- switch to error message buffer in .bss
 - missing va_end() (htf it worked before?)
 - use vsnprintf()
 - rename variables to understandable "fmt", "args".
 - "const char *fmt", yes.
 - add __attribute__((format ...

Still, put that coffee down before reading more.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

It would very lame to get buffer overflow via one of the following.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This is on our "Envoy" boxes which we have, according to the documentation, an
"Exar ST16C554/554D Quad UART with 16-byte Fifo's".  The box also has two
other "on-board" serial ports and a modem chip.

The two on-board serial UARTs were being detected along with the first two
Exar UARTs.  The last two Exar UARTs were not showing up and neither was the
modem.

This patch was the only way I could the kernel to see beyond the standard four
serial ports and get all four of the Exar UARTs to show up.

[akpm@osdl.org: build fix]
Signed-off-by: NPaul B Schroeder <pschroeder@uplogix.com>
Cc: Lennart Sorensen <lsorense@csclub.uwaterloo.ca>
Acked-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

    =============================================
    [ INFO: possible recursive locking detected ]
    2.6.18-1.2699.fc6 #1
    ---------------------------------------------
    swapper/0 is trying to acquire lock:
     (&list->lock#3){+...}, at: [<c05ad307>] skb_dequeue+0x12/0x43

    but task is already holding lock:
     (&list->lock#3){+...}, at: [<df98cd79>] bcsp_dequeue+0x6a/0x11e [hci_uart]

Two different list locks nest, annotate so.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

One of the mistakes a module_param() user can make is to supply default
value of module parameter as the last argument.  module_param() accepts
permissions instead.  If default value is, say, 3 (-------wx), parameter
becomes world-writeable.

So far, the only remedy was to apply grep(1) and read drivers submitted
to -mm. BTDT.

With this patch applied, compiler will finally do some job.

*) bounds checking on permissions
*) world-writeable bit checking on permissions
*) compile breakage if checks trigger

First version of this check (only "& 2" part) directly caught 4 out of 7
places during my last grep.

    Subject: Neverending module_param() bugs
    [X] drivers/acpi/sbs.c:101:module_param(capacity_mode, int, CAPACITY_UNIT);
    [X] drivers/acpi/sbs.c:102:module_param(update_mode, int, UPDATE_MODE);
    [ ] drivers/acpi/sbs.c:103:module_param(update_info_mode, int, UPDATE_INFO_MODE);
    [ ] drivers/acpi/sbs.c:104:module_param(update_time, int, UPDATE_TIME);
    [ ] drivers/acpi/sbs.c:105:module_param(update_time2, int, UPDATE_TIME2);
    [X] drivers/char/watchdog/sbc8360.c:203:module_param(timeout, int, 27);
    [X] drivers/media/video/tuner-simple.c:13:module_param(offset, int, 0666);
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Thomas Graf wrote:
>
> nla_nest_start() may return NULL, either rely on prepare_reply() to be
> correct and BUG() on failure or do proper error handling for all
> functions.

nla_put() in taskstat.c can fail only if the 'size' argument of alloc_skb()
was not right. This is a kernel bug, we should not hide it. So add 'BUG()'
on error path and check for 'na == NULL'.

> genlmsg_cancel() is only required in error paths for dumping
> procedures.

So we can remove 'genlmsg_cancel()' calls and 'void *reply' (saves 227 bytes).
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jay Lan <jlan@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Currently taskstats_user_cmd()/taskstats_exit() do:

	1) allocate stats
	2) fill stats
	3) make a temporary copy on stack (236 bytes)
	4) copy that copy to skb
	5) free stats

With the help of nla_reserve() we can operate on skb->data directly,
thus avoiding all these steps except 2).

So, before this patch:

	// copy *stats to skb->data
	int mk_reply(skb, ..., struct taskstats *stats);

	fill_pid(stats);
	mk_reply(skb, ..., stats);

After:
	// return a pointer to skb->data
	struct taskstats *mk_reply(skb, ...);

	stat = mk_reply(skb, ...);
	fill_pid(stats);

Shrinks taskatsks.o by 162 bytes.

A stupid benchmark (send one million TASKSTATS_CMD_ATTR_PID) shows the

		real user sys
	before:
		4.02 0.06 3.96
		4.02 0.04 3.98
		4.02 0.04 3.97
	after:
		3.86 0.08 3.78
		3.88 0.10 3.77
		3.89 0.09 3.80

but this looks suspiciously good.
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Acked-by: NShailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jay Lan <jlan@sgi.com>
Cc: Thomas Graf <tgraf@suug.ch>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Introduce mk_reply() helper which does all nla_put()s on reply.

Saves 453 bytes and a preparation for the next patch.
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Acked-by: NShailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jay Lan <jlan@sgi.com>
Cc: Thomas Graf <tgraf@suug.ch>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Allocate ->signal->stats on demand in taskstats_exit(), this allows us to
remove taskstats_tgid_alloc() (the last non-trivial inline) from taskstat's
public interface.
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

do_exit:
	taskstats_exit_alloc()
	...
	taskstats_exit_send()
	taskstats_exit_free()

I think this is not good, let it be a single function exported to the core
kernel, taskstats_exit(), which does alloc + send + free itself.
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

If there are no listeners, every task does unneeded kmem_cache alloc/free on
exit. We don't need listeners->sem for 'if (!list_empty())' check. Yes, we may
have a false positive, but this doesn't differ from the case when the listener
is unregistered after we drop the semaphore. So we don't need to do allocation
beforehand.
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Cc: Balbir Singh <balbir@in.ibm.com>
Acked-by: NShailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Use put_pages_list() instead of opencoding it.
Signed-off-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch makes module init return proper value instead of -1 (-EPERM).

Cc: Tim Waugh <tim@cyberelk.net>
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

probe_kernel_address() purports to be generic, only it forgot to select
KERNEL_DS, so it presently won't work right on all architectures.
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add support for the parallel port (implemented as separate PCI function) on
the Oxford Semiconductor OX16PCI952.
Signed-off-by: NRyan Underwood <nemesis@icequake.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Make PRINTK_TIME depend on PRINTK.  Only display/offer it if PRINTK is
enabled.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The CLONE_CHILD_CLEARTID flag is used by NPTL to have its threads
communicate via memory/futex when they exit, so pthread_join can
synchronize using a simple futex wait.  The word of user memory where NPTL
stores a thread's own TID is what it passes; this gets reset to zero at
thread exit.

It is not desireable to touch this user memory when threads are dying due
to a fatal signal.  A core dump is more usefully representative of the
dying program state if the threads live at the time of the crash have their
NPTL data structures unperturbed.  The userland expectation of
CLONE_CHILD_CLEARTID has only ever been that it works for a thread making
an _exit system call.

This problem was identified by Ernie Petrides <petrides@redhat.com>.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Cc: Ernie Petrides <petrides@redhat.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Acked-by: NIngo Molnar <mingo@elte.hu>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Function v9fs_get_idpool returns int, not u32.  Actually it returns -1 on
errors, and these two callers check if the value is smaller than 0, which
was caught by gcc with extra warning flags.  Compile tested only but should
be OK, as the value computed in v9fs_get_idpool() is also int.
Signed-of-by: NMika Kukkonen <mikukkon@iki.fi>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@lanl.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix sparse NULL warning;
  drivers/misc/tifm_core.c:223:17: warning: Using plain integer as NULL pointer

Fix style while there.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

I've been using Steve Grubb's purely evil "fsfuzzer" tool, at
http://people.redhat.com/sgrubb/files/fsfuzzer-0.4.tar.gz

Basically it makes a filesystem, splats some random bits over it, then
tries to mount it and do some simple filesystem actions.

At best, the filesystem catches the corruption gracefully.  At worst,
things spin out of control.

As you might guess, we found a couple places in ext4 where things spin out
of control :)

First, we had a corrupted directory that was never checked for
consistency...  it was corrupt, and pointed to another bad "entry" of
length 0.  The for() loop looped forever, since the length of
ext4_next_entry(de) was 0, and we kept looking at the same pointer over and
over and over and over...  I modeled this check and subsequent action on
what is done for other directory types in ext4_readdir...

(adding this check adds some computational expense; I am testing a followup
patch to reduce the number of times we check and re-check these directory
entries, in all cases.  Thanks for the idea, Andreas).

Next we had a root directory inode which had a corrupted size, claimed to
be > 200M on a 4M filesystem.  There was only really 1 block in the
directory, but because the size was so large, readdir kept coming back for
more, spewing thousands of printk's along the way.

Per Andreas' suggestion, if we're in this read error condition and we're
trying to read an offset which is greater than i_blocks worth of bytes,
stop trying, and break out of the loop.

With these two changes fsfuzz test survives quite well on ext4.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

I've been using Steve Grubb's purely evil "fsfuzzer" tool, at
http://people.redhat.com/sgrubb/files/fsfuzzer-0.4.tar.gz

Basically it makes a filesystem, splats some random bits over it, then
tries to mount it and do some simple filesystem actions.

At best, the filesystem catches the corruption gracefully.  At worst,
things spin out of control.

As you might guess, we found a couple places in ext3 where things spin out
of control :)

First, we had a corrupted directory that was never checked for
consistency...  it was corrupt, and pointed to another bad "entry" of
length 0.  The for() loop looped forever, since the length of
ext3_next_entry(de) was 0, and we kept looking at the same pointer over and
over and over and over...  I modeled this check and subsequent action on
what is done for other directory types in ext3_readdir...

(adding this check adds some computational expense; I am testing a followup
patch to reduce the number of times we check and re-check these directory
entries, in all cases.  Thanks for the idea, Andreas).

Next we had a root directory inode which had a corrupted size, claimed to
be > 200M on a 4M filesystem.  There was only really 1 block in the
directory, but because the size was so large, readdir kept coming back for
more, spewing thousands of printk's along the way.

Per Andreas' suggestion, if we're in this read error condition and we're
trying to read an offset which is greater than i_blocks worth of bytes,
stop trying, and break out of the loop.

With these two changes fsfuzz test survives quite well on ext3.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Randomizes -pie compiled binaries from 64k (0x10000) up to ELF_ET_DYN_BASE.

0 -> 64k is excluded to allow NULL ptr accesses to fail.
Signed-off-by: NMarcus Meissner <meissner@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

 - numeric string size replaced with constant in print_lock_name and
   print_lockdep_cache,

 - return on null pointer in print_lock_dependencies,

 - one more lockdep return with 0 with unlocking fix in mark_lock.
Signed-off-by: NJarek Poplawski <jarkao2@o2.pl>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Here are mainly some lockdep returns with 0 with unlocking fixes.
Signed-off-by: NJarek Poplawski <jarkao2@o2.pl>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

paride_register() returns 1 on success, 0 on failure and module init
code looks like

	static int __init foo_init(void)
	{
		return paride_register(&foo) - 1;
	}

which is not what one get used to. Converted to usual 0/-E convention.

In case of kbic driver, unwind registration. It was just

	return (paride_register(&k951)||paride_register(&k971))-1;
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We're about to change the semantics of pi_register()'s return value, so
rename it to something else first, so that any unconverted code reliaby
breaks.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

<quote Imre Deak from Thu, 12 Jan 2006 21:18:54 +0200>
  In order for spi_busnum_to_master to work spi master devices must be linked
  into the spi_master_class.subsys.kset list.  At the moment the default
  class_obj_subsys.kset is used and we can't enumerate the master devices.
</quote>
Signed-off-by: NHans-Christian Egtvedt <hcegtvedt@atmel.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Correct the following in driver/spi/spi.c in function spi_busnum_to_master:

 * must allow bus_num 0, the if is really not needed.
 * correct the name buffer which is too small for bus_num >= 10000. It

should be 9 bytes big, not 8.
Signed-off-by: NHans-Christian Egtvedt <hcegtvedt@atmel.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

lock_super() is unnecessary for setting super-block feature flags.  Use the
provided *_SET_COMPAT_FEATURE() macros as well.
Signed-off-by: NAndreas Gruenbacher <agruen@suse.de>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

A couple of minor code simplifications to the kernel/cpuset.c code.  No
functional change.  Just a little less code and a little more readable.
Signed-off-by: NPaul Jackson <pj@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

linux/cdev.h uses struct kobject and other structs and should therefore
include them.  Currently, a module either needs to add the missing includes
itself, or, in case a module includes other headers already, needs to put
<linux/cdev.h> last, which goes against a alphabetically-sorted include
list.
Signed-off-by: NJan Engelhardt <jengelh@gmx.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

  rmmod/3080 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
   (proc_subdir_lock){--..}, at: [<c04a33b0>] remove_proc_entry+0x40/0x191

  and this task is already holding:
   (ide_lock){++..}, at: [<c05651a2>] ide_unregister_subdriver+0x39/0xc8
  which would create a new lock dependency:
   (ide_lock){++..} -> (proc_subdir_lock){--..}

  but this new dependency connects a hard-irq-safe lock:
   (ide_lock){++..}
  ... which became hard-irq-safe at:
    [<c043c458>] lock_acquire+0x4b/0x6b
    [<c06129d7>] _spin_lock_irqsave+0x22/0x32
    [<c0567870>] ide_intr+0x17/0x1a9
    [<c044eb31>] handle_IRQ_event+0x20/0x4d
    [<c044ebf2>] __do_IRQ+0x94/0xef
    [<c0406771>] do_IRQ+0x9e/0xbd

  to a hard-irq-unsafe lock:
   (proc_subdir_lock){--..}
  ... which became hard-irq-unsafe at:
  ...  [<c043c458>] lock_acquire+0x4b/0x6b
    [<c06126ab>] _spin_lock+0x19/0x28
    [<c04a32f2>] xlate_proc_name+0x1b/0x99
    [<c04a3547>] proc_create+0x46/0xdf
    [<c04a3642>] create_proc_entry+0x62/0xa5
    [<c07c1972>] proc_misc_init+0x1c/0x1d2
    [<c07c1844>] proc_root_init+0x4c/0xe9
    [<c07ad703>] start_kernel+0x294/0x3b3

Move ide_remove_proc_entries() out from under ide_lock; there is nothing
that indicates that this is needed.

In specific, the call to ide_add_proc_entries() is unprotected, and there
is nothing else in the file using the respective ->proc fields. Also the
lock order around destroy_proc_ide_interface() suggests this.

Alan sayeth:

  proc_ide_write_settings walks the setting list under ide_setting_sem, read
  ditto.  remove_proc_entry is doing proc side housekeeping.

  Looks fine to me, although that old code is such a mess anything could be
  going on.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Jeff noted that the via driver returned an error to an unsigned int in a
a case where errors are not permitted. Move the check down earlier so we
can handle it properly. Not as pretty but it works this way and avoids
hacking up ugly stuff in the legacy ide core.
Signed-off-by: NAlan Cox <alan@redhat.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

One of our test team hit a reiserfs_panic while running fsstress tests on
2.6.19-rc1.  The message looks like :

  REISERFS: panic(device Null superblock):
  reiserfs[5676]: assertion !(p->path_length != 1 ) failed at
  fs/reiserfs/stree.c:397:reiserfs_check_path: path not properly relsed.

The backtrace looked :

  kernel BUG in reiserfs_panic at fs/reiserfs/prints.c:361!
	.reiserfs_check_path+0x58/0x74
	.reiserfs_get_block+0x1444/0x1508
	.__block_prepare_write+0x1c8/0x558
	.block_prepare_write+0x34/0x64
	.reiserfs_prepare_write+0x118/0x1d0
	.generic_file_buffered_write+0x314/0x82c
	.__generic_file_aio_write_nolock+0x350/0x3e0
	.__generic_file_write_nolock+0x78/0xb0
	.generic_file_write+0x60/0xf0
	.reiserfs_file_write+0x198/0x2038
	.vfs_write+0xd0/0x1b4
	.sys_write+0x4c/0x8c
	syscall_exit+0x0/0x4

Upon debugging I found that the restart_transaction was not releasing
the path if the th->refcount was > 1.

/*static*/
int restart_transaction(struct reiserfs_transaction_handle *th,
                           			struct inode *inode, struct path *path)
{
	[...]

         /* we cannot restart while nested */
         if (th->t_refcount > 1) { <<- Path is not released in this case!
                 return 0;
         }

         pathrelse(path); <<- Path released here.
	[...]

This could happen in such a situation :

In reiserfs/inode.c: reiserfs_get_block() ::

      if (repeat == NO_DISK_SPACE || repeat == QUOTA_EXCEEDED) {
          /* restart the transaction to give the journal a chance to free
           ** some blocks.  releases the path, so we have to go back to
           ** research if we succeed on the second try
           */
          SB_JOURNAL(inode->i_sb)->j_next_async_flush = 1;

        -->>  retval = restart_transaction(th, inode, &path); <<--

  We are supposed to release the path, no matter we succeed or fail. But
if the th->refcount is > 1, the path is still valid. And,

          if (retval)
                   goto failure;
          repeat =
              _allocate_block(th, block, inode,
                             &allocated_block_nr, NULL, create);

If the above allocate_block fails with NO_DISK_SPACE or QUOTA_EXCEEDED,
we would have path which is not released.

         if (repeat != NO_DISK_SPACE && repeat != QUOTA_EXCEEDED) {
                   goto research;
         }
         if (repeat == QUOTA_EXCEEDED)
                   retval = -EDQUOT;
         else
                   retval = -ENOSPC;
         goto failure;
	[...]

       failure:
	[...]
         reiserfs_check_path(&path); << Panics here !

Attached here is a patch which could fix the issue.

fix reiserfs/inode.c : restart_transaction() to release the path in all
cases.

The restart_transaction() doesn't release the path when the the journal
handle has a refcount > 1.  This would trigger a reiserfs_panic() if we
encounter an -ENOSPC / -EDQUOT in reiserfs_get_block().
Signed-off-by: NSuzuki K P <suzuki@in.ibm.com>
Cc: "Vladimir V. Saveliev" <vs@namesys.com>
Cc: <reiserfs-dev@namesys.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Acked-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The new shared APM emulation just like its ARM and MIPS predecessors uses
pm_suspend() which was only exported on SH.  Move export to close to it's
definition where it really should be anyway.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Documentation update, adding references to CFQ scheduler and to another
document about selecting IO Schedulers.
Signed-off-by: NFilipe Lautert <filipe@icewall.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>