This patch fixes a race condition where in system used to hang or sometime
crash within minutes when kprobes are inserted on ISR routine and a task
routine.

The fix has been stress tested on i386, ia64, pp64 and on x86_64.  To
reproduce the problem insert kprobes on schedule() and do_IRQ() functions
and you should see hang or system crash.
Signed-off-by: NAnil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: NAnanth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: NPrasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch fixes a bug in kprobes's handling of a corner case on i386 and
x86_64.  On an SMP system, if one CPU unregisters a kprobe just after
another CPU hits that probepoint, kprobe_handler() on the latter CPU sees
that the kprobe has been unregistered, and attempts to let the CPU continue
as if the probepoint hadn't been hit.  The bug is that on i386 and x86_64,
we were neglecting to set the IP back to the beginning of the probed
instruction.  This could cause an oops or crash.

This bug doesn't exist on ppc64 and ia64, where a breakpoint instruction
leaves the IP pointing to the beginning of the instruction.  I don't know
about sparc64.  (Dave, could you please advise?)

This fix has been tested on i386 and x86_64 SMP systems.  To reproduce the
problem, set one CPU to work registering and unregistering a kprobe
repeatedly, and another CPU pounding the probepoint in a tight loop.
Acked-by: NPrasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: NJim Keniston <jkenisto@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch addresses a potential race condition for a case where Kprobe has
been removed right after another CPU has taken a break hit.

The way this is addressed here is when the CPU that has taken a break hit
does not find its corresponding kprobe, then we check to see if the
original instruction got replaced with other than break.  If it got
replaced with other than break instruction, then we continue to execute
from the replaced instruction, else if we find that it is still a break,
then we let the kernel handle this, as this might be the break instruction
inserted by other than kprobe(may be kernel debugger).
Signed-off-by: NAnil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch adds flags "ax" to .kprobe.text section.
Signed-off-by: NPrasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch contains the sparc64 architecture specific changes to prevent the
possible race conditions.
Signed-off-by: NPrasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch contains the ia64 architecture specific changes to prevent the
possible race conditions.
Signed-off-by: NPrasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch contains the ppc64 architecture specific changes to prevent the
possible race conditions.
Signed-off-by: NPrasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch contains the x86_64 architecture specific changes to prevent the
possible race conditions.
Signed-off-by: NPrasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch contains the i386 architecture specific changes to prevent the
possible race conditions.
Signed-off-by: NPrasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

There are possible race conditions if probes are placed on routines within the
kprobes files and routines used by the kprobes.  For example if you put probe
on get_kprobe() routines, the system can hang while inserting probes on any
routine such as do_fork().  Because while inserting probes on do_fork(),
register_kprobes() routine grabs the kprobes spin lock and executes
get_kprobe() routine and to handle probe of get_kprobe(), kprobes_handler()
gets executed and tries to grab kprobes spin lock, and spins forever.  This
patch avoids such possible race conditions by preventing probes on routines
within the kprobes file and routines used by kprobes.

I have modified the patches as per Andi Kleen's suggestion to move kprobes
routines and other routines used by kprobes to a seperate section
.kprobes.text.

Also moved page fault and exception handlers, general protection fault to
.kprobes.text section.

These patches have been tested on i386, x86_64 and ppc64 architectures, also
compiled on ia64 and sparc64 architectures.
Signed-off-by: NPrasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

I noticed a strange return value in smsc_ircc_init in
drivers/net/irda/smsc_ircc2.c in rc4-mm1.

When reaching the line "if (ircc_fir > 0 && ircc_sir > 0)", ret is 0.  So I
don't see the point of setting it to 0 in the "else" case.  >From what I
see in 2.6.12 it should probably be set to -ENODEV at the begining of the
"else" case.  The attached patch does this.

Note that I didn't actually see any breakage caused by this.
Signed-off-by: NBrice Goglin <Brice.Goglin@ens-lyon.org>
Cc: Dmitry Torokhov <dtor_core@ameritech.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

IRDA: smsc-ircc2 - do not over-use void * pointers, use specific
      types wherever possible.
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>
Cc: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

IRDA: smsc-ircc2 - use netdev_priv() instead of accessing pointer
      directly.
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>
Cc: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

IRDA: smsc-ircc2 - add sysfs support (platform device and driver) and
      switch power management to the new scheme.
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>
Cc: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

IRDA: smsc-ircc2 - cleanup - do not pass around iobase, it can be
      retrieved from smsc_ircc_cb structure.
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>
Cc: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

IRDA: smsc-ircc2 - remove excessive typedefs.
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>
Cc: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

IRDA: smsc-ircc2 - remove home-grown DIM macro, use ARRAY_SIZE intead.
      Also fix out-of-bound array access.
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>
Cc: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

IRDA: smsc-ircc2 - some formatting changes for better readability.
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>
Cc: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

IRDA: smsc-ircc2 - whitespace fixes.
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>
Cc: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

  attached patch should fix the following race:
     Proc 1                               Proc 2

     __flush_batch()
       ll_rw_block()
                                        do_get_write_access()
					   lock_buffer
                                             jh is only waiting for checkpoint
					     -> b_transaction == NULL ->
					     do nothing
                                           unlock_buffer
    test_set_buffer_locked()
    test_clear_buffer_dirty()
                                           __journal_file_buffer()
                                        change the data
    submit_bh()

and we have sent wrong data to disk...  We now clean the dirty buffer flag
under buffer lock in all cases and hence we know that whenever a buffer is
starting to be journaled we either finish the pending write-out before
attaching a buffer to a transaction or we won't write the buffer until the
transaction is going to be committed.

The test in jbd_unexpected_dirty_buffer() is redundant - remove it.
Furthermore we have to clear the buffer dirty bit under the buffer lock to
prevent races with buffer write-out (and hence prevent returning a buffer with
IO happening).
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Use block layer predefined function.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We need to be sure that current data are sent to disk.  Hence we call
ll_rw_block() with SWRITE.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We need to be sure that current data in buffer are sent to disk.  Hence we
need to call ll_rw_block() with SWRITE.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We must be sure that the current data in buffer are sent to disk.  Hence we
have to call ll_rw_block() with SWRITE.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Introduce new ll_rw_block() operation SWRITE meaning that block layer should
wait for the buffer lock and write-out afterwards.  Hence data in buffers at
the time of call are guaranteed to be submitted to the disk.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix race between journal_commit_transaction() and other places as
journal_unmap_buffer() that are adding buffers to transaction's t_forget list.
 We have to protect against such places by holding j_list_lock even when
traversing the t_forget list.  The fact that other places can only add buffers
to the list makes the locking easier.  OTOH the lock ranking complicates the
stuff...
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

It seems that kjournald() may be missing a check of the JFS_UNMOUNT flag
before calling schedule().  This showed up in testing of OCFS2 recovery
where our recovery thread would hang in journal_kill_thread() called from
journal_destroy() because kjournald never got a chance to read the flag to
shut down before the schedule().

Zach pointed out the missing check which led me to hack up this trivial
patch.  It's been tested many times now and I have yet to reproduce the
hang, which was happening very regularly before.

<mild rant>
I'm guessing that we could really use some wait_event() calls with helper
functions in, well, most of jbd these days which would make a ton of the
wait code there vastly cleaner.
</mild rant>

As for why this doesn't happen in ext3 (or OCFS2 during normal
mount/unmount of the local nodes journal), I think it may that the specific
timing of events in the ocfs2 recovery thread exposes a race there.
Because ocfs2_replay_journal() is only interested in playing back the
journal, initialization and shutdown happen very quicky with no other
metadata put into that specific journal.
Acked-by: N"Stephen C. Tweedie" <sct@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add MMC/SD write protection switch handling for the Corgi platform
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add keyboard and touchscreen device definitions for corgi.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The corgi keyboard has need of a switch event type with slightly type to the
input system as recommended by the input maintainer.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Cc: Vojtech Pavlik <vojtech@suse.cz>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch moves the platform specific Sharp SL-C7x0 LCD code from the
w100fb driver into a more appropriate place and updates the Corgi code to
match the new w100fb driver.

It also updates the corgi touchscreen code to match the new simplified
interface available from w100fb.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The code w100fb was based on was horribly Sharp SL-C7x0 specific and there
was little else that could be done as I had no access to anything else with
a w100 in it.  There is no real documentation about this chipset available.

Ian Molton has access to other platforms with the w100 (Toshiba e-series)
and so between us, we've improved w100fb and made it platform independent.
Ian Molton also added support for the very similar w3220 and w3200
chipsets.

There are a lot of changes here and it nearly amounts to a rewrite of the
driver but it has been extensively tested and is being used in preference
to the original driver in the Zaurus community.  I'd therefore like to
update the mainline code to reflect this.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Acked-by: NAntonino Daplas <adaplas@pol.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Corgi Touchscreen bugfix.  If the PMU isn't running, the register needs to
be set to a sane value rather than reusing some random value.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Clean up some Corgi Touchscreen logic and merge the repeat calls to
w100fb_blanking() in anticipation of the w100fb patch.

Fix a pm_message_t reference.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The Corgi Touchscreen driver uses the PMU as an accurate timing source which
conflicts with its usage for performance monitoring.  This patch allows it to
be shared with other users such as oprofile.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The input system handles key state tracking so there's no need for the driver
to do so as well.  Also tidy up some comment formatting and remove a now
unneeded function.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add some power management code to the corgi keyboard driver so that only one
power event gets reported within any reasonable time frame and the driver
doesn't enter an infinte loop due to key repeat.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix a couple of compile errors in the corgi keyboard driver.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Only show the scr file in sysfs for SD cards.  Previously this was present
for all cards but had a contents of 0 for MMC cards.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add support for Secure Digital specific features in the wbsd driver.  Adds
support for read-only switch and wide bus transfers.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>