Linux 3.0.20
Some fixes
readahead: fix pipeline break caused by block plug

commit 3deaa7190a8da38453c4fabd9dec7f66d17fff67 upstream.

Herbert Poetzl reported a performance regression since 2.6.39.  The test
is a simple dd read, but with big block size.  The reason is:

T1: ra (A, A+128k), (A+128k, A+256k)
T2: lock_page for page A, submit the 256k
T3: hit page A+128K, ra (A+256k, A+384). the range isn't submitted
because of plug and there isn't any lock_page till we hit page A+256k
because all pages from A to A+256k is in memory
T4: hit page A+256k, ra (A+384, A+ 512). Because of plug, the range isn't
submitted again.
T5: lock_page A+256k, so (A+256k, A+512k) will be submitted. The task is
waitting for (A+256k, A+512k) finish.

There is no request to disk in T3 and T4, so readahead pipeline breaks.

We really don't need block plug for generic_file_aio_read() for buffered
I/O.  The readahead already has plug and has fine grained control when I/O
should be submitted.  Deleting plug for buffered I/O fixes the regression.

One side effect is plug makes the request size 256k, the size is 128k
without it.  This is because default ra size is 128k and not a reason we
need plug here.

Vivek said:

: We submit some readahead IO to device request queue but because of nested
: plug, queue never gets unplugged.  When read logic reaches a page which is
: not in page cache, it waits for page to be read from the disk
: (lock_page_killable()) and that time we flush the plug list.
:
: So effectively read ahead logic is kind of broken in parts because of
: nested plugging.  Removing top level plug (generic_file_aio_read()) for
: buffered reads, will allow unplugging queue earlier for readahead.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Reported-by: Herbert Poetzl <herbert@13thfloor.at>
Tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ALSA: HDA: Fix duplicated output to more than one codec

commit 54c2a89f60fd71b924d0f848ac892442951401a6 upstream.

This typo caused the wrong codec's nid to be checked for wcaps type.
As a result, sometimes speakers would duplicate the output sent to
HDMI output.

BugLink: https://bugs.launchpad.net/bugs/924320
Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	sound/pci/hda/hda_codec.c
ASoC: wm_hubs: Enable line out VMID buffer for single ended line outputs

commit 77231abe55433aa17eca712718745275853fa66d upstream.

For optimal performance the single ended line outputs require that the
line output VMID buffer be enabled.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	sound/soc/codecs/wm_hubs.c
ASoC: wm_hubs: fix wrong bits for LINEOUT2 N/P mixer

commit 114395c61ad2eb5a7a5cd163fcadb2414e48245a upstream.

Signed-off-by: UK KIM <w0806.kim@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM: 7306/1: vfp: flush thread hwstate before restoring context from sigframe

commit 2af276dfb1722e97b190bd2e646b079a2aa674db upstream.

Following execution of a signal handler, we currently restore the VFP
context from the ucontext in the signal frame. This involves copying
from the user stack into the current thread's vfp_hard_struct and then
flushing the new data out to the hardware registers.

This is problematic when using a preemptible kernel because we could be
context switched whilst updating the vfp_hard_struct. If the current
thread has made use of VFP since the last context switch, the VFP
notifier will copy from the hardware registers into the vfp_hard_struct,
overwriting any data that had been partially copied by the signal code.

Disabling preemption across copy_from_user calls is a terrible idea, so
instead we move the VFP thread flush *before* we update the
vfp_hard_struct. Since the flushing is performed lazily, this has the
effect of disabling VFP and clearing the CPU's VFP state pointer,
therefore preventing the thread from being updated with stale data on
the next context switch.

Tested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	arch/arm/kernel/signal.c
ARM: 7307/1: vfp: fix ptrace regset modification race

commit 247f4993a5974e6759606c4d380748eecfd273ff upstream.

In a preemptible kernel, vfp_set() can be preempted, causing the
hardware VFP context to be switched while the thread vfp state is
being read and modified.  This leads to a race condition which can
cause the thread vfp state to become corrupted if lazy VFP context
save occurs due to preemption in between the time thread->vfpstate
is read and the time the modified state is written back.

This may occur if preemption occurs during the execution of a
ptrace() call which modifies the VFP register state of a thread.
Such instances should be very rare in most realistic scenarios --
none has been reported, so far as I am aware.  Only uniprocessor
systems should be affected, since VFP context save is not currently
lazy in SMP kernels.

The problem was introduced by my earlier patch migrating to use
regsets to implement ptrace.

This patch does a vfp_sync_hwstate() before reading
thread->vfpstate, to make sure that the thread's VFP state is not
live in the hardware registers while the registers are modified.

Thanks to Will Deacon for spotting this.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	arch/arm/kernel/ptrace.c
ARM: 7308/1: vfp: flush thread hwstate before copying ptrace registers

commit 8130b9d7b9d858aa04ce67805e8951e3cb6e9b2f upstream.

If we are context switched whilst copying into a thread's
vfp_hard_struct then the partial copy may be corrupted by the VFP
context switching code (see "ARM: vfp: flush thread hwstate before
restoring context from sigframe").

This patch updates the ptrace VFP set code so that the thread state is
flushed before the copy, therefore disabling VFP and preventing
corruption from occurring.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM: OMAP2+: GPMC: fix device size setup

commit 8ef5d844cc3a644ea6f7665932a4307e9fad01fa upstream.

following statement can only change device size from 8-bit(0) to
16-bit(1),
but not vice versa:

regval |= GPMC_CONFIG1_DEVICESIZE(wval);

so as this field has 1 reserved bit, that could be used in future,
just clear both bits and then OR with the desired value

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	arch/arm/mach-omap2/gpmc.c
drivers/tty/vt/vt_ioctl.c: fix KDFONTOP 32bit compatibility layer

commit cbcb8346054073d000ecac324763372d6abd44ac upstream.

KDFONTOP(GET) currently fails with EIO when being run in a 32bit
userland
with a 64bit kernel if the font width is not 8.

This is because of the setting of the KD_FONT_FLAG_OLD flag, which makes
con_font_get return EIO in such case.

This flag should *not* be set for KDFONTOP, since it's actually the
whole
point of this flag (see comment in con_font_set for instance).

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Arthur Taylor <art@ified.ca>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	drivers/tty/vt/vt_ioctl.c
proc: mem_release() should check mm != NULL

commit 71879d3cb3dd8f2dfdefb252775c1b3ea04a3dd4 upstream.

mem_release() can hit mm == NULL, add the necessary check.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
proc: unify mem_read() and mem_write()

commit 572d34b946bae070debd42db1143034d9687e13f upstream.

No functional changes, cleanup and preparation.

mem_read() and mem_write() are very similar. Move this code into the
new common helper, mem_rw(), which takes the additional "int write"
argument.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	fs/proc/base.c
proc: make sure mem_open() doesn't pin the target's memory

commit 6d08f2c7139790c268820a2e590795cb8333181a upstream.

Once /proc/pid/mem is opened, the memory can't be released until
mem_release() even if its owner exits.

Change mem_open() to do atomic_inc(mm_count) + mmput(), this only
pins mm_struct. Change mem_rw() to do atomic_inc_not_zero(mm_count)
before access_remote_vm(), this verifies that this mm is still alive.

I am not sure what should mem_rw() return if atomic_inc_not_zero()
fails. With this patch it returns zero to match the "mm == NULL" case,
may be it should return -EINVAL like it did before e268337d.

Perhaps it makes sense to add the additional fatal_signal_pending()
check into the main loop, to ensure we do not hold this memory if
the target task was oom-killed.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
firewire: ohci: add reset packet quirk for SB Audigy

commit d1bb399ad03c11e792f6dea198d3b1e23061f094 upstream.

The Audigy's SB1394 controller is actually from Texas Instruments
and has the same bus reset packet generation bug, so it needs the
same quirk entry.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	drivers/firewire/ohci.c
firewire: ohci: disable MSI on Ricoh controllers

commit 320cfa6ce0b3dc794fedfa4bae54c0f65077234d upstream.

The PCIe device

    FireWire (IEEE 1394) [0c00]: Ricoh Co Ltd FireWire Host Controller
    [1180:e832] (prog-if 10 [OHCI])

is unable to access attached FireWire devices when MSI is enabled but
works if MSI is disabled.
http://www.mail-archive.com/alsa-user@lists.sourceforge.net/msg28251.html

Hence add the "disable MSI" quirks flag for this device, or in fact for
safety and simplicity for all current (R5U230, R5U231, R5U240) and
future Ricoh PCIe 1394 controllers.

Reported-by: Stefan Thomas <kontrapunktstefan@googlemail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
IB/mlx4: pass SMP vendor-specific attribute MADs to firmware

commit a6f7feae6d19e84253918d88b04153af09d3a243 upstream.

In the current code, vendor-specific MADs (e.g with the FDR-10
attribute) are silently dropped by the driver, resulting in timeouts
at the sending side and inability to query/configure the relevant
feature.  However, the ConnectX firmware is able to handle such MADs.
For unsupported attributes, the firmware returns a GET_RESPONSE MAD
containing an error status.

For example, for a FDR-10 node with LID 11:

    # ibstat mlx4_0 1

    CA: 'mlx4_0'
    Port 1:
    State: Active
    Physical state: LinkUp
    Rate: 40 (FDR10)
    Base lid: 11
    LMC: 0
    SM lid: 24
    Capability mask: 0x02514868
    Port GUID: 0x0002c903002e65d1
    Link layer: InfiniBand

Extended Port Query (EPI) vendor mad timeouts before the patch:

    # smpquery MEPI 11 -d

    ibwarn: [4196] smp_query_via: attr 0xff90 mod 0x0 route Lid 11
    ibwarn: [4196] _do_madrpc: retry 1 (timeout 1000 ms)
    ibwarn: [4196] _do_madrpc: retry 2 (timeout 1000 ms)
    ibwarn: [4196] _do_madrpc: timeout after 3 retries, 3000 ms
    ibwarn: [4196] mad_rpc: _do_madrpc failed; dport (Lid 11)
    smpquery: iberror: [pid 4196] main: failed: operation EPI: ext port
info query failed

EPI query works OK with the patch:

    # smpquery MEPI 11 -d

    ibwarn: [6548] smp_query_via: attr 0xff90 mod 0x0 route Lid 11
    ibwarn: [6548] mad_rpc: data offs 64 sz 64
    mad data
    0000 0000 0000 0001 0000 0001 0000 0001
    0000 0000 0000 0000 0000 0000 0000 0000
    0000 0000 0000 0000 0000 0000 0000 0000
    0000 0000 0000 0000 0000 0000 0000 0000
    # Ext Port info: Lid 11 port 0
    StateChangeEnable:...............0x00
    LinkSpeedSupported:..............0x01
    LinkSpeedEnabled:................0x01
    LinkSpeedActive:.................0x01

Signed-off-by: Jack Morgenstein <jackm@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Acked-by: Ira Weiny <weiny2@llnl.gov>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	drivers/infiniband/hw/mlx4/mad.c
kprobes: fix a memory leak in function pre_handler_kretprobe()

commit 55ca6140e9bb307efc97a9301a4f501de02a6fd6 upstream.

In function pre_handler_kretprobe(), the allocated kretprobe_instance
object will get leaked if the entry_handler callback returns non-zero.
This may cause all the preallocated kretprobe_instance objects exhausted.

This issue can be reproduced by changing
samples/kprobes/kretprobe_example.c to probe "mutex_unlock".  And the fix
is straightforward: just put the allocated kretprobe_instance object back
onto the free_instances list.

[akpm@linux-foundation.org: use raw_spin_lock/unlock]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
at_hdmac: bugfix for enabling channel irq

commit bda3a47c886664e86ee14eb79e9072b9e341f575 upstream.

commit 463894705e4089d0ff69e7d877312d496ac70e5b deleted redundant
chan_id and chancnt initialization in dma drivers as this is done
in dma_async_device_register().

However, atc_enable_irq() relied on chan_id set before registering
the device, what left only channel 0 functional for this driver.

This patch introduces atc_enable/disable_chan_irq() as a variant
of atc_enable/disable_irq() with the channel as explicit argument.

Signed-off-by: Nikolaus Voss <n.voss@weinmann.de>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	drivers/dma/at_hdmac.c
	drivers/dma/at_hdmac_regs.h
mm/filemap_xip.c: fix race condition in xip_file_fault()

commit 99f02ef1f18631eb0a4e0ea0a3d56878dbcb4b90 upstream.

Fix a race condition that shows in conjunction with xip_file_fault()
when
two threads of the same user process fault on the same memory page.

In this case, the race winner will install the page table entry and the
unlucky loser will cause an oops: xip_file_fault calls vm_insert_pfn
(via
vm_insert_mixed) which drops out at this check:

	retval = -EBUSY;
	if (!pte_none(*pte))
		goto out_unlock;

The resulting -EBUSY return value will trigger a BUG_ON() in
xip_file_fault.

This fix simply considers the fault as fixed in this case, because the
race winner has successfully installed the pte.

[akpm@linux-foundation.org: use conventional (and consistent) comment
layout]
Reported-by: David Sadler <dsadler@us.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Reported-by: Louis Alex Eisner <leisner@cs.ucsd.edu>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	mm/filemap_xip.c