Commit Graph

322559 Commits

Author SHA1 Message Date
Hans Verkuil
ed45ce2cc0 [media] v4l2-subdev: add support for the new edid ioctls
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-13 16:07:24 -03:00
Hans Verkuil
1248c7cb66 [media] V4L2 spec: document the new DV controls and ioctls
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-13 16:07:02 -03:00
Hans Verkuil
777f4f85b7 [media] v4l2 core: add the missing pieces to support DVI/HDMI/DisplayPort
These new controls and two new ioctls make it possible to properly support
VGA, DVI-A/D/I, HDMI and DisplayPort connectors. All these controls and the
ioctls are all at the sub-device level. They are meant for V4L2 bridge/platform
drivers or to be accessed on embedded systems through /dev/v4l-subdev* device
nodes.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-13 16:05:27 -03:00
Antti Palosaari
faedc36377 [media] dvb-usb: remove unused files
Those files were left from dvb-usb-v2 development as I have made
mistake during rebase operation.

Reported-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-13 13:37:36 -03:00
Antti Palosaari
7fa8694acf [media] dvb_usb_v2: use ratelimited debugs where appropriate
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-13 13:37:09 -03:00
Mauro Carvalho Chehab
64cbeb2818 [media] au0828, cx231xx: remove dependency for DVB_CAPTURE_DRIVERS
This symbol got removed by menu reorganization; just depending on
DVB_CORE is enough.

Reported-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-12 08:13:13 -03:00
Alexey Khoroshilov
f4e4a67a37 [media] ddbridge: fix error handling in module_init_ddbridge()
If pci_register_driver() failed, resources allocated in
ddb_class_create() are leaked. The patch fixes it
as well as it replaces -1 with correct error code
in ddb_class_create().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-11 15:29:00 -03:00
Anton Nurkin
4b83a7a753 [media] cx23885: fix pointer to structure for CAM
Fixes problem with CAM, when  after re-iinitialization
CAM used old pointer to structure.

Signed-off-by: Anton Nurkin <ptqa@netup.ru>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-10 11:53:50 -03:00
Antti Palosaari
0a23dc24cd [media] rtl2832: remove dummy callback implementations
Let the dvb-frontend return -ENOTTY for those unimplemented IOCTLs.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-10 11:31:59 -03:00
Antti Palosaari
3a35c00b04 [media] DocBook: update ioctl error codes
ENOTTY is now returned for unimplemented ioctl by dvb-frontend.
Old EOPNOTSUPP & ENOSYS could be still returned by some drivers
as well as other "non standard" error codes.

EAGAIN is returned in case of device is in state where it cannot
perform requested operation. This is for example sleep and statistics
are queried. Quick check for few demodulator drivers reveals there is
a lot of different error codes used in such case currently, few to
mention still: EOPNOTSUPP, ENOSYS, EAGAIN ... Lets try harmonize.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-10 11:28:50 -03:00
Antti Palosaari
177ffe506c [media] dvb_frontend: return -ENOTTY for unimplement IOCTL
Earlier it was returning -EOPNOTSUPP.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-10 11:14:35 -03:00
Antti Palosaari
36bdbc3fff [media] dvb_frontend: use Kernel dev_* logging
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-10 11:13:23 -03:00
Mauro Carvalho Chehab
1daae517b3 [media] move i2c files into drivers/media/i2c
Based on a patch from Sylvester Nawrocki

This fixes regression introduced with commmit cb7a01ac32,
"[media] move i2c files into drivers/media/i2c".

The linked order affect what drivers will be initialized first, when
they're built-in at Kernel. While there are macros that allow changing
the init order, like subsys_initcall(), late_initcall() & friends,
when all drivers  linked belong to the same subsystem, it is easier
to change the order at the Makefile.

All I2C modules must be linked before any drivers that actually use it,
in order to ensure proper module initialization order.

Also, the core drivers should be initialized before the drivers that use
them.

This patch reorders the drivers init, in order to fulfill the above
requirements.

Reported-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Acked-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-06 18:42:54 -03:00
Mauro Carvalho Chehab
79e8c7bebb Linux 3.6-rc3
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Merge tag 'v3.6-rc3' into staging/for_v3.7

Linux 3.6-rc3

* tag 'v3.6-rc3': (764 commits)
  Linux 3.6-rc3
  task_work: add a scheduling point in task_work_run()
  fs: fix fs/namei.c kernel-doc warnings
  eventpoll: use-after-possible-free in epoll_create1()
  vfio: grab vfio_device reference *before* exposing the sucker via fd_install()
  vfio: get rid of vfio_device_put()/vfio_group_get_device* races
  vfio: get rid of open-coding kref_put_mutex
  introduce kref_put_mutex()
  vfio: don't dereference after kfree...
  fbcon: fix race condition between console lock and cursor timer (v1.1)
  mm: compaction: Abort async compaction if locks are contended or taking too long
  mm: have order > 0 compaction start near a pageblock with free pages
  rapidio/tsi721: fix unused variable compiler warning
  rapidio/tsi721: fix inbound doorbell interrupt handling
  drivers/rtc/rtc-rs5c348.c: fix hour decoding in 12-hour mode
  mm: correct page->pfmemalloc to fix deactivate_slab regression
  drivers/rtc/rtc-pcf2123.c: initialize dynamic sysfs attributes
  mm/compaction.c: fix deferring compaction mistake
  drivers/misc/sgi-xp/xpc_uv.c: SGI XPC fails to load when cpu 0 is out of IRQ resources
  string: do not export memweight() to userspace
  ...
2012-08-24 11:25:10 -03:00
Linus Torvalds
fea7a08acb Linux 3.6-rc3 2012-08-22 13:29:06 -07:00
Linus Torvalds
4ff63e47f7 Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
 "Intel: edid fixes, power consumption fix, s/r fix, haswell fix

  Radeon: BIOS loading fixes for UEFI and Thunderbolt machines, better
  MSAA validation, lockup timeout fixes, modesetting fixes

  One udl dpms fix, one vmwgfx fix, a couple of trivial core changes.

  There is an export added to ACPI as part of the radeon bios fixes.

  I've also included the fbcon flashing cursor vs deinit race fix, that
  seems the simplest place to start"

Trivial conflict in drivers/video/console/fbcon.c due to me having
already applied the fbcon flashing cursor vs deinit race fix, and Dave
had added a comment in there too.

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (22 commits)
  fbcon: fix race condition between console lock and cursor timer (v1.1)
  drm: Add missing static storage class specifiers in drm_proc.c file
  drm/udl: dpms off the crtc when disabled.
  drm: Remove two unused fields from struct drm_display_mode
  drm: stop vmgfx driver explosion
  drm/radeon/ss: use num_crtc rather than hardcoded 6
  Revert "drm/radeon: fix bo creation retry path"
  drm/i915: use hsw rps tuning values everywhere on gen6+
  drm/radeon: split ATRM support out from the ATPX handler (v3)
  drm/radeon: convert radeon vfct code to use acpi_get_table_with_size
  ACPI: export symbol acpi_get_table_with_size
  drm/radeon: implement ACPI VFCT vbios fetch (v3)
  drm/radeon/kms: extend the Fujitsu D3003-S2 board connector quirk to cover later silicon stepping
  drm/radeon: fix checking of MSAA renderbuffers on r600-r700
  drm/radeon: allow CMASK and FMASK in the CS checker on r600-r700
  drm/radeon: init lockup timeout on ring init
  drm/radeon: avoid turning off spread spectrum for used pll
  drm/i915: fall back to bit-banging if GMBUS fails in CRT EDID reads
  drm/i915: extract connector update from intel_ddc_get_modes() for reuse
  drm/i915: fix hsw uncached pte
  ...
2012-08-22 10:45:13 -07:00
Linus Torvalds
0923699436 Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target fixes from Nicholas Bellinger:
 "The executive summary includes:

   - Post-merge review comments for tcm_vhost (MST + nab)
   - Avoid debugging overhead when not debugging for tcm-fc(FCoE) (MDR)
   - Fix NULL pointer dereference bug on alloc_page failulre (Yi Zou)
   - Fix REPORT_LUNs regression bug with pSCSI export (AlexE + nab)
   - Fix regression bug with handling of zero-length data CDBs (nab)
   - Fix vhost_scsi_target structure alignment (MST)

  Thanks again to everyone who contributed a bugfix patch, gave review
  feedback on tcm_vhost code, and/or reported a bug during their own
  testing over the last weeks.

  There is one other outstanding bug reported by Roland recently related
  to SCSI transfer length overflow handling, for which the current
  proposed bugfix has been left in queue pending further testing with
  other non iscsi-target based fabric drivers.

  As the patch is verified with loopback (local SGL memory from SCSI
  LLD) + tcm_qla2xxx (TCM allocated SGL memory mapped to PCI HW) fabric
  ports, it will be included into the next 3.6-rc-fixes PULL request."

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  target: Remove unused se_cmd.cmd_spdtl
  tcm_fc: rcu_deref outside rcu lock/unlock section
  tcm_vhost: Fix vhost_scsi_target structure alignment
  target: Fix regression bug with handling of zero-length data CDBs
  target/pscsi: Fix bug with REPORT_LUNs handling for SCSI passthrough
  tcm_vhost: Change vhost_scsi_target->vhost_wwpn to char *
  target: fix NULL pointer dereference bug alloc_page() fails to get memory
  tcm_fc: Avoid debug overhead when not debugging
  tcm_vhost: Post-merge review changes requested by MST
  tcm_vhost: Fix incorrect IS_ERR() usage in vhost_scsi_map_iov_to_sgl
2012-08-22 10:42:30 -07:00
Linus Torvalds
2e2d8c93ae Merge branch 'i2c-embedded/for-current' of git://git.pengutronix.de/git/wsa/linux
Pull i2c-embedded fixes from Wolfram Sang:
 "Some bugfixes for the "embedded" part of the I2C subsystem.  The fixes
  affect mostly drivers which have been largely reworked lately and
  where regressions appeared."

* 'i2c-embedded/for-current' of git://git.pengutronix.de/git/wsa/linux:
  i2c: tegra: protect suspend/resume callbacks with CONFIG_PM_SLEEP
  i2c: diolan-u2c: Fix master_xfer return code
  I2C: OMAP: xfer: fix runtime PM get/put balance on error
  i2c: nomadik: Add default configuration into the Nomadik I2C driver
2012-08-22 10:41:36 -07:00
Linus Torvalds
fec3c03fb0 pwm: fixes for v3.6-rc3
These patches fix the Samsung PWM driver and perform some minor cleanups
 like fixing checkpatch and sparse warnings. Two redundant error messages
 are removed and the Kconfig help text for the PWM subsystem is made more
 descriptive.
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Merge tag 'for-3.6-rc3' of git://gitorious.org/linux-pwm/linux-pwm

Pull pwm fixes from Thierry Reding:
 "These patches fix the Samsung PWM driver and perform some minor
  cleanups like fixing checkpatch and sparse warnings.

  Two redundant error messages are removed and the Kconfig help text for
  the PWM subsystem is made more descriptive."

* tag 'for-3.6-rc3' of git://gitorious.org/linux-pwm/linux-pwm:
  pwm: Improve Kconfig help text
  pwm: core: Fix coding style issues
  pwm: vt8500: Fix coding style issue
  pwm: Remove a redundant error message when devm_request_and_ioremap fails
  pwm: samsung: add missing device pointer to struct pwm_chip
  pwm: Add missing static storage class specifiers in core.c file
2012-08-22 10:27:12 -07:00
Linus Torvalds
f753c4ec15 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull ceph fixes from Sage Weil:
 "Jim's fix closes a narrow race introduced with the msgr changes.  One
  fix resolves problems with debugfs initialization that Yan found when
  multiple client instances are created (e.g., two clusters mounted, or
  rbd + cephfs), another one fixes problems with mounting a nonexistent
  server subdirectory, and the last one fixes a divide by zero error
  from unsanitized ioctl input that Dan Carpenter found."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  ceph: avoid divide by zero in __validate_layout()
  libceph: avoid truncation due to racing banners
  ceph: tolerate (and warn on) extraneous dentry from mds
  libceph: delay debugfs initialization until we learn global_id
2012-08-22 09:58:05 -07:00
Linus Torvalds
ad746be969 NFS client bugfixes for Linux 3.6
- NFSv3 mounts need to fail if the FSINFO rpc call fails
 - Ensure that the NFS commit cache gets torn down when we unload the
   NFS module.
 - Fix memory scribble issues when interrupting a LAYOUTGET rpc call
 - Fix NFSv4 legacy idmapper regressions
 - Fix issues with the NFSv4 getacl command
 - Fix a regression when using the legacy "mount -t nfs4"
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Merge tag 'nfs-for-3.6-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes from Trond Myklebust:
 - NFSv3 mounts need to fail if the FSINFO rpc call fails
 - Ensure that the NFS commit cache gets torn down when we unload the
   NFS module.
 - Fix memory scribble issues when interrupting a LAYOUTGET rpc call
 - Fix NFSv4 legacy idmapper regressions
 - Fix issues with the NFSv4 getacl command
 - Fix a regression when using the legacy "mount -t nfs4"

* tag 'nfs-for-3.6-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFSv3: Ensure that do_proc_get_root() reports errors correctly
  NFSv4: Ensure that nfs4_alloc_client cleans up on error.
  NFS: return -ENOKEY when the upcall fails to map the name
  NFS: Clear key construction data if the idmap upcall fails
  NFSv4: Don't use private xdr_stream fields in decode_getacl
  NFSv4: Fix the acl cache size calculation
  NFSv4: Fix pointer arithmetic in decode_getacl
  NFS: Alias the nfs module to nfs4
  NFS: Fix a regression when loading the NFS v4 module
  NFSv4.1: Remove a bogus BUG_ON() in nfs4_layoutreturn_done
  pnfs-obj: Better IO pattern in case of unaligned offset
  NFS41: add pg_layout_private to nfs_pageio_descriptor
  pnfs: nfs4_proc_layoutget returns void
  pnfs: defer release of pages in layoutget
  nfs: tear down caches in nfs_init_writepagecache when allocation fails
2012-08-22 09:57:25 -07:00
Linus Torvalds
467e9e51d0 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull assorted fixes - mostly vfs - from Al Viro:
 "Assorted fixes, with an unexpected detour into vfio refcounting logics
  (fell out when digging in an analog of eventpoll race in there)."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  task_work: add a scheduling point in task_work_run()
  fs: fix fs/namei.c kernel-doc warnings
  eventpoll: use-after-possible-free in epoll_create1()
  vfio: grab vfio_device reference *before* exposing the sucker via fd_install()
  vfio: get rid of vfio_device_put()/vfio_group_get_device* races
  vfio: get rid of open-coding kref_put_mutex
  introduce kref_put_mutex()
  vfio: don't dereference after kfree...
  mqueue: lift mnt_want_write() outside ->i_mutex, clean up a bit
2012-08-22 09:56:06 -07:00
Eric Dumazet
88ec2789d8 task_work: add a scheduling point in task_work_run()
It seems commit 4a9d4b02 (switch fput to task_work_add) reintroduced
the problem addressed in commit 944be0b2 (close_files(): add scheduling
point)

If a server process with a lot of files (say 2 million tcp sockets)
is killed, we can spend a lot of time in task_work_run() and trigger
a soft lockup.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-08-22 10:31:05 -04:00
Randy Dunlap
55852635a8 fs: fix fs/namei.c kernel-doc warnings
Fix kernel-doc warnings in fs/namei.c:

Warning(fs/namei.c:360): No description found for parameter 'inode'
Warning(fs/namei.c:672): No description found for parameter 'nd'

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc:	Alexander Viro <viro@zeniv.linux.org.uk>
Cc:	linux-fsdevel@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-08-22 10:30:10 -04:00
Al Viro
98022748f6 eventpoll: use-after-possible-free in epoll_create1()
As soon as we'd installed the file into descriptor table, it can
get closed by another thread.  Freeing ep in process...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-08-22 10:26:55 -04:00
Al Viro
31605debdf vfio: grab vfio_device reference *before* exposing the sucker via fd_install()
It's not critical (anymore) since another thread closing the file will block
on ->device_lock before it gets to dropping the final reference, but it's
definitely cleaner that way...

Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-08-22 10:26:42 -04:00
Al Viro
90b1253e41 vfio: get rid of vfio_device_put()/vfio_group_get_device* races
we really need to make sure that dropping the last reference happens
under the group->device_lock; otherwise a loop (under device_lock)
might find vfio_device instance that is being freed right now, has
already dropped the last reference and waits on device_lock to exclude
the sucker from the list.

Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-08-22 10:26:13 -04:00
Al Viro
6d2cd3ce81 vfio: get rid of open-coding kref_put_mutex
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-08-22 10:25:19 -04:00
Al Viro
8ad5db8a8d introduce kref_put_mutex()
equivalent of
	mutex_lock(mutex);
	if (!kref_put(kref, release))
		mutex_unlock(mutex);

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-08-22 10:24:41 -04:00
Al Viro
934ad4c235 vfio: don't dereference after kfree...
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-08-22 10:23:04 -04:00
Dave Airlie
d8636a2717 fbcon: fix race condition between console lock and cursor timer (v1.1)
So we've had a fair few reports of fbcon handover breakage between
efi/vesafb and i915 surface recently, so I dedicated a couple of
days to finding the problem.

Essentially the last thing we saw was the conflicting framebuffer
message and that was all.

So after much tracing with direct netconsole writes (printks
under console_lock not so useful), I think I found the race.

Thread A (driver load)    Thread B (timer thread)
  unbind_con_driver ->              |
  bind_con_driver ->                |
  vc->vc_sw->con_deinit ->          |
  fbcon_deinit ->                   |
  console_lock()                    |
      |                             |
      |                       fbcon_flashcursor timer fires
      |                       console_lock() <- blocked for A
      |
      |
fbcon_del_cursor_timer ->
  del_timer_sync
  (BOOM)

Of course because all of this is under the console lock,
we never see anything, also since we also just unbound the active
console guess what we never see anything.

Hopefully this fixes the problem for anyone seeing vesafb->kms
driver handoff.

v1.1: add comment suggestion from Alan.

Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-08-22 14:00:35 +10:00
Linus Torvalds
23dcfa61ba Merge branch 'akpm' (Andrew's patch-bomb)
Merge fixes from Andrew Morton.

Random drivers and some VM fixes.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (17 commits)
  mm: compaction: Abort async compaction if locks are contended or taking too long
  mm: have order > 0 compaction start near a pageblock with free pages
  rapidio/tsi721: fix unused variable compiler warning
  rapidio/tsi721: fix inbound doorbell interrupt handling
  drivers/rtc/rtc-rs5c348.c: fix hour decoding in 12-hour mode
  mm: correct page->pfmemalloc to fix deactivate_slab regression
  drivers/rtc/rtc-pcf2123.c: initialize dynamic sysfs attributes
  mm/compaction.c: fix deferring compaction mistake
  drivers/misc/sgi-xp/xpc_uv.c: SGI XPC fails to load when cpu 0 is out of IRQ resources
  string: do not export memweight() to userspace
  hugetlb: update hugetlbpage.txt
  checkpatch: add control statement test to SINGLE_STATEMENT_DO_WHILE_MACRO
  mm: hugetlbfs: correctly populate shared pmd
  cciss: fix incorrect scsi status reporting
  Documentation: update mount option in filesystem/vfat.txt
  mm: change nr_ptes BUG_ON to WARN_ON
  cs5535-clockevt: typo, it's MFGPT, not MFPGT
2012-08-21 17:22:22 -07:00
Linus Torvalds
a484147a52 Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media fixes from Mauro Carvalho Chehab:
 "For bug fixes, at soc_camera, si470x, uvcvideo, iguanaworks IR driver,
  radio_shark Kbuild fixes, and at the V4L2 core (radio fixes)."

* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  [media] media: soc_camera: don't clear pix->sizeimage in JPEG mode
  [media] media: mx2_camera: Fix clock handling for i.MX27
  [media] video: mx2_camera: Use clk_prepare_enable/clk_disable_unprepare
  [media] video: mx1_camera: Use clk_prepare_enable/clk_disable_unprepare
  [media] media: mx3_camera: buf_init() add buffer state check
  [media] radio-shark2: Only compile led support when CONFIG_LED_CLASS is set
  [media] radio-shark: Only compile led support when CONFIG_LED_CLASS is set
  [media] radio-shark*: Call cancel_work_sync from disconnect rather then release
  [media] radio-shark*: Remove work-around for dangling pointer in usb intfdata
  [media] Add USB dependency for IguanaWorks USB IR Transceiver
  [media] Add missing logging for rangelow/high of hwseek
  [media] VIDIOC_ENUM_FREQ_BANDS fix
  [media] mem2mem_testdev: fix querycap regression
  [media] si470x: v4l2-compliance fixes
  [media] DocBook: Remove a spurious character
  [media] uvcvideo: Reset the bytesused field when recycling an erroneous buffer
2012-08-21 16:54:38 -07:00
Linus Torvalds
8f8ba75ee2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking update from David Miller:
 "A couple weeks of bug fixing in there.  The largest chunk is all the
  broken crap Amerigo Wang found in the netpoll layer."

 1) netpoll and it's users has several serious bugs:
    a) uses GFP_KERNEL with locks held
    b) interfaces requiring interrupts disabled are called with them
       enabled
    c) and vice versa
    d) VLAN tag demuxing, as per all other RX packet input paths, is not
       applied

    All from Amerigo Wang.

 2) Hopefully cure the ipv4 mapped ipv6 address TCP early demux bugs for
    good, from Neal Cardwell.

 3) Unlike AF_UNIX, AF_PACKET sockets don't set a default credentials
    when the user doesn't specify one explicitly during sendmsg().
    Instead we attach an empty (zero) SCM credential block which is
    definitely not what we want.  Fix from Eric Dumazet.

 4) IPv6 illegally invokes netdevice notifiers with RCU lock held, fix
    from Ben Hutchings.

 5) inet_csk_route_child_sock() checks wrong inet options pointer, fix
    from Christoph Paasch.

 6) When AF_PACKET is used for transmit, packet loopback doesn't behave
    properly when a socket fanout is enabled, from Eric Leblond.

 7) On bluetooth l2cap channel create failure, we leak the socket, from
    Jaganath Kanakkassery.

 8) Fix all the netprio file handling bugs found by Al Viro, from John
    Fastabend.

 9) Several error return and NULL deref bug fixes in networking drivers
    from Julia Lawall.

10) A large smattering of struct padding et al.  kernel memory leaks to
    userspace found of Mathias Krause.

11) Conntrack expections in netfilter can access an uninitialized timer,
    fix from Pablo Neira Ayuso.

12) Several netfilter SIP tracker bug fixes from Patrick McHardy.

13) IPSEC ipv6 routes are not initialized correctly all the time,
    resulting in an OOPS in inet_putpeer().  Also from Patrick McHardy.

14) Bridging does rcu_dereference() outside of RCU protected area, from
    Stephen Hemminger.

15) Fix routing cache removal performance regression when looking up
    output routes that have a local destination.  From Zheng Yan.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (87 commits)
  af_netlink: force credentials passing [CVE-2012-3520]
  ipv4: fix ip header ident selection in __ip_make_skb()
  ipv4: Use newinet->inet_opt in inet_csk_route_child_sock()
  tcp: fix possible socket refcount problem
  net: tcp: move sk_rx_dst_set call after tcp_create_openreq_child()
  net/core/dev.c: fix kernel-doc warning
  netconsole: remove a redundant netconsole_target_put()
  net: ipv6: fix oops in inet_putpeer()
  net/stmmac: fix issue of clk_get for Loongson1B.
  caif: Do not dereference NULL in chnl_recv_cb()
  af_packet: don't emit packet on orig fanout group
  drivers/net/irda: fix error return code
  drivers/net/wan/dscc4.c: fix error return code
  drivers/net/wimax/i2400m/fw.c: fix error return code
  smsc75xx: add missing entry to MAINTAINERS
  net: qmi_wwan: new devices: UML290 and K5006-Z
  net: sh_eth: Add eth support for R8A7779 device
  netdev/phy: skip disabled mdio-mux nodes
  dt: introduce for_each_available_child_of_node, of_get_next_available_child
  net: netprio: fix cgrp create and write priomap race
  ...
2012-08-21 16:46:08 -07:00
Mel Gorman
c67fe3752a mm: compaction: Abort async compaction if locks are contended or taking too long
Jim Schutt reported a problem that pointed at compaction contending
heavily on locks.  The workload is straight-forward and in his own words;

	The systems in question have 24 SAS drives spread across 3 HBAs,
	running 24 Ceph OSD instances, one per drive.  FWIW these servers
	are dual-socket Intel 5675 Xeons w/48 GB memory.  I've got ~160
	Ceph Linux clients doing dd simultaneously to a Ceph file system
	backed by 12 of these servers.

Early in the test everything looks fine

  procs -------------------memory------------------ ---swap-- -----io---- --system-- -----cpu-------
   r  b       swpd       free       buff      cache   si   so    bi    bo   in   cs  us sy  id wa st
  31 15          0     287216        576   38606628    0    0     2  1158    2   14   1  3  95  0  0
  27 15          0     225288        576   38583384    0    0    18 2222016 203357 134876  11 56  17 15  0
  28 17          0     219256        576   38544736    0    0    11 2305932 203141 146296  11 49  23 17  0
   6 18          0     215596        576   38552872    0    0     7 2363207 215264 166502  12 45  22 20  0
  22 18          0     226984        576   38596404    0    0     3 2445741 223114 179527  12 43  23 22  0

and then it goes to pot

  procs -------------------memory------------------ ---swap-- -----io---- --system-- -----cpu-------
   r  b       swpd       free       buff      cache   si   so    bi    bo   in   cs  us sy  id wa st
  163  8          0     464308        576   36791368    0    0    11 22210  866  536   3 13  79  4  0
  207 14          0     917752        576   36181928    0    0   712 1345376 134598 47367   7 90   1  2  0
  123 12          0     685516        576   36296148    0    0   429 1386615 158494 60077   8 84   5  3  0
  123 12          0     598572        576   36333728    0    0  1107 1233281 147542 62351   7 84   5  4  0
  622  7          0     660768        576   36118264    0    0   557 1345548 151394 59353   7 85   4  3  0
  223 11          0     283960        576   36463868    0    0    46 1107160 121846 33006   6 93   1  1  0

Note that system CPU usage is very high blocks being written out has
dropped by 42%. He analysed this with perf and found

  perf record -g -a sleep 10
  perf report --sort symbol --call-graph fractal,5
    34.63%  [k] _raw_spin_lock_irqsave
            |
            |--97.30%-- isolate_freepages
            |          compaction_alloc
            |          unmap_and_move
            |          migrate_pages
            |          compact_zone
            |          compact_zone_order
            |          try_to_compact_pages
            |          __alloc_pages_direct_compact
            |          __alloc_pages_slowpath
            |          __alloc_pages_nodemask
            |          alloc_pages_vma
            |          do_huge_pmd_anonymous_page
            |          handle_mm_fault
            |          do_page_fault
            |          page_fault
            |          |
            |          |--87.39%-- skb_copy_datagram_iovec
            |          |          tcp_recvmsg
            |          |          inet_recvmsg
            |          |          sock_recvmsg
            |          |          sys_recvfrom
            |          |          system_call
            |          |          __recv
            |          |          |
            |          |           --100.00%-- (nil)
            |          |
            |           --12.61%-- memcpy
             --2.70%-- [...]

There was other data but primarily it is all showing that compaction is
contended heavily on the zone->lock and zone->lru_lock.

commit [b2eef8c0: mm: compaction: minimise the time IRQs are disabled
while isolating pages for migration] noted that it was possible for
migration to hold the lru_lock for an excessive amount of time. Very
broadly speaking this patch expands the concept.

This patch introduces compact_checklock_irqsave() to check if a lock
is contended or the process needs to be scheduled. If either condition
is true then async compaction is aborted and the caller is informed.
The page allocator will fail a THP allocation if compaction failed due
to contention. This patch also introduces compact_trylock_irqsave()
which will acquire the lock only if it is not contended and the process
does not need to schedule.

Reported-by: Jim Schutt <jaschut@sandia.gov>
Tested-by: Jim Schutt <jaschut@sandia.gov>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:03 -07:00
Mel Gorman
de74f1cc3b mm: have order > 0 compaction start near a pageblock with free pages
Commit 7db8889ab0 ("mm: have order > 0 compaction start off where it
left") introduced a caching mechanism to reduce the amount work the free
page scanner does in compaction.  However, it has a problem.  Consider
two process simultaneously scanning free pages

					    			C
	Process A		M     S     			F
			|---------------------------------------|
	Process B		M 	FS

	C is zone->compact_cached_free_pfn
	S is cc->start_pfree_pfn
	M is cc->migrate_pfn
	F is cc->free_pfn

In this diagram, Process A has just reached its migrate scanner, wrapped
around and updated compact_cached_free_pfn accordingly.

Simultaneously, Process B finishes isolating in a block and updates
compact_cached_free_pfn again to the location of its free scanner.

Process A moves to "end_of_zone - one_pageblock" and runs this check

                if (cc->order > 0 && (!cc->wrapped ||
                                      zone->compact_cached_free_pfn >
                                      cc->start_free_pfn))
                        pfn = min(pfn, zone->compact_cached_free_pfn);

compact_cached_free_pfn is above where it started so the free scanner
skips almost the entire space it should have scanned.  When there are
multiple processes compacting it can end in a situation where the entire
zone is not being scanned at all.  Further, it is possible for two
processes to ping-pong update to compact_cached_free_pfn which is just
random.

Overall, the end result wrecks allocation success rates.

There is not an obvious way around this problem without introducing new
locking and state so this patch takes a different approach.

First, it gets rid of the skip logic because it's not clear that it
matters if two free scanners happen to be in the same block but with
racing updates it's too easy for it to skip over blocks it should not.

Second, it updates compact_cached_free_pfn in a more limited set of
circumstances.

If a scanner has wrapped, it updates compact_cached_free_pfn to the end
	of the zone. When a wrapped scanner isolates a page, it updates
	compact_cached_free_pfn to point to the highest pageblock it
	can isolate pages from.

If a scanner has not wrapped when it has finished isolated pages it
	checks if compact_cached_free_pfn is pointing to the end of the
	zone. If so, the value is updated to point to the highest
	pageblock that pages were isolated from. This value will not
	be updated again until a free page scanner wraps and resets
	compact_cached_free_pfn.

This is not optimal and it can still race but the compact_cached_free_pfn
will be pointing to or very near a pageblock with free pages.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:03 -07:00
Alexandre Bounine
9a9a9a7ada rapidio/tsi721: fix unused variable compiler warning
Fix unused variable compiler warning when built with CONFIG_RAPIDIO_DEBUG
option off.

This patch is applicable to kernel versions starting from v3.2

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:03 -07:00
Alexandre Bounine
3670e7e12e rapidio/tsi721: fix inbound doorbell interrupt handling
Make sure that there is no doorbell messages left behind due to disabled
interrupts during inbound doorbell processing.

The most common case for this bug is loss of rionet JOIN messages in
systems with three or more rionet participants and MSI or MSI-X enabled.
As result, requests for packet transfers may finish with "destination
unreachable" error message.

This patch is applicable to kernel versions starting from v3.2.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:03 -07:00
Atsushi Nemoto
7dbfb315b2 drivers/rtc/rtc-rs5c348.c: fix hour decoding in 12-hour mode
Correct the offset by subtracting 20 from tm_hour before taking the
modulo 12.

[ "Why 20?" I hear you ask. Or at least I did.

  Here's the reason why: RS5C348_BIT_PM is 32, and is - stupidly -
  included in the RS5C348_HOURS_MASK define.  So it's really subtracting
  out that bit to get "hour+12".  But then because it does things modulo
  12, it needs to add the 12 in again afterwards anyway.

  This code is confused.  It would be much clearer if RS5C348_HOURS_MASK
  just didn't include the RS5C348_BIT_PM bit at all, then it wouldn't
  need to do the silly subtract either.

  Whatever. It's all just math, the end result is the same.   - Linus ]

Reported-by: James Nute <newten82@gmail.com>
Tested-by: James Nute <newten82@gmail.com>
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:03 -07:00
Alex Shi
b121186ab1 mm: correct page->pfmemalloc to fix deactivate_slab regression
Commit cfd19c5a9e ("mm: only set page->pfmemalloc when
ALLOC_NO_WATERMARKS was used") tried to narrow down page->pfmemalloc
setting, but it missed some places the pfmemalloc should be set.

So, in __slab_alloc, the unalignment pfmemalloc and ALLOC_NO_WATERMARKS
cause incorrect deactivate_slab() on our core2 server:

    64.73%           fio  [kernel.kallsyms]     [k] _raw_spin_lock
                     |
                     --- _raw_spin_lock
                        |
                        |---0.34%-- deactivate_slab
                        |          __slab_alloc
                        |          kmem_cache_alloc
                        |          |

That causes our fio sync write performance to have a 40% regression.

Move the checking in get_page_from_freelist() which resolves this issue.

Signed-off-by: Alex Shi <alex.shi@intel.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: David Miller <davem@davemloft.net
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Sage Weil <sage@inktank.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:03 -07:00
Ilya Shchepetkov
5ed12f1282 drivers/rtc/rtc-pcf2123.c: initialize dynamic sysfs attributes
Dynamically allocated sysfs attributes must be initialized using
sysfs_attr_init(), otherwise lockdep complains: BUG: key <address> not in
.data!

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Ilya Shchepetkov <shchepetkov@ispras.ru>
Cc: Chris Verges <chrisv@cyberswitching.com>
Cc: Christian Pellegrin <chripell@fsfe.org>
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>
2012-08-21 16:45:03 -07:00
Minchan Kim
c81758fbe0 mm/compaction.c: fix deferring compaction mistake
Commit aff622495c ("vmscan: only defer compaction for failed order and
higher") fixed bad deferring policy but made mistake about checking
compact_order_failed in __compact_pgdat().  So it can't update
compact_order_failed with the new order.  This ends up preventing
correct operation of policy deferral.  This patch fixes it.

Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:03 -07:00
Robin Holt
7838f994b4 drivers/misc/sgi-xp/xpc_uv.c: SGI XPC fails to load when cpu 0 is out of IRQ resources
On many of our larger systems, CPU 0 has had all of its IRQ resources
consumed before XPC loads.  Worst cases on machines with multiple 10
GigE cards and multiple IB cards have depleted the entire first socket
of IRQs.

This patch makes selecting the node upon which IRQs are allocated (as
well as all the other GRU Message Queue structures) specifiable as a
module load param and has a default behavior of searching all nodes/cpus
for an available resources.

[akpm@linux-foundation.org: fix build: include cpu.h and module.h]
Signed-off-by: Robin Holt <holt@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:03 -07:00
WANG Cong
c3a5ce0416 string: do not export memweight() to userspace
Fix the following warning:

  usr/include/linux/string.h:8: userspace cannot reference function or variable defined in the kernel

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:03 -07:00
Zhouping Liu
d46f3d86fd hugetlb: update hugetlbpage.txt
Commit f0f57b2b14 ("mm: move hugepage test examples to
tools/testing/selftests/vm") moved map_hugetlb.c, hugepage-shm.c and
hugepage-mmap.c tests into tools/testing/selftests/vm/ directory, but it
didn't update hugetlbpage.txt

Signed-off-by: Zhouping Liu <sanweidaying@gmail.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:03 -07:00
Joe Perches
ac8e97f8a7 checkpatch: add control statement test to SINGLE_STATEMENT_DO_WHILE_MACRO
Commit b13edf7ff2 ("checkpatch: add checks for do {} while (0) macro
misuses") added a test that is overly simplistic for single statement
macros.

Macros that start with control tests should be enclosed in a do {} while
(0) loop.

Add the necessary control tests to the check.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Andy Whitcroft <apw@canonical.com>
Tested-by: Franz Schrober <franzschrober@yahoo.de>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:02 -07:00
Michal Hocko
eb48c07146 mm: hugetlbfs: correctly populate shared pmd
Each page mapped in a process's address space must be correctly
accounted for in _mapcount.  Normally the rules for this are
straightforward but hugetlbfs page table sharing is different.  The page
table pages at the PMD level are reference counted while the mapcount
remains the same.

If this accounting is wrong, it causes bugs like this one reported by
Larry Woodman:

  kernel BUG at mm/filemap.c:135!
  invalid opcode: 0000 [#1] SMP
  CPU 22
  Modules linked in: bridge stp llc sunrpc binfmt_misc dcdbas microcode pcspkr acpi_pad acpi]
  Pid: 18001, comm: mpitest Tainted: G        W    3.3.0+ #4 Dell Inc. PowerEdge R620/07NDJ2
  RIP: 0010:[<ffffffff8112cfed>]  [<ffffffff8112cfed>] __delete_from_page_cache+0x15d/0x170
  Process mpitest (pid: 18001, threadinfo ffff880428972000, task ffff880428b5cc20)
  Call Trace:
    delete_from_page_cache+0x40/0x80
    truncate_hugepages+0x115/0x1f0
    hugetlbfs_evict_inode+0x18/0x30
    evict+0x9f/0x1b0
    iput_final+0xe3/0x1e0
    iput+0x3e/0x50
    d_kill+0xf8/0x110
    dput+0xe2/0x1b0
    __fput+0x162/0x240

During fork(), copy_hugetlb_page_range() detects if huge_pte_alloc()
shared page tables with the check dst_pte == src_pte.  The logic is if
the PMD page is the same, they must be shared.  This assumes that the
sharing is between the parent and child.  However, if the sharing is
with a different process entirely then this check fails as in this
diagram:

  parent
    |
    ------------>pmd
                 src_pte----------> data page
                                        ^
  other--------->pmd--------------------|
                  ^
  child-----------|
                 dst_pte

For this situation to occur, it must be possible for Parent and Other to
have faulted and failed to share page tables with each other.  This is
possible due to the following style of race.

  PROC A                                          PROC B
  copy_hugetlb_page_range                         copy_hugetlb_page_range
    src_pte == huge_pte_offset                      src_pte == huge_pte_offset
    !src_pte so no sharing                          !src_pte so no sharing

  (time passes)

  hugetlb_fault                                   hugetlb_fault
    huge_pte_alloc                                  huge_pte_alloc
      huge_pmd_share                                 huge_pmd_share
        LOCK(i_mmap_mutex)
        find nothing, no sharing
        UNLOCK(i_mmap_mutex)
                                                      LOCK(i_mmap_mutex)
                                                      find nothing, no sharing
                                                      UNLOCK(i_mmap_mutex)
      pmd_alloc                                       pmd_alloc
      LOCK(instantiation_mutex)
      fault
      UNLOCK(instantiation_mutex)
                                                  LOCK(instantiation_mutex)
                                                  fault
                                                  UNLOCK(instantiation_mutex)

These two processes are not poing to the same data page but are not
sharing page tables because the opportunity was missed.  When either
process later forks, the src_pte == dst pte is potentially insufficient.
As the check falls through, the wrong PTE information is copied in
(harmless but wrong) and the mapcount is bumped for a page mapped by a
shared page table leading to the BUG_ON.

This patch addresses the issue by moving pmd_alloc into huge_pmd_share
which guarantees that the shared pud is populated in the same critical
section as pmd.  This also means that huge_pte_offset test in
huge_pmd_share is serialized correctly now which in turn means that the
success of the sharing will be higher as the racing tasks see the pud
and pmd populated together.

Race identified and changelog written mostly by Mel Gorman.

{akpm@linux-foundation.org: attempt to make the huge_pmd_share() comment comprehensible, clean up coding style]
Reported-by: Larry Woodman <lwoodman@redhat.com>
Tested-by: Larry Woodman <lwoodman@redhat.com>
Reviewed-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Ken Chen <kenchen@google.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:02 -07:00
Stephen M. Cameron
b0cf0b118c cciss: fix incorrect scsi status reporting
Delete code which sets SCSI status incorrectly as it's already been set
correctly above this incorrect code.  The bug was introduced in 2009 by
commit b0e15f6db1 ("cciss: fix typo that causes scsi status to be
lost.")

Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Reported-by: Roel van Meer <roel.vanmeer@bokxing.nl>
Tested-by: Roel van Meer <roel.vanmeer@bokxing.nl>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:02 -07:00
Namjae Jeon
d65226e2bf Documentation: update mount option in filesystem/vfat.txt
Update two mount options(discard, nfs) in vfat.txt.

Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:02 -07:00
Hugh Dickins
f9aed62a2b mm: change nr_ptes BUG_ON to WARN_ON
Occasionally an isolated BUG_ON(mm->nr_ptes) gets reported, indicating
that not all the page tables allocated could be found and freed when
exit_mmap() tore down the user address space.

There's usually nothing we can say about it, beyond that it's probably a
sign of some bad memory or memory corruption; though it might still
indicate a bug in vma or page table management (and did recently reveal a
race in THP, fixed a few months ago).

But one overdue change we can make is from BUG_ON to WARN_ON.

It's fairly likely that the system will crash shortly afterwards in some
other way (for example, the BUG_ON(page_mapped(page)) in
__delete_from_page_cache(), once an inode mapped into the lost page tables
gets evicted); but might tell us more before that.

Change the BUG_ON(page_mapped) to WARN_ON too?  Later perhaps: I'm less
eager, since that one has several times led to fixes.

Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 16:45:02 -07:00