smatch detected the following issue:
drivers/net/can/usb/gs_usb.c:904 gs_usb_probe() error:
   potential null dereference 'dev'.  (kzalloc returns null)

Add a check for null return from kzalloc and return -ENOMEM
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

USB endpoint's wMaxPacketSize field is an le16 entity. Use
appropriate le16_to_cpu macros to maintain endian independence.
Reported-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Ahmed S. Darwish <ahmed.darwish@valeo.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Current driver code arbitrarily assumes a max outstanding tx
value of 16 parallel transmissions. Meanwhile, the device
firmware provides its actual maximum inside its reply to the
CMD_GET_SOFTWARE_INFO message.

Under heavy tx traffic, if the interleaved transmissions count
increases above the limit reported by firmware, the firmware
breaks up badly, reports a massive list of internal errors, and
the candump traces hardly matches the actual frames sent and
received.

On the other hand, in certain models, the firmware can support
up to 48 tx URBs instead of just 16, increasing the driver
throughput by two-fold and reducing the possibility of -ENOBUFs.

Thus dynamically set the driver's max tx URBs value according
to firmware replies.
Signed-off-by: Ahmed S. Darwish <ahmed.darwish@valeo.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

When the device is powered up, some (older) firmware versions fail to work
properly if we send commands before the boot is complete (everything is OK
when the device is hot-plugged). The firmware indicates its ready status by
putting the link up.
Newer firmwares delay the first command so they don't suffer from this problem.
They also report the link being always up.

Wait for firmware to become ready (link up) before sending any commands and/or
data.

This also allows lowering CMD_TIMEOUT value to a reasonable time.

Tested with 4.1.0.9 (old) and 4.1.0.30 (new) firmware versions.
Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Cc: stable@vger.kernel.org # v3.19
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit db31c55a (net: clamp ->msg_namelen instead of returning an
error) introduced the clamping of msg_namelen when the unsigned value
was larger than sizeof(struct sockaddr_storage). This caused a
msg_namelen of -1 to be valid. The native code was subsequently fixed by
commit dbb490b9 (net: socket: error on a negative msg_namelen).

In addition, the native code sets msg_namelen to 0 when msg_name is
NULL. This was done in commit (6a2a2b3a net:socket: set msg_namelen
to 0 if msg_name is passed as NULL in msghdr struct from userland) and
subsequently updated by 08adb7da (fold verify_iovec() into
copy_msghdr_from_user()).

This patch brings the get_compat_msghdr() in line with
copy_msghdr_from_user().

Fixes: db31c55a (net: clamp ->msg_namelen instead of returning an error)
Cc: David S. Miller <davem@davemloft.net>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Sathya Perla says:

====================
be2net: patch set

Hi David, this patch set includes 3 bug fixes to the be2net driver.

Patch 1 fixes a vlan isolation issue with VFs. When a VF is placed in
promiscous mode, it could receive packets belonging to any vlan, as
the PF driver grants vlan promisc capability to VFs. The PF
driver now disables the vlan promisc capability for VFs to fix this
problem.

Patch 2 fixes the call to MODIFY_EQ_DELAY FW cmd to not include more
than 8 EQs per cmd. The FW is not capable of handling more than 8 EQs
per cmd.

Patch 3 fixes an EEH error detection issue. On Power platforms,
when an EEH error occurs, the slot disconnect state is more reliably
detected via an MMIO read compared to a config read. So, the error
register reads that occur every second are now done via MMIO.

Pls apply this patch set to the "net" tree. Thanks!
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

When an EEH error occurs, the device/slot is disconnected. This condition
is more reliably detected (i.e., returns all ones) with an MMIO read rather
than a config read -- especially on power platforms.

Hence, this patch fixes EEH error detection by replacing config reads with
MMIO reads for reading the error registers. The error registers in
Skyhawk-R/BE2/BE3 are accessible both via the config space and the
PCICFG (BAR0) memory space.
Reported-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Suresh Reddy <Suresh.Reddy@emulex.com>
Signed-off-by: Sathya Perla <sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Issuing this cmd for more than 8 EQs does not have the intended effect
even on BEx and Skyhawk-R.

This patch fixes this by issuing this cmd for upto 8 EQs at a time.
Signed-off-by: Suresh Reddy <Suresh.Reddy@emulex.com>
Signed-off-by: Sathya Perla <sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently, a PF does not restrict its VF interface from enabling vlan
promiscuous mode. This breaks vlan isolation when a vlan
(transparent tagging) is configured on a VF.

This patch fixes this problem by disabling the vlan promisc capability
for VFs.
Reported-by: Yoann Juet <veilletechno-irts@univ-nantes.fr>
Signed-off-by: Vasundhara Volam <vasundhara.volam@emulex.com>
Signed-off-by: Sathya Perla <sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tcp_send_fin() does not account for the memory it allocates properly, so
sk_forward_alloc can be negative in cases where we've sent a FIN:

ss example output (ss -amn | grep -B1 f4294):
tcp    FIN-WAIT-1 0      1            192.168.0.1:45520         192.0.2.1:8080
	skmem:(r0,rb87380,t0,tb87380,f4294966016,w1280,o0,bl0)
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

for throw routes to trigger evaluation of other policy rules
EAGAIN needs to be propagated up to fib_rules_lookup
similar to how its done for IPv4

A simple testcase for verification is:

ip -6 rule add lookup 33333 priority 33333
ip -6 route add throw 2001:db8::1
ip -6 route add 2001:db8::1 via fe80::1 dev wlan0 table 33333
ip route get 2001:db8::1
Signed-off-by: Steven Barth <cyrus@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

On a MIPS Malta board, tons of fifo underflow errors have been observed
when using u-boot as bootloader instead of YAMON. The reason for that
is that YAMON used to set the pcnet device to SRAM mode but u-boot does
not. As a result, the default Tx threshold (64 bytes) is now too small to
keep the fifo relatively used and it can result to Tx fifo underflow errors.
As a result of which, it's best to setup the SRAM on supported controllers
so we can always use the NOUFLO bit.

Cc: <netdev@vger.kernel.org>
Cc: <stable@vger.kernel.org>
Cc: <linux-kernel@vger.kernel.org>
Cc: Don Fry <pcnet32@frontier.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Matt Grant reported frequent crashes in ipv6_select_ident when
udp6_ufo_fragment is called from openvswitch on a skb that doesn't
have a dst_entry set.

ipv6_proxy_select_ident generates the frag_id without using the dst
associated with the skb.  This approach was suggested by Vladislav
Yasevich.

Fixes: 0508c07f ("ipv6: Select fragment id during UFO segmentation if not set.")
Cc: Vladislav Yasevich <vyasevic@redhat.com>
Reported-by: Matt Grant <matt@mattgrant.net.nz>
Tested-by: Matt Grant <matt@mattgrant.net.nz>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Vladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull input updates from Dmitry Torokhov:
 "An update to Synaptics driver that makes it usable with the 2015
  lineup from Lenovo"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Revert "Input: synaptics - use dmax in input_mt_assign_slots"
  Input: synaptics - remove X250 from the topbuttonpad list
  Input: synaptics - remove X1 Carbon 3rd gen from the topbuttonpad list
  Input: synaptics - re-route tracksticks buttons on the Lenovo 2015 series
  Input: synaptics - remove TOPBUTTONPAD property for Lenovos 2015
  Input: synaptics - retrieve the extended capabilities in query $10
  Input: synaptics - do not retrieve the board id on old firmwares
  Input: synaptics - handle spurious release of trackstick buttons
  Input: synaptics - fix middle button on Lenovo 2015 products
  Input: synaptics - skip quirks when post-2013 dimensions
  Input: synaptics - support min/max board id in min_max_pnpid_table
  Input: synaptics - remove obsolete min/max quirk for X240
  Input: synaptics - query min dimensions for fw v8.1
  Input: synaptics - log queried and quirked dimension values
  Input: synaptics - split synaptics_resolution(), query first

Pull fuse fixes from Miklos Szeredi:
 "This fixes bugs in zero-copy splice to the fuse device"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: explicitly set /dev/fuse file's private_data
  fuse: set stolen page uptodate
  fuse: notify: don't move pages

Pull overlayfs fixes from Miklos Szeredi:
 "This fixes minor issues with the multi-layer update in v4.0"

* 'overlayfs-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: upper fs should not be R/O
  ovl: check lowerdir amount for non-upper mount
  ovl: print error message for invalid mount options

Pull MMC fix from Ulf Hansson:
 "MMC core: fix error path in mmc_pwrseq_simple_alloc()"

* tag 'mmc-v4.0-rc4' of git://git.linaro.org/people/ulf.hansson/mmc:
  mmc: pwrseq_simple: fix error path in mmc_pwrseq_simple_alloc

Pull pin control fixes from Linus Walleij:
 "Here is a slew of pin control fixes I've accumulated for the v4.0
  kernel.  Nothing special, just driver fixes (mainly embedded Intel it
  seems) and a misunderstanding regarding the stub functions was
  reverted:

   - Fix up consumer return values on pin control stubs.
   - Four patches fixing up the interrupt handling and sleep context
     save in the Baytrail driver.
   - Make default output directions work properly in the Cherryview
     driver.
   - Fix interrupt locking in the AT91 driver.
   - Fix setting interrupt generating lines as input in the sunxi
     driver"

* tag 'pinctrl-v4.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: sun4i: GPIOs configured as irq must be set to input before reading
  pinctrl: at91: move lock/unlock_as_irq calls into request/release
  pinctrl: update direction_output function of cherryview driver
  pinctrl: baytrail: Save pin context over system sleep
  pinctrl: baytrail: Rework interrupt handling
  pinctrl: baytrail: Clear interrupt triggering from pins that are in GPIO mode
  pinctrl: baytrail: Relax GPIO request rules
  Revert "pinctrl: consumer: use correct retval for placeholder functions"

Pull two arch/nios2 fixes from Ley Foon Tan:
 - Remove ucontext.h from exported arch headers
 - nios2: mm: do not invoke OOM killer on kernel fault OOM

* tag 'nios2-fixes-v4.0-rc5' of git://git.rocketboards.org/linux-socfpga-next:
  nios2: mm: do not invoke OOM killer on kernel fault OOM
  nios2: Remove ucontext.h from exported arch headers

Pull IDE fix from David Miller:
 "Just one fix to convert a by-hand conversion of jiffies to msecs, from
  Nicholas McGuire"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide:
  ide_tape: convert jiffies with jiffies_to_msecs

Pull sparc fixes from David Miller:

 1) Some command cases of semtimedop() not even handled due to miscoded
    comparison on sparc64.  From Rob Gardner.

 2) Due to two bugs, /proc/kcore wan't working properly on sparc.

 3) Make sure fatal traps stop all running cpus, from Dave Kleikamp.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: Fix /proc/kcore
  sparc: semtimedop() unreachable due to comparison error
  sparc: io_64.h: Replace io function-link macros
  sparc64: fatal trap should stop all cpus
  arch: sparc: kernel: starfire.c: Remove unused function
  arch: sparc: kernel: traps_64.c: Remove some unused functions

Pull networking fixes from David Miller:

 1) Fix packet header offset calculation in _decode_session6(), from
    Hajime Tazaki.

 2) Fix route leak in error paths of xfrm_lookup(), from Huaibin Wang.

 3) Be sure to clear state properly when scans fail in iwlwifi mvm code,
    from Luciano Coelho.

 4) iwlwifi tries to stop scans that aren't actually running, also from
    Luciano Coelho.

 5) mac80211 should drop mesh frames that are not encrypted, fix from
    Bob Copeland.

 6) Add new device ID to b43 wireless driver for BCM432228 chips, from
    Rafał Miłecki.

 7) Fix accidental addition of members after variable sized array in
    struct tc_u_hnode, from WANG Cong.

 8) Don't re-enable interrupts until after we call napi_complete() in
    ibmveth and WIZnet drivers, frm Yongbae Park.

 9) Fix regression in vlan tag handling of fec driver, from Fugang Duan.

10) If a network namespace change fails during rtnl_newlink(), we don't
    unwind the device registry properly.

11) Fix two TCP regressions, from Neal Cardwell:
  - Don't allow snd_cwnd_cnt to accumulate huge values due to missing
    test in tcp_cong_avoid_ai().
  - Restore CUBIC back to advancing cwnd by 1.5x packets per RTT.

12) Fix performance regression in xne-netback involving push TX
    notifications, from David Vrabel.

13) __skb_tstamp_tx() can be called with a NULL sk pointer, do not
    dereference blindly.  From Willem de Bruijn.

14) Fix potential stack overflow in RDS protocol stack, from Arnd
    Bergmann.

15) VXLAN_VID_MASK used incorrectly in new remote checksum offload
    support of VXLAN driver.  Fix from Alexey Kodanev.

16) Fix too small netlink SKB allocation in inet_diag layer, from Eric
    Dumazet.

17) ieee80211_check_combinations() does not count interfaces correctly,
    from Andrei Otcheretianski.

18) Hardware feature determination in bxn2x driver references a piece of
    software state that actually isn't initialized yet, fix from Michal
    Schmidt.

19) inet_csk_wait_for_connect() needs a sched_annotate_sleep()
    annoation, from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (56 commits)
  Revert "net: cx82310_eth: use common match macro"
  net/mlx4_en: Set statistics bitmap at port init
  IB/mlx4: Saturate RoCE port PMA counters in case of overflow
  net/mlx4_en: Fix off-by-one in ethtool statistics display
  IB/mlx4: Verify net device validity on port change event
  act_bpf: allow non-default TC_ACT opcodes as BPF exec outcome
  Revert "smc91x: retrieve IRQ and trigger flags in a modern way"
  inet: Clean up inet_csk_wait_for_connect() vs. might_sleep()
  ip6_tunnel: fix error code when tunnel exists
  netdevice.h: fix ndo_bridge_* comments
  bnx2x: fix encapsulation features on 57710/57711
  mac80211: ignore CSA to same channel
  nl80211: ignore HT/VHT capabilities without QoS/WMM
  mac80211: ask for ECSA IE to be considered for beacon parse CRC
  mac80211: count interfaces correctly for combination checks
  isdn: icn: use strlcpy() when parsing setup options
  rxrpc: bogus MSG_PEEK test in rxrpc_recvmsg()
  caif: fix MSG_OOB test in caif_seqpkt_recvmsg()
  bridge: reset bridge mtu after deleting an interface
  can: kvaser_usb: Fix tx queue start/stop race conditions
  ...

The misc subsystem (which is used for /dev/fuse) initializes private_data to
point to the misc device when a driver has registered a custom open file
operation, and initializes it to NULL when a custom open file operation has
*not* been provided.

This subtle quirk is confusing, to the point where kernel code registers
*empty* file open operations to have private_data point to the misc device
structure. And it leads to bugs, where the addition or removal of a custom open
file operation surprisingly changes the initial contents of a file's
private_data structure.

So to simplify things in the misc subsystem, a patch [1] has been proposed to
*always* set the private_data to point to the misc device, instead of only
doing this when a custom open file operation has been registered.

But before this patch can be applied we need to modify drivers that make the
assumption that a misc device file's private_data is initialized to NULL
because they didn't register a custom open file operation, so they don't rely
on this assumption anymore. FUSE uses private_data to store the fuse_conn and
errors out if this is not initialized to NULL at mount time.

Hence, we now set a file's private_data to NULL explicitly, to be independent
of whatever value the misc subsystem initializes it to by default.

[1] https://lkml.org/lkml/2014/12/4/939Reported-by: Giedrius Statkevicius <giedriuswork@gmail.com>
Reported-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Tom Van Braeckel <tomvanbraeckel@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>

The current error-path code (when gpiod_get_index() reports
an error) can never free pwrseq->reset_gpios[0], but might
try to tree pwrseq->reset_gpios[-1], which has unfortunate
consequences.
Signed-off-by: NeilBrown <neil@brown.name>
Fixes: 934f1f48Acked-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reported-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>

Use jiffies_to_msecs for converting jiffies as it handles all of the corner
cases reliably and also helps readability. The printk format is fixed up
as jiffies_to_msecs returns unsigned int not unsigned long.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

This reverts commit 11ad714b because
it breaks cx82310_eth.

The custom USB_DEVICE_CLASS macro matches
bDeviceClass, bDeviceSubClass and bDeviceProtocol
but the common USB_DEVICE_AND_INTERFACE_INFO matches
bInterfaceClass, bInterfaceSubClass and bInterfaceProtocol instead, which are
not specified.
Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

/proc/kcore investigates the "System RAM" elements in /proc/iomem to
initialize it's memory tables.  Therefore we have to register them
before it tries to do so.  kcore uses device_initcall() so let's
use arch_initcall() for the registry.

Also we need ARCH_PROC_KCORE_TEXT to get the virtual addresses of
the kernel image correct.
Reported-by: David Ahern <david.ahern@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Or Gerlitz says:

====================
mlx4 driver fixes for 4.0-rc

Just few small fixes for the 4.0 rc cycle.

The fix from Moni addresses an issue from 4.0-rc1 so we
just need it for net.

Eran's fix for off-by-one should go to 3.19.y too.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Port statistics bitmap will now be initialized at port init.  Even before
starting the port, statistics are visible to the user and must be properly masked.
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

For RoCE ports, we set the u32 PMA values based on u64 HCA counters. In case of
overflow, according to the IB spec, we have to saturate a counter to its
max value, do that.

Fixes: c3779134 ('IB/mlx4: Support PMA counters for IBoE')
Signed-off-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

NUM_PORT_STATS was 9 instead of 10, which caused off-by-one bug when
displaying the statistics starting from tx_chksum_offload in ethtool.

Fixes: f8c6455b ('net/mlx4_en: Extend checksum offloading by CHECKSUM COMPLETE')
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Processing an event is done in a different context from the one when
the event was dispatched. This requires a check that the slave
net device is still valid when the event is being processed. The check is done
under the iboe lock which ensure correctness.

Fixes: a5750090 ('IB/mlx4: Add port aggregation support')
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull sound fixes from Takashi Iwai:
 "This is a collection of many small fixes.  Most of fixes are for ASoC
  drivers, including the fixes of wrong field usages for boolean kctls.

  In addition, there is a fix in ASoC core for adding proper locks for
  component lists, and a fix for a HD-audio regression by the previous
  mono channel fix"

* tag 'sound-4.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (24 commits)
  ALSA: hda - Treat stereo-to-mono mix properly
  ASoC: wm9713: Fix wrong value references for boolean kctl
  ASoC: wm9712: Fix wrong value references for boolean kctl
  ASoC: wm8960: Fix wrong value references for boolean kctl
  ASoC: wm8955: Fix wrong value references for boolean kctl
  ASoC: wm8904: Fix wrong value references for boolean kctl
  ASoC: wm8903: Fix wrong value references for boolean kctl
  ASoC: wm8731: Fix wrong value references for boolean kctl
  ASoC: wm2000: Fix wrong value references for boolean kctl
  ASoC: tas5086: Fix wrong value references for boolean kctl
  ASoC: pcm1681: Fix wrong value references for boolean kctl
  ASoC: es8238: Fix wrong value references for boolean kctl
  ASoC: cs4271: Fix wrong value references for boolean kctl
  ASoC: ak4641: Fix wrong value references for boolean kctl
  ASoC: adav80x: Fix wrong value references for boolean kctl
  ASoC: Fix component lists locking
  ASoC: Intel: remove conflicts when load/unload multiple firmware images
  ASoC: rt286: Change the DMI mapping for Dino
  ASoC: sgtl5000: remove useless register write clearing CHRGPUMP_POWERUP
  ASoC: fsl_ssi: Don't try to round-up for PM divisor calculation
  ...

Pull crypto fixes from Herbert Xu:
 "Fix a bug in the ARM XTS implementation that can cause failures in
  decrypting encrypted disks, and fix is a memory overwrite bug that can
  cause a crash which can be triggered from userspace"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: aesni - fix memory usage in GCM decryption
  crypto: arm/aes update NEON AES module to latest OpenSSL version

Pull livepatching fix from Jiri Kosina:

 - fix for potential race with module loading, from Petr Mladek.

   The race is very unlikely to be seen in real world and has been found
   by code inspection, but should be fixed for 4.0 anyway.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: Fix subtle race with coming and going modules

Pull HID fixes from Jiri Kosina:

 - fixes for pen pen proximity / touch events in wacom driver, from Ping
   Cheng and Benjamin Tissoires

 - two new device-specific quirks from Oliver Neukum and Forest
   Wilkinson

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
  HID: wacom: check for wacom->shared before following the pointer
  HID: tivo: enable all buttons on the TiVo Slide Pro remote
  HID: add ALWAYS_POLL quirk for a Logitech 0xc007
  HID: wacom: rely on actual touch down count to decide touch_down
  HID: wacom: do not send pen events before touch is up/forced out

On sun4i-a10, when GPIOs are configured as external interrupt the value for
them in the data register does not seem to get updated, so set their mux to
input (and restore afterwards) when reading the pin.

Missed edges seem to be buffered, so this does not introduce a race
condition.

I've also tested this on sun5i-a13 and sun7i-a20 and those do not seem to
be affected, the input value representation in the data register does seem
to correctly get updated to the actual pin value while in irq mode there.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

After importing multi-lower layer support, users could mount a r/o
partition as the left most lowerdir instead of using it as upperdir.
And a r/o upperdir may cause an error like

	overlayfs: failed to create directory ./workdir/work

during mount.

This patch check the *s_flags* of upper fs and return an error if
it is a r/o partition. The checking of *upper_mnt->mnt_sb->s_flags*
can be removed now.

This patch also remove

	/* FIXME: workdir is not needed for a R/O mount */

from ovl_fill_super() because:

1) for upper fs r/o case
Setting a r/o partition as upper is prevented, no need to care about
workdir in this case.

2) for "mount overlay -o ro" with a r/w upper fs case
Users could remount overlayfs to r/w in this case, so workdir should
not be omitted.
Signed-off-by: hujianyang <hujianyang@huawei.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>

Recently multi-lower layer mount support allow upperdir and workdir
to be omitted, then cause overlayfs can be mount with only one
lowerdir directory. This action make no sense and have potential risk.

This patch check the total number of lower directories to prevent
mounting overlayfs with only one directory.

Also, an error message is added to indicate lower directories exceed
OVL_MAX_STACK limit.
Signed-off-by: hujianyang <hujianyang@huawei.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>