async: introduce 'async_domain' type

This is in preparation for teaching async_synchronize_full() to sync all
pending async work, and not just on the async_running domain.  This
conversion is functionally equivalent, just embedding the existing list
in a new async_domain type.

The .registered attribute is used in a later patch to distinguish
between domains that want to be flushed by async_synchronize_full()
versus those that only expect async_synchronize_{full|cookie}_domain to
be used for flushing.

[jejb: add async.h to scsi_priv.h for struct async_domain]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Tested-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
crypto: arm-aes - fix encryption of unaligned data

Fix the same alignment bug as in arm64 - we need to pass residue
unprocessed bytes as the last argument to blkcipher_walk_done.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org	# 3.13+
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
ARM: make kernel oops easier to read

We don't need the offset for the first function name in each backtrace
entry; this needlessly consumes screen space.  This is virtually always
the first or second instruction in the called function.

Also, recognise stmfd instructions which include r10 as a valid stack
saving instruction, and when dumping the registers, dump six registers
per line rather than five, and fix the wrapping.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
initramfs: remove "compression mode" choice

Commit ("initramfs: read CONFIG_RD_ variables for initramfs compression")
removed the users of the various INITRAMFS_COMPRESSION_*
Kconfig symbols.  So since v3.13 the entire "Built-in initramfs
compression mode" choice is a set of knobs connected to nothing.  The
entire choice can safely be removed.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Cc: P J P <ppandit@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
kconfig: update compression algorithm info

There have been new compression algorithms added without updating nearby
relevant descriptive text that refers to (a) the number of compression
algorithms and (b) the most recent one.  Fix these inconsistencies.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Reported-by: <qasdfgtyuiop@gmail.com>
Cc: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
scripts/gen_initramfs_list.sh: fix flags for initramfs LZ4 compression

LZ4 as implemented in the kernel differs from the default method now
used by the reference implementation of LZ4.  Until the in-kernel method
is updated to support the new default, passing the legacy flag (-l) to
the compressor is necessary.  Without this flag the kernel-generated,
LZ4-compressed initramfs is junk.

Kyungsik said:

: It seems that lz4 supports legacy format with the same option as lz4c
: does.  Just looking at the first few bytes of lz4 compressed image, we can
: see whether it is new format or not.
:
: It shows new format magic number without this patch.  New format magic
: number is 0x184d2204.
:
: $ hexdump -C ./initramfs_data.cpio.lz4 |more
: 00000000  04 22 4d 18 64 70 b9 69 (Little Endian)
: ...
:
: Currently kernel supports legacy format only.

Signed-off-by: Daniel M. Weeks <dan@danweeks.net>
Cc: Michal Marek <mmarek@suse.cz>
Acked-by: Kyungsik Lee <kyungsik.lee@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
gen_init_cpio: remove redundant empty line

Just a completely trivial patch to remove a completely redundant blank
line from usr/gen_init_cpio.c

Signed-off-by: Jesper Juhl <jj@codesealer.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
getenv() may return NULL if given environment variable does not exist which leads to NULL dereference when calling strncat.

Besides that, the environment variable name was copied to a temporary
env_var buffer, but this copying can be avoided by simply using the input
string.

Lastly, the whole loop can be greatly simplified by using the snprintf
function instead of the playing with strncat.

 By the way, the current implementation allows a recursive variable
 expansion, as in:

   $ echo 'out ${A} out ' | A='a ${B} a' B=b /tmp/a
   out a b a out

 I'm assuming this is just a side effect and not a conscious decision
 (especially as this may lead to infinite loop), but I didn't want to
 change this behaviour without consulting.

 If the current behaviour is deamed incorrect, I'll be happy to send
 a patch without recursive processing.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Jesper Juhl <jj@codesealer.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
sync: don't block the flusher thread waiting on IO

When sync does it's WB_SYNC_ALL writeback, it issues data Io and
then immediately waits for IO completion. This is done in the
context of the flusher thread, and hence completely ties up the
flusher thread for the backing device until all the dirty inodes
have been synced. On filesystems that are dirtying inodes constantly
and quickly, this means the flusher thread can be tied up for
minutes per sync call and hence badly affect system level write IO
performance as the page cache cannot be cleaned quickly.

We already have a wait loop for IO completion for sync(2), so cut
this out of the flusher thread and delegate it to wait_sb_inodes().
Hence we can do rapid IO submission, and then wait for it all to
complete.

Effect of sync on fsmark before the patch:

FSUse%        Count         Size    Files/sec     App Overhead
.....
     0       640000         4096      35154.6          1026984
     0       720000         4096      36740.3          1023844
     0       800000         4096      36184.6           916599
     0       880000         4096       1282.7          1054367
     0       960000         4096       3951.3           918773
     0      1040000         4096      40646.2           996448
     0      1120000         4096      43610.1           895647
     0      1200000         4096      40333.1           921048

And a single sync pass took:

  real    0m52.407s
  user    0m0.000s
  sys     0m0.090s

After the patch, there is no impact on fsmark results, and each
individual sync(2) operation run concurrently with the same fsmark
workload takes roughly 7s:

  real    0m6.930s
  user    0m0.000s
  sys     0m0.039s

IOWs, sync is 7-8x faster on a busy filesystem and does not have an
adverse impact on ongoing async data write operations.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
net/l2tp: don't fall back on UDP [get|set]sockopt

The l2tp [get|set]sockopt() code has fallen back to the UDP functions
for socket option levels != SOL_PPPOL2TP since day one, but that has
never actually worked, since the l2tp socket isn't an inet socket.

As David Miller points out:

  "If we wanted this to work, it'd have to look up the tunnel and then
   use tunnel->sk, but I wonder how useful that would be"

Since this can never have worked so nobody could possibly have depended
on that functionality, just remove the broken code and return -EINVAL.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: James Chapman <jchapman@katalix.com>
Acked-by: David Miller <davem@davemloft.net>
Cc: Phil Turnbull <phil.turnbull@oracle.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
vsprintf: ignore %n again

This ignores %n in printf again, as was originally documented.
Implementing %n poses a greater security risk than utility, so it should
stay ignored.  To help anyone attempting to use %n, a warning will be
emitted if it is encountered.

Based on an earlier patch by Joe Perches.

Because %n was designed to write to pointers on the stack, it has been
frequently used as an attack vector when bugs are found that leak
user-controlled strings into functions that ultimately process format
strings.  While this class of bug can still be turned into an
information leak, removing %n eliminates the common method of elevating
such a bug into an arbitrary kernel memory writing primitive,
significantly reducing the danger of this class of bug.

For seq_file users that need to know the length of a written string for
padding, please see seq_setwidth() and seq_pad() instead.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David Brown <davidb@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
seq_file: introduce seq_setwidth() and seq_pad()

There are several users who want to know bytes written by seq_*() for
alignment purpose.  Currently they are using %n format for knowing it
because seq_*() returns 0 on success.

This patch introduces seq_setwidth() and seq_pad() for allowing them to
align without using %n format.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David Brown <davidb@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
seq_file: remove "%n" usage from seq_file users

All seq_printf() users are using "%n" for calculating padding size,
convert them to use seq_setwidth() / seq_pad() pair.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ravi Kumar <rsiddoji@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>

Conflicts:
	fs/proc/task_mmu.c
timekeeping: Add persistent_clock_exist flag

In current kernel, there are several places which need to check
whether there is a persistent clock for the platform. Current check
is done by calling the read_persistent_clock() and validating its
return value.

So one optimization is to do the check only once in timekeeping_init(),
and use a flag persistent_clock_exist to record it.

v2: Add a has_persistent_clock() helper function, as suggested by John.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
timekeeping: Correct run-time detection of persistent_clock.

Since commit 31ade30692dc9680bfc95700d794818fa3f754ac, timekeeping_init()
checks for presence of persistent clock by attempting to read a non-zero
time value. This is an issue on platforms where persistent_clock (instead
is implemented as a free-running counter (instead of an RTC) starting
from zero on each boot and running during suspend. Examples are some ARM
platforms (e.g. PandaBoard).

An attempt to read such a clock during timekeeping_init() may return zero
value and falsely declare persistent clock as missing. Additionally, in
the above case suspend times may be accounted twice (once from
timekeeping_resume() and once from rtc_resume()), resulting in a gradual
drift of system time.

This patch does a run-time correction of the issue by doing the same check
during timekeeping_suspend().

A better long-term solution would have to return error when trying to read
non-existing clock and zero when trying to read an uninitialized clock, but
that would require changing all persistent_clock implementations.

This patch addresses the immediate breakage, for now.

Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Feng Tang <feng.tang@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Zoran Markovic <zoran.markovic@linaro.org>
[jstultz: Tweaked commit message and subject]
Signed-off-by: John Stultz <john.stultz@linaro.org>
[Backport by Dorimanx]
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
time: create __getnstimeofday for WARNless calls

Expose getnstimeofday logic that returns
an error instead of a WARN. This can be detected and the timestamp can
be zeroed out.

Reported-by: Doug Anderson <dianders@chromium.org>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
timekeeping: Add suspend and resume of clock event devices

Some clock event devices, for example such that belong to PM domains,
need to be handled in a spcial way during the timekeeping suspend
and resume (which takes place in the system core, or "syscore",
stages of system power transitions) in analogy with clock sources.

Introduce .suspend() and .resume() callbacks for clock event devices
that will be executed by timekeeping_suspend/_resume(), respectively,
next the the clock sources' .suspend() and .resume() callbacks.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>

Conflicts:
	include/linux/clockchips.h
time: Move timekeeper structure to timekeeper_internal.h for vsyscall changes

We're going to need to access the timekeeper in update_vsyscall,
so make the structure available for those who need it.

Cc: Tony Luck <tony.luck@intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
sched/rt: print RT tasks when RT throttling is activated

Existing debug prints do not provide any clues about which tasks
may have triggered RT throttling. Print the names and PIDs of
all tasks on the throttled rt_rq to help narrow down the source
of the problem.

Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
sched/rt: Add Kconfig option to enable panicking for RT throttling

This may be useful for detecting and debugging RT throttling issues.

Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>