kernel/printk.c: document possible deadlock against scheduler

The printk's comment states that it can be called from every context,
which might lead to false illusion that it could be called from everywhere
without any restrictions.

This is however not true - a call to printk() could deadlock if called from
scheduler code (namely from schedule(), wake_up(), etc) on runqueue lock
when it tries to wake up klogd. Document this.
Signed-off-by: NJiri Kosina <jkosina@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Static initialization of spinlocks is preferable to dynamic initialization
when it is practical.  This patch updates documentation for consistency
with comments in spinlock_types.h.
Signed-off-by: NEd L. Cashin <ecashin@coraid.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove the broken 'no termios change' optimisation for this driver.
Signed-off-by: NAlan Cox <alan@redhat.com>
Cc: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Again this check is wrong now, and un-needed
Signed-off-by: NAlan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We've been using the 'new locking' for a long time now so it seems
pointless keeping the old one around.  Remove it and undo the macros it
uses back into real code for readability.  Remove the bogus 'no termios
change' checks.
Signed-off-by: NAlan Cox <alan@redhat.com>
Cc: Morten Helgesen <morten@sourcepoet.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Lots of serial drivers check and optimise for setting the termios values to
the ones they were before.  This is pointless and the check is wrong
anyway.  Remove the checks on the serial drivers.  If we ever do need such
a check put it back in the tty layer instead _once_!
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Now we always use stop_machine for module insertion or deletion, we no
longer need the modlist_lock: merely disabling preemption is sufficient to
block against list manipulation.  This avoids deadlock on OOPSen where we
can potentially grab the lock twice.

Bug: 8695
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tobias Oed <tobiasoed@hotmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix error handling in ext4_create_journal according to kernel conventions.
Signed-off-by: NBorislav Petkov <bbpetkov@yahoo.de>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix error handling in ext3_create_journal according to kernel conventions.
Signed-off-by: NBorislav Petkov <bbpetkov@yahoo.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Change cancel_work_sync() and cancel_delayed_work_sync() to return a boolean
indicating whether the work was actually cancelled.  A zero return value means
that the work was not pending/queued.

Without that kind of change it is not possible to avoid flush_workqueue()
sometimes, see the next patch as an example.

Also, this patch unifies both functions and kills the (unlikely) busy-wait
loop.
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Acked-by: NJarek Poplawski <jarkao2@o2.pl>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Imho, the current naming of cancel_xxx workqueue functions is very confusing.

	cancel_delayed_work()
	cancel_rearming_delayed_work()
	cancel_rearming_delayed_workqueue()	// obsolete

	cancel_work_sync()

This looks as if the first 2 functions differ in "type" of their argument
which is not true any longer, nowadays the difference is the behaviour.

The semantics of cancel_rearming_delayed_work(dwork) was changed
significantly, it doesn't require that dwork rearms itself, and cancels dwork
synchronously.

Rename it to cancel_delayed_work_sync().  This matches cancel_delayed_work()
and cancel_work_sync().  Re-create cancel_rearming_delayed_work() as a simple
inline obsolete wrapper, like cancel_rearming_delayed_workqueue().
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Acked-by: NJarek Poplawski <jarkao2@o2.pl>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Update Documentation/filesystems/vfs.txt
Signed-off-by: NBorislav Petkov <bbpetkov@yahoo.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The UMSDOS filesystem was removed back in 2.6.11, but some tiny bits stuck
around.  This patch removes the few remaining leftovers.  The only things
left behind after this are the entries in the CREDITS file and the ioctl
number in Documentation/ioctl-number.txt as documentation.

This third (hopefully final) version of the patch doesn't edit the
arch/um/config.release file, since Jeff Dike pointed out to me that it
should die completely, and asked me to remove it from my patch as he'll
send in a seperate patch removing the file completely.
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add descriptions for a number of missing files and directories to the
Documentation/00-INDEX file.
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Acked-by: NRob Landley <rob@landley.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Using dev_to_node(&dev->dev) to get node, and kmalloc_node to dma buffer on
corresponding node dma pool
Signed-off-by: NYinghai Lu <yinghai.lu@sun.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We have to change udf_crc16() name to udf_crc() to be able to play with CRC
test.
Signed-off-by: NCyrill Gorcunov <gorcunov@gmail.com>
Cc: Jan Kara <jack@ucw.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The current generic bug implementation has a call to dump_stack() in case a
WARN_ON(whatever) gets hit.  Since report_bug(), which calls dump_stack(),
gets called from an exception handler we can do better: just pass the
pt_regs structure to report_bug() and pass it to show_regs() in case of a
warning.  This will give more debug informations like register contents,
etc...  In addition this avoids some pointless lines that dump_stack()
emits, since it includes a stack backtrace of the exception handler which
is of no interest in case of a warning.  E.g.  on s390 the following lines
are currently always present in a stack backtrace if dump_stack() gets
called from report_bug():

 [<000000000001517a>] show_trace+0x92/0xe8)
 [<0000000000015270>] show_stack+0xa0/0xd0
 [<00000000000152ce>] dump_stack+0x2e/0x3c
 [<0000000000195450>] report_bug+0x98/0xf8
 [<0000000000016cc8>] illegal_op+0x1fc/0x21c
 [<00000000000227d6>] sysc_return+0x0/0x10
Acked-by: NJeremy Fitzhardinge <jeremy@goop.org>
Acked-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Kyle McMartin <kyle@parisc-linux.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add -Werror-implicit-function-declaration
This makes builds fail sooner if something is implicitly defined instead
of having to wait half an hour for it to fail at the linking stage.
Signed-off-by: NDave Jones <davej@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is a rather bizarre thing to have inlined in io.h.  Stick it in lib/
instead.

While we're there, despaghetti it a bit, and fix its off-by-one behaviour when
passed a zero length.
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I recently received a patch including a file that had a vim modeline,
and I realized that nothing specifically proscribed that practice.
Signed-off-by: NJosh Triplett <josh@freedesktop.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NJosh Triplett <josh@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Replace (n & (n-1)) with is_power_of_2
Signed-off-by: Nvignesh babu <vignesh.babu@wipro.com>
Acked-by: NEvgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The IO port range requested by parport_pc.c:sio_ite_8872_probe is too small.
The IO-ports of ttyS1 (0x2f8) will be missconfigured by the ITE-chip.  The ITE
starts looking for the chip a 0x2a0.  An IO-portrange of 32 will not overwrite
the ports of ttyS1.  Therefore register 0x60 should be written with
0xe5000000, enabling the ITE and setting IO-portsize to 32 bytes.
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Replace (n & (n-1)) with is_power_of_2()
Signed-off-by: Nvignesh babu <vignesh.babu@wipro.com>
Acked-by: NStelian Pop <stelian@popies.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This follows a suggestion from Chuck Ebbert on how to make seccomp
absolutely zerocost in schedule too.  The only remaining footprint of
seccomp is in terms of the bzImage size that becomes a few bytes (perhaps
even a few kbytes) larger, measure it if you care in the embedded.
Signed-off-by: NAndrea Arcangeli <andrea@cpushare.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reduces the memory footprint and it enforces that only the current
task can enable seccomp on itself (this is a requirement for a
strightforward [modulo preempt ;) ] TIF_NOTSC implementation).
Signed-off-by: NAndrea Arcangeli <andrea@cpushare.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

sock_xmit() re-implements sigprocmask() and dequeue_signal_lock().
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Acked-by: NPaul Clements <paul.clements@steeleye.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kcdrwd() is a kernel thread, all signals are ignored.
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Cc: Peter Osterlund <petero2@telia.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

adb_probe_task() is forked by "events" thread, all signals are ignored, no
need to play with signal blocking/flushing.
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix this:

fs/block_dev.c: In function 'bd_claim_by_disk':
fs/block_dev.c:970: warning: 'found' may be used uninitialized in this function

and given that free_bd_holder() now needs free(NULL)-is-legal behaviour, we
can simplify bd_release_from_kobject().

Cc: Bjorn Steinbrink <B.Steinbrink@gmx.de>
Cc: Johannes Weiner <hannes-kernel@saeurebad.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Replace some funky codepaths in fs/block_dev.c with cleaner versions of the
affected places.

[akpm@linux-foundation.org: fix return value]
Signed-off-by: NJohannes Weiner <hannes-kernel@saeurebad.de>
Cc: Bjorn Steinbrink <B.Steinbrink@gmx.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Every file should include the headers containing the prototypes for
its global functions.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove pointless `else'.
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add custom dentry hash and comparison operations for HFS+ filesystems that are
case-insensitive and/or do automatic unicode decomposition.  The new
operations reuse the existing HFS+ ASCII to unicode conversion, unicode
decomposition and case folding functionality.
Signed-off-by: NDuane Griffin <duaneg@dghda.com>
Signed-off-by: NRoman Zippel <zippel@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The HFS+ filesystem is case-insensitive and does automatic unicode
decomposition by default, but does not provide custom dentry operations.  This
can lead to multiple dentries being cached for lookups on a filename with
varying case and/or character (de)composition.

These patches add custom dentry hash and comparison operations for
case-sensitive and/or automatically decomposing HFS+ filesystems.  Unicode
decomposition and case-folding are performed as required to ensure equivalent
filenames are hashed to the same values and compare as equal.

This patch:

Refactor existing HFS+ ASCII to unicode string conversion routine to split out
character conversion functionality.  This will be reused by the custom dentry
hash and comparison routines.  This approach avoids unnecessary memory
allocation compared to using the string conversion routine directly in the new
functions.

[akpm@linux-foundation.org: avoid use-of-uninitialised]
Signed-off-by: NDuane Griffin <duaneg@dghda.com>
Signed-off-by: NRoman Zippel <zippel@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In ext4_new_blocks(), one of two ext4_block_bitmap() calls should be
ext4_inode_bitmap() call.  It is not harmful in normal processing, but it
should be fixed.
Signed-off-by: NToshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
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>

Hopefully this will help people to understand the new regime.

Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Poeple keep on adding new numbered sysctls, when they're supposed not to.

Add a documentation file which explain why new sysctls should use
CTL_UNNUMBERED.  The next patch will sprinkle pointers to this throughout
sysctl.c.

Eric provided the text (thanks)

Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The recent PRIVATE and REQUEUE_PI changes to the futex code made it hard to
read.  Tidy it up.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>