
8d6c83f0ba oom: __task_cred() need rcu_read_lock()
dump_tasks() needs to hold the RCU read lock around its access of the
target task's UID.  To this end it should use task_uid() as it only needs
that one thing from the creds.

The fact that dump_tasks() holds tasklist_lock is insufficient to prevent the
target process replacing its credentials on another CPU.

Then, this patch change to call rcu_read_lock() explicitly.

	===================================================
	[ INFO: suspicious rcu_dereference_check() usage. ]
	---------------------------------------------------
	mm/oom_kill.c:410 invoked rcu_dereference_check() without protection!

	other info that might help us debug this:

	rcu_scheduler_active = 1, debug_locks = 1
	4 locks held by kworker/1:2/651:
	 #0:  (events){+.+.+.}, at: [<ffffffff8106aae7>]
	process_one_work+0x137/0x4a0
	 #1:  (moom_work){+.+...}, at: [<ffffffff8106aae7>]
	process_one_work+0x137/0x4a0
	 #2:  (tasklist_lock){.+.+..}, at: [<ffffffff810fafd4>]
	out_of_memory+0x164/0x3f0
	 #3:  (&(&p->alloc_lock)->rlock){+.+...}, at: [<ffffffff810fa48e>]
	find_lock_task_mm+0x2e/0x70

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-20 09:34:55 -07:00
KOSAKI Motohiro
b52723c560 oom: fix tasklist_lock leak
Commit 0aad4b3124 ("oom: fold __out_of_memory into out_of_memory")
introduced a tasklist_lock leak.  Then it caused following obvious
danger warnings and panic.

    ================================================
    [ BUG: lock held when returning to user space! ]
    ------------------------------------------------
    rsyslogd/1422 is leaving the kernel with locks still held!
    1 lock held by rsyslogd/1422:
     #0:  (tasklist_lock){.+.+.+}, at: [<ffffffff810faf64>] out_of_memory+0x164/0x3f0
    BUG: scheduling while atomic: rsyslogd/1422/0x00000002
    INFO: lockdep is turned off.

This patch fixes it.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-20 09:34:55 -07:00
KOSAKI Motohiro
be71cf2202 oom: fix NULL pointer dereference
Commit b940fd7035 ("oom: remove unnecessary code and cleanup") added an
unnecessary NULL pointer dereference.  remove it.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-20 09:34:55 -07:00
Kyungmin Park
f522886e20 drivers/mmc/host/sdhci-s3c.c: use the correct mutex and card detect function
There's some merge problem between sdhic core and sdhci-s3c host.  After
mutex is changed to spinlock.  It needs to use use spin lock functions and
use the correct card detection function.

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-20 09:34:55 -07:00
Kyungmin Park
5193250168 sdhci: add no hi-speed bit quirk support
Some SDHCI controllers like s5pc110 don't have an HISPD bit in the HOSTCTL
register.

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-20 09:34:55 -07:00