In a situation where Smack access rules allow processes
with multiple labels to write to a directory it is easy
to get into a situation where the directory gets cluttered
with files that the owner can't deal with because while
they could be written to the directory a process at the
label of the directory can't write them. This is generally
the desired behavior, but when it isn't it is a real
issue.

This patch introduces a new attribute SMACK64TRANSMUTE that
instructs Smack to create the file with the label of the directory
under certain circumstances.

A new access mode, "t" for transmute, is made available to
Smack access rules, which are expanded from "rwxa" to "rwxat".
If a file is created in a directory marked as transmutable
and if access was granted to perform the operation by a rule
that included the transmute mode, then the file gets the
Smack label of the directory instead of the Smack label of the
creating process.

Note that this is equivalent to creating an empty file at the
label of the directory and then having the other process write
to it. The transmute scheme requires that both the access rule
allows transmutation and that the directory be explicitly marked.
Signed-off-by: NJarkko Sakkinen <ext-jarkko.2.sakkinen@nokia.com>
Signed-off-by: NCasey Schaufler <casey@schaufler-ca.com>

SMACK64EXEC. It defines label that is used while task is
running.

Exception: in smack_task_wait() child task is checked
for write access to parent task using label inherited
from the task that forked it.

Fixed issues from previous submit:
- SMACK64EXEC was not read when SMACK64 was not set.
- inode security blob was not updated after setting
  SMACK64EXEC
- inode security blob was not updated when removing
  SMACK64EXEC

Comment for return value of security_key_permission() has been wrong
since it was added in 2.6.15.
Signed-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: NJames Morris <jmorris@namei.org>

Define a new kernel key-type called 'trusted'.  Trusted keys are random
number symmetric keys, generated and RSA-sealed by the TPM.  The TPM
only unseals the keys, if the boot PCRs and other criteria match.
Userspace can only ever see encrypted blobs.

Based on suggestions by Jason Gunthorpe, several new options have been
added to support additional usages.

The new options are:
migratable=  designates that the key may/may not ever be updated
             (resealed under a new key, new pcrinfo or new auth.)

pcrlock=n    extends the designated PCR 'n' with a random value,
             so that a key sealed to that PCR may not be unsealed
             again until after a reboot.

keyhandle=   specifies the sealing/unsealing key handle.

keyauth=     specifies the sealing/unsealing key auth.

blobauth=    specifies the sealed data auth.

Implementation of a kernel reserved locality for trusted keys will be
investigated for a possible future extension.

Changelog:
- Updated and added examples to Documentation/keys-trusted-encrypted.txt
- Moved generic TPM constants to include/linux/tpm_command.h
  (David Howell's suggestion.)
- trusted_defined.c: replaced kzalloc with kmalloc, added pcrlock failure
  error handling, added const qualifiers where appropriate.
- moved to late_initcall
- updated from hash to shash (suggestion by David Howells)
- reduced worst stack usage (tpm_seal) from 530 to 312 bytes
- moved documentation to Documentation directory (suggestion by David Howells)
- all the other code cleanups suggested by David Howells
- Add pcrlock CAP_SYS_ADMIN dependency (based on comment by Jason Gunthorpe)
- New options: migratable, pcrlock, keyhandle, keyauth, blobauth (based on
  discussions with Jason Gunthorpe)
- Free payload on failure to create key(reported/fixed by Roberto Sassu)
- Updated Kconfig and other descriptions (based on Serge Hallyn's suggestion)
- Replaced kzalloc() with kmalloc() (reported by Serge Hallyn)
Signed-off-by: NDavid Safford <safford@watson.ibm.com>
Signed-off-by: NMimi Zohar <zohar@us.ibm.com>
Signed-off-by: NJames Morris <jmorris@namei.org>

Add internal kernel tpm_send() command used to seal/unseal keys.

Changelog:
- replaced module_put in tpm_send() with new tpm_chip_put() wrapper
  (suggested by David Howells)
- Make tpm_send() cmd argument a 'void *' (suggested by David Howells)
Signed-off-by: NDavid Safford <safford@watson.ibm.com>
Signed-off-by: NMimi Zohar <zohar@us.ibm.com>
Acked-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NSerge E. Hallyn <serge.hallyn@canonical.com>
Signed-off-by: NJames Morris <jmorris@namei.org>

Similar to the kgdb_hex2mem() code, hex2bin converts a string
to binary using the hex_to_bin() library call.

Changelog:
- Replace parameter names with src/dst (based on David Howell's comment)
- Add 'const' where needed (based on David Howell's comment)
- Replace int with size_t (based on David Howell's comment)
Signed-off-by: NMimi Zohar <zohar@us.ibm.com>
Acked-by: NSerge E. Hallyn <serge@hallyn.com>
Acked-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NJames Morris <jmorris@namei.org>

Privileged syslog operations currently require CAP_SYS_ADMIN.  Split
this off into a new CAP_SYSLOG privilege which we can sanely take away
from a container through the capability bounding set.

With this patch, an lxc container can be prevented from messing with
the host's syslog (i.e. dmesg -c).

Changelog: mar 12 2010: add selinux capability2:cap_syslog perm
Changelog: nov 22 2010:
	. port to new kernel
	. add a WARN_ONCE if userspace isn't using CAP_SYSLOG
Signed-off-by: NSerge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: NAndrew G. Morgan <morgan@kernel.org>
Acked-By: NKees Cook <kees.cook@canonical.com>
Cc: James Morris <jmorris@namei.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: "Christopher J. PeBenito" <cpebenito@tresys.com>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: NJames Morris <jmorris@namei.org>

The stubs for CONFIG_INTR_REMAP disabled need to be functions
instead of values to eliminate build warnings.

 arch/x86/kernel/apic/apic.c: In function 'lapic_suspend':
 arch/x86/kernel/apic/apic.c:2060:3: warning: statement with no effect
 arch/x86/kernel/apic/apic.c: In function 'lapic_resume':
 arch/x86/kernel/apic/apic.c:2137:3: warning: statement with no effect
Reported-and-Tested-by: NFabio Comolli <fabio.comolli@gmail.com>
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
LKML-Reference: <20101122124834.74429004.randy.dunlap@oracle.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Fix this:

  kernel BUG at mm/memcontrol.c:2155!
  invalid opcode: 0000 [#1]
  last sysfs file:

  Pid: 18, comm: sh Not tainted 2.6.37-rc3 #3 /Bochs
  EIP: 0060:[<c10731b2>] EFLAGS: 00000246 CPU: 0
  EIP is at mem_cgroup_move_account+0xe2/0xf0
  EAX: 00000004 EBX: c6f931d4 ECX: c681c300 EDX: c681c000
  ESI: c681c300 EDI: ffffffea EBP: c681c000 ESP: c46f3e30
   DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068
  Process sh (pid: 18, ti=c46f2000 task=c6826e60 task.ti=c46f2000)
  Stack:
   00000155 c681c000 0805f000 c46ee180 c46f3e5c c7058820 c1074d37 00000000
   08060000 c46db9a0 c46ec080 c7058820 0805f000 08060000 c46f3e98 c1074c50
   c106c75e c46f3e98 c46ec080 08060000 0805ffff c46db9a0 c46f3e98 c46e0340
  Call Trace:
   [<c1074d37>] ? mem_cgroup_move_charge_pte_range+0xe7/0x130
   [<c1074c50>] ? mem_cgroup_move_charge_pte_range+0x0/0x130
   [<c106c75e>] ? walk_page_range+0xee/0x1d0
   [<c10725d6>] ? mem_cgroup_move_task+0x66/0x90
   [<c1074c50>] ? mem_cgroup_move_charge_pte_range+0x0/0x130
   [<c1072570>] ? mem_cgroup_move_task+0x0/0x90
   [<c1042616>] ? cgroup_attach_task+0x136/0x200
   [<c1042878>] ? cgroup_tasks_write+0x48/0xc0
   [<c1041e9e>] ? cgroup_file_write+0xde/0x220
   [<c101398d>] ? do_page_fault+0x17d/0x3f0
   [<c108a79d>] ? alloc_fd+0x2d/0xd0
   [<c1041dc0>] ? cgroup_file_write+0x0/0x220
   [<c1077ba2>] ? vfs_write+0x92/0xc0
   [<c1077c81>] ? sys_write+0x41/0x70
   [<c1140e3d>] ? syscall_call+0x7/0xb
  Code: 03 00 74 09 8b 44 24 04 e8 1c f1 ff ff 89 73 04 8d 86 b0 00 00 00 b9 01 00 00 00 89 da 31 ff e8 65 f5 ff ff e9 4d ff ff ff 0f 0b <0f> 0b 0f 0b 0f 0b 90 8d b4 26 00 00 00 00 83 ec 10 8b 0d f4 e3
  EIP: [<c10731b2>] mem_cgroup_move_account+0xe2/0xf0 SS:ESP 0068:c46f3e30
  ---[ end trace 7daa1582159b6532 ]---

lock_page_cgroup and unlock_page_cgroup are implemented using
bit_spinlock.  bit_spinlock doesn't touch the bit if we are on non-SMP
machine, so we can't use the bit to check whether the lock was taken.

Let's introduce is_page_cgroup_locked based on bit_spin_is_locked instead
of PageCgroupLocked to fix it.

[akpm@linux-foundation.org: s/is_page_cgroup_locked/page_is_cgroup_locked/]
Signed-off-by: NKirill A. Shutemov <kirill@shutemov.name>
Reviewed-by: NJohannes Weiner <hannes@cmpxchg.org>
Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujtisu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

dpkg uses fiemap but didn't particularly need to include stdint.h so far.
Since 367a51a3 ("fs: Add FITRIM ioctl"), build of linux/fs.h failed in
dpkg with:

  In file included from ../../src/filesdb.c:27:0:
  /usr/include/linux/fs.h:37:2: error: expected specifier-qualifier-list before 'uint64_t'

Use exportable type __u64 to avoid the dependency on stdint.h.

b31d42a5 ("Fix compile brekage with !CONFIG_BLOCK") fixed only the
kernel build by including linux/types.h, but this also fixed "make
headers_check", so don't revert it.
Signed-off-by: NLoïc Minier <loic.minier@linaro.org>
Tested-by: NArnd Bergmann <arnd.bergmann@linaro.org>
Cc: Lukas Czerner <lczerner@redhat.com>
Cc: Dmitry Monakhov <dmonakhov@openvz.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 9bea7f23 renamed use_module to
ref_module (and changed its return value), but forgot to update this
prototype in module.h.
Signed-off-by: NAnders Kaseorg <andersk@ksplice.com>
Acked-by: NWANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Store the dirent->d_type in the struct nfs_cache_array_entry so that we
can use it in getdents() calls.

This fixes a regression with the new readdir code.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The 88E1149R is 10/100/1000 quad-gigabit Ethernet PHY.  The
.config_aneg function can be shared with 88E1118, but it needs its own
.config_init.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
Cc: Cyril Chemparathy <cyril@ti.com>
Cc: Arnaud Patard <arnaud.patard@rtp-net.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There was concern that FITRIM ioctl is not common enough to be included
in core vfs ioctl, as Christoph Hellwig pointed out there's no real point
in dispatching this out to a separate vector instead of just through
->ioctl.

So this commit removes ioctl_fstrim() from vfs ioctl and trim_fs
from super_operation structure.
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Some board/card/host configurations are not capable of powering off the
card after boot.

To support such configurations, and to allow smoother transition to
runtime PM behavior, MMC_CAP_POWER_OFF_CARD is added, so hosts need to
explicitly indicate whether it's OK to power off their cards after boot.

SDIO core will enable runtime PM for a card only if that cap is set.
As a result, the card will be powered down after boot, and will only
be powered up again when a driver is loaded (and then it's up to the
driver to decide whether power will be kept or not).

This will prevent sdio_bus_probe() failures with setups that do not
support powering off the card.
Reported-and-tested-by: NDaniel Drake <dsd@laptop.org>
Reported-and-tested-by: NArnd Hannemann <arnd@arndnet.de>
Signed-off-by: NOhad Ben-Cohen <ohad@wizery.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

This really isn't the right thing to do, and strictly speaking we should
have the BKL depth count in the thread info right next to the preempt
count.  The two really do go together.

However, since that would involve a patch to all architectures, and the
BKL is finally going away, it's simply not worth the effort to do the
RightThing(tm).  Just re-instate the <linux/sched.h> include that we
used to get accidentally from the smp_lock.h one.

This is all fallout from the same old "BKL: remove extraneous #include
<smp_lock.h>" commit.
Reported-by: NIngo Molnar <mingo@elte.hu>
Tested-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 451a3c24 ("BKL: remove extraneous #include <smp_lock.h>")
removed the #include line that was the only thing that was surrounded by
the #ifdef/#endif.

So now that #ifdef is guarding nothing at all. Just remove it.
Reported-by: NByeong-ryeol Kim <brofkims@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Arnd Bergmann did an automated scripting run to find left-over instances
of <linux/smp_lock.h>, and had made it trigger it on the normal BKL use
of lock_kernel and unlock_lernel (and apparently release_kernel_lock and
reacquire_kernel_lock too, used by the scheduler).

That resulted in commit 451a3c24 ("BKL: remove extraneous #include
<smp_lock.h>").

However, hardirq.h was the only remaining user of the old
'kernel_locked()' interface, and Arnd's script hadn't checked for that.
So depending on your configuration and what header files had been
included, you would get errors like "implicit declaration of function
'kernel_locked'" during the build.

The right fix is not to just re-instate the smp_lock.h include - it is
to just remove 'kernel_locked()' entirely, since the only use was this
one special low-level detail.  Just make hardirq.h do it directly.

In fact this simplifies and clarifies the code, because some trivial
analysis makes it clear that hardirq.h only ever used _one_ of the two
definitions of kernel_locked(), so we can remove the other one entirely.
Reported-by: NZimny Lech <napohybelskurwysynom2010@gmail.com>
Reported-and-acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The big kernel lock has been removed from all these files at some point,
leaving only the #include.

Remove this too as a cleanup.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There is an integer overflow in fb_set_user_cmap() because cmap->len * 2
can wrap.  It's basically harmless.  Your terminal will be messed up
until you type reset.

This patch does three things to fix the bug.

First, it checks the return value of fb_copy_cmap() in fb_alloc_cmap().
That is enough to fix address the overflow.

Second it checks for the integer overflow in fb_set_user_cmap().

Lastly I wanted to cap "cmap->len" in fb_set_user_cmap() much lower
because it gets used to determine the size of allocation.  Unfortunately
no one knows what the limit should be.  Instead what this patch does
is makes the allocation happen with GFP_KERNEL instead of GFP_ATOMIC
and lets the kmalloc() decide what values of cmap->len are reasonable.
To do this, the patch introduces a function called fb_alloc_cmap_gfp()
which is like fb_alloc_cmap() except that it takes a GFP flag.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Move the mid-layer's ->queuecommand() invocation from being locked
with the host lock to being unlocked to facilitate speeding up the
critical path for drivers who don't need this lock taken anyway.

The patch below presents a simple SCSI host lock push-down as an
equivalent transformation.  No locking or other behavior should change
with this patch.  All existing bugs and locking orders are preserved.

Additionally, add one parameter to queuecommand,
	struct Scsi_Host *
and remove one parameter from queuecommand,
	void (*done)(struct scsi_cmnd *)

Scsi_Host* is a convenient pointer that most host drivers need anyway,
and 'done' is redundant to struct scsi_cmnd->scsi_done.

Minimal code disturbance was attempted with this change.  Most drivers
needed only two one-line modifications for their host lock push-down.
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
Acked-by: NJames Bottomley <James.Bottomley@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Nothing uses this macro anymore.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Nick Bowler reports:
There are no unusual messages on the client... but I just logged into
the server and I see lots of messages of the following form:

  nfsd: request from insecure port (192.168.8.199:35766)!
  nfsd: request from insecure port (192.168.8.199:35766)!
  nfsd: request from insecure port (192.168.8.199:35766)!
  nfsd: request from insecure port (192.168.8.199:35766)!
  nfsd: request from insecure port (192.168.8.199:35766)!

Bisected to commit 92476850 (SUNRPC:
Properly initialize sock_xprt.srcaddr in all cases)

Apparently, removing the 'transport->srcaddr.ss_family = family' from
xs_create_sock() triggers this due to nlmclnt_lookup_host() incorrectly
initialising the srcaddr family to AF_UNSPEC.
Reported-by: NNick Bowler <nbowler@elliptictech.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The addition of CONFIG_SECURITY_DMESG_RESTRICT resulted in a build
failure when CONFIG_PRINTK=n.  This is because the capabilities code
which used the new option was built even though the variable in question
didn't exist.

The patch here fixes this by moving the capabilities checks out of the
LSM and into the caller.  All (known) LSMs should have been calling the
capabilities hook already so it actually makes the code organization
better to eliminate the hook altogether.
Signed-off-by: NEric Paris <eparis@redhat.com>
Acked-by: NJames Morris <jmorris@namei.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It's about time to make it clear that i2c_adapter.id is deprecated.
Hopefully this will remind the last user to move over to a different
strategy.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Acked-by: NJarod Wilson <jarod@redhat.com>
Acked-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: NHans Verkuil <hverkuil@xs4all.nl>

Delete unused I2C adapter IDs. Special cases are:

* I2C_HW_B_RIVA was still set in driver rivafb, however no other
  driver is ever looking for this value, so we can safely remove it.
* I2C_HW_B_HDPVR is used in staging driver lirc_zilog, however no
  adapter ID is ever set to this value, so the code in question never
  runs. As the code additionally expects that I2C_HW_B_HDPVR may not
  be defined, we can delete it now and let the lirc_zilog driver
  maintainer rewrite this piece of code.

Big thanks for Hans Verkuil for doing all the hard work :)
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Acked-by: NJarod Wilson <jarod@redhat.com>
Acked-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: NHans Verkuil <hverkuil@xs4all.nl>

Move the logging bits from kernel.h into printk.h so that
there is a bit more logical separation of the generic from
the printk logging specific parts.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The commit below added a new helper dev_ingress_queue to cleanly obtain the
ingress queue pointer.  This necessitated including 'linux/netdevice.h':

  commit 24824a09
  Author: Eric Dumazet <eric.dumazet@gmail.com>
  Date:   Sat Oct 2 06:11:55 2010 +0000

    net: dynamic ingress_queue allocation

However this include triggers issues for applications in userspace
which use the rtnetlink interfaces.  Commonly this requires they include
'net/if.h' and 'linux/rtnetlink.h' leading to a compiler error as below:

  In file included from /usr/include/linux/netdevice.h:28:0,
                   from /usr/include/linux/rtnetlink.h:9,
                   from t.c:2:
  /usr/include/linux/if.h:135:8: error: redefinition of ‘struct ifmap’
  /usr/include/net/if.h:112:8: note: originally defined here
  /usr/include/linux/if.h:169:8: error: redefinition of ‘struct ifreq’
  /usr/include/net/if.h:127:8: note: originally defined here
  /usr/include/linux/if.h:218:8: error: redefinition of ‘struct ifconf’
  /usr/include/net/if.h:177:8: note: originally defined here

The new helper is only defined for the kernel and protected by __KERNEL__
therefore we can simply pull the include down into the same protected
section.
Signed-off-by: NAndy Whitcroft <apw@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Presently it's only legacy users that are using this clock op, guard it
with an ifdef to ensure that no new users start using it.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Now that clk_set_rate_ex() is gone, there is also no way to get at rate
setting algo id, which is now also completely unused. Kill it off before
new clock ops start using it.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

With the refactoring of the SH7722 clock framework some time ago this
abstraction has become unecessary. Kill it off before anyone else gets
the bright idea to start using it.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

The fsl-diu-fb driver no longer uses this define, and we have a common one
to cover this already (FBIO_WAITFORVSYNC).
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Depending on how a packet is vlan tagged (i.e. hardware accelerated or
not), the encapsulated protocol is stored in different locations.  This
provides a consistent method of accessing that protocol, which is needed
by drivers, security checks, etc.
Signed-off-by: NHao Zheng <hzheng@nicira.com>
Signed-off-by: NJesse Gross <jesse@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The intensity of the backlight can be varied from a range of
max_brightness to zero.  Though most, if not all the pwm based backlight
devices start flickering at lower brightness value.  And also for each
device there exists a brightness value below which the backlight appears
to be turned off though the value is not equal to zero.

If the range of brightness for a device is from zero to max_brightness.  A
graph is plotted for brightness Vs intensity for the pwm based backlight
device has to be a linear graph.

intensity
	  |   /
	  |  /
	  | /
	  |/
	  ---------
	 0	max_brightness

But pratically on measuring the above we note that the intensity of
backlight goes to zero(OFF) when the value in not zero almost nearing to
zero(some x%).  so the graph looks like

intensity
	  |    /
	  |   /
	  |  /
	  |  |
	  ------------
	 0   x	 max_brightness

In order to overcome this drawback knowing this x% i.e nothing but the low
threshold beyond which the backlight is off and will have no effect, the
brightness value is being offset by the low threshold value(retaining the
linearity of the graph).  Now the graph becomes

intensity
	  |     /
	  |    /
	  |   /
	  |  /
	  -------------
	   0	  max_brightness

With this for each and every digit increment in the brightness from zero
there is a change in the intensity of backlight.  Devices having this
behaviour can set the low threshold brightness(lth_brightness) and pass
the same as platform data else can have it as zero.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NArun Murthy <arun.murthy@stericsson.com>
Acked-by: NLinus Walleij <linus.walleij@stericsson.com>
Acked-by: NRichard Purdie <rpurdie@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

LP5523 chip is nine channel led driver with programmable engines.  Driver
provides support for that chip for direct access via led class or via
programmable engines.
Signed-off-by: NSamu Onkalo <samu.p.onkalo@nokia.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patchset provides support for LP5521 and LP5523 LED driver chips from
National Semicondutor.  Both drivers supports programmable engines and
naturally LED class features.

Documentation is provided as a part of the patchset.  I created "leds"
subdirectory under Documentation.  Perhaps the rest of the leds*
documentation should be moved there.

Datasheets are freely available at National Semiconductor www pages.

This patch:

LP5521 chip is three channel led driver with programmable engines.  Driver
provides support for that chip for direct access via led class or via
programmable engines.
Signed-off-by: NSamu Onkalo <samu.p.onkalo@nokia.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently, blinking LEDs can be awkward because it is not guaranteed that
all LEDs implement blinking.  The trigger that wants it to blink then
needs to implement its own timer solution.

Rather than require that, add led_blink_set() API that triggers can use.
This function will attempt to use hw blinking, but if that fails
implements a timer for it.  To stop blinking again, brightness_set() also
needs to be wrapped into API that will stop the software blink.

As a result of this, the timer trigger becomes a very trivial one, and
hopefully we can finally see triggers using blinking as well because it's
always easy to use.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Acked-by: NRichard Purdie <rpurdie@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Salman Qazi describes the following radix-tree bug:

In the following case, we get can get a deadlock:

0.  The radix tree contains two items, one has the index 0.
1.  The reader (in this case find_get_pages) takes the rcu_read_lock.
2.  The reader acquires slot(s) for item(s) including the index 0 item.
3.  The non-zero index item is deleted, and as a consequence the other item is
    moved to the root of the tree. The place where it used to be is queued for
    deletion after the readers finish.
3b. The zero item is deleted, removing it from the direct slot, it remains in
    the rcu-delayed indirect node.
4.  The reader looks at the index 0 slot, and finds that the page has 0 ref
    count
5.  The reader looks at it again, hoping that the item will either be freed or
    the ref count will increase. This never happens, as the slot it is looking
    at will never be updated. Also, this slot can never be reclaimed because
    the reader is holding rcu_read_lock and is in an infinite loop.

The fix is to re-use the same "indirect" pointer case that requires a slot
lookup retry into a general "retry the lookup" bit.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>
Reported-by: NSalman Qazi <sqazi@google.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The kernel syslog contains debugging information that is often useful
during exploitation of other vulnerabilities, such as kernel heap
addresses.  Rather than futilely attempt to sanitize hundreds (or
thousands) of printk statements and simultaneously cripple useful
debugging functionality, it is far simpler to create an option that
prevents unprivileged users from reading the syslog.

This patch, loosely based on grsecurity's GRKERNSEC_DMESG, creates the
dmesg_restrict sysctl.  When set to "0", the default, no restrictions are
enforced.  When set to "1", only users with CAP_SYS_ADMIN can read the
kernel syslog via dmesg(8) or other mechanisms.

[akpm@linux-foundation.org: explain the config option in kernel.txt]
Signed-off-by: NDan Rosenberg <drosenberg@vsecurity.com>
Acked-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NEugene Teo <eugeneteo@kernel.org>
Acked-by: NKees Cook <kees.cook@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 3e4d3af5 ("mm: stack based kmap_atomic()") introduced the
kmap_atomic_idx_push() function which warns on in_irq() with
CONFIG_DEBUG_HIGHMEM enabled.  This patch includes linux/hardirq.h for
the in_irq definition.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>