Add a DT binding documentation for Mediatek JPEG Decoder of
MT2701 SoC.
Signed-off-by: NRick Chang <rick.chang@mediatek.com>
Signed-off-by: NMinghsiu Tsai <minghsiu.tsai@mediatek.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Those are useful formats that should be handled.
Signed-off-by: NThibault Saunier <thibault.saunier@osg.samsung.com>
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Acked-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

In the case of semi planar formats cb and cr are in the same plane
in memory, meaning that will be set to 'cb' whatever the format is,
and whatever the (packed) order of those components are.
Suggested-by: NNicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: NThibault Saunier <thibault.saunier@osg.samsung.com>
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Acked-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

tveeprom_hauppauge_analog() used to need the I2C adapter in
order to print debug messages. As it now uses pr_foo() facilities
since commit 6037b3ca ("[media] tveeprom: print log messages
using pr_foo()"), the first argument of the function is not
needed anymore.

So, get rid of it.
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

The new picture_aspect, cea861_vic and hdmi_vic fields were not documented,
even though the corresponding flags were.

Add documentation for these new fields.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

ad -> as

It won't bring about world peace, but every little bit helps :-)
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

The device driver platform is actually written to during registration,
for setting the owner field, so platform_driver_register() does not
take a const pointer:

drivers/media/platform/coda/imx-vdoa.c: In function 'vdoa_driver_init':
drivers/media/platform/coda/imx-vdoa.c:333:213: error: passing argument 1 of '__platform_driver_register' discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
 module_platform_driver(vdoa_driver);
In file included from drivers/media/platform/coda/imx-vdoa.c:22:0:
include/linux/platform_device.h:199:12: note: expected 'struct platform_driver *' but argument is of type 'const struct platform_driver *'
 extern int __platform_driver_register(struct platform_driver *,
            ^~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/media/platform/coda/imx-vdoa.c: In function 'vdoa_driver_exit':
drivers/media/platform/coda/imx-vdoa.c:333:626: error: passing argument 1 of 'platform_driver_unregister' discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]

Remove the modifier again.

Fixes: d2fe28fe ("[media] coda/imx-vdoa: constify structs")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

While testing with CONFIG_UBSAN, I got this warning:

drivers/media/i2c/tc358743.c: In function 'tc358743_probe':
drivers/media/i2c/tc358743.c:1930:1: error: the frame size of 2480 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]

The problem is that the i2c_rd8/wr8/rd16/... functions in this driver pass
a pointer to a local variable into a common function, and each call to one
of them adds another variable plus redzone to the stack.

I also noticed that the way this is done is broken on big-endian machines,
as we copy the registers in CPU byte order.

To address both those problems, I'm adding two helper functions for reading
a register of up to 32 bits with correct endianess and change all other
functions to use that instead. Just to be sure we don't get the problem
back with changed optimizations in gcc, I'm also marking the new functions
as 'noinline', although my tests with gcc-7 don't require that.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

mxl111sf uses a lot of kernel stack memory as it puts an i2c_client
structure on the stack:

drivers/media/usb/dvb-usb-v2/mxl111sf.c: In function 'mxl111sf_init':
drivers/media/usb/dvb-usb-v2/mxl111sf.c:953:1: error: the frame size of 1248 bytes is larger than 1152 bytes [-Werror=frame-larger-than=]

We can avoid doing this by open-coding the call to i2c_transfer()
instead of calling tveeprom_read(), and not passing an i2c_client
pointer to tveeprom_hauppauge_analog(), which would ignore that
anyway.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

The cx231xx_do_i2c_scan function needs a lot of stack because
it puts an i2c_client structure on it:

drivers/media/usb/cx231xx/cx231xx-i2c.c: In function 'cx231xx_do_i2c_scan':
drivers/media/usb/cx231xx/cx231xx-i2c.c:518:1: error: the frame size of 1248 bytes is larger than 1152 bytes [-Werror=frame-larger-than=]

This changes it to call i2c_transfer() directly instead, avoiding the
need for the structure.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

The driver uses a relatively large data structure on the stack, which
showed up on my radar as we get a warning with the "latent entropy"
GCC plugin:

drivers/media/usb/pvrusb2/pvrusb2-eeprom.c:153:1: error: the frame size of 1376 bytes is larger than 1152 bytes [-Werror=frame-larger-than=]

The warning is usually hidden as we raise the warning limit to 2048
when the plugin is enabled, but I'd like to lower that again in the
future, and making this function smaller helps to do that without
build regressions.

Further analysis shows that putting an 'i2c_client' structure on
the stack is not really supported, as the embedded 'struct device'
is not initialized here, and we are only saved by the fact that
the function that is called here does not use the pointer at all.

Fixes: d855497e ("V4L/DVB (4228a): pvrusb2 to kernel 2.6.18")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

It allows to simulate the behavior of hardware with such limitations or
to connect vivid to real hardware with such limitations.

Add the "allocators" module parameter option to let vivid use the
dma-contig instead of vmalloc.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NVincent Abriou <vincent.abriou@st.com>
Reviewed-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Tested-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Image Sensor Controller has an internal image processor.
It can convert raw format to the other formats, like
RGB565, YUV420P. A module parameter 'sensor_preferred'
is used to enable or disable the pipeline function.
Some v4l2 controls are added to tuning the image when
the pipeline function is enabled.
Signed-off-by: NSongjun Wu <songjun.wu@microchip.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Don't crash the Kernel for driver errors
Signed-off-by: NShilpa P <shilpapri@gmail.com>
Acked-by: NAllen Pais <allen.lkml@gmail.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

The File handle is not yet added in the vdev list.So no need to call
v4l2_fh_del(&ctx->fh)if it fails to create control.
Signed-off-by: NShailendra Verma <shailendra.v@samsung.com>
Reviewed-by: NFabien Dessenne <fabien.dessenne@st.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Linux 4.10

* tag 'v4.10': (1558 commits)
  Linux 4.10
  Fix missing sanity check in /dev/sg
  scsi: don't BUG_ON() empty DMA transfers
  ipv6: release dst on error in ip6_dst_lookup_tail
  printk: use rcuidle console tracepoint
  ARM: multi_v7_defconfig: enable Qualcomm RPMCC
  irda: Fix lockdep annotations in hashbin_delete().
  vxlan: fix oops in dev_fill_metadata_dst
  dccp: fix freeing skb too early for IPV6_RECVPKTINFO
  dpaa_eth: small leak on error
  packet: Do not call fanout_release from atomic contexts
  reset: fix shared reset triggered_count decrement on error
  ntb: ntb_hw_intel: link_poll isn't clearing the pending status properly
  ntb_transport: Pick an unused queue
  ntb: ntb_perf missing dmaengine_unmap_put
  NTB: ntb_transport: fix debugfs_remove_recursive
  Revert "nohz: Fix collision between tick and other hrtimers"
  vfs: fix uninitialized flags in splice_to_pipe()
  drm/radeon: Use mode h/vdisplay fields to hide out of bounds HW cursor
  ARM: 8658/1: uaccess: fix zeroing of 64-bit get_user()
  ...

What happens is that a write to /dev/sg is given a request with non-zero
->iovec_count combined with zero ->dxfer_len.  Or with ->dxferp pointing
to an array full of empty iovecs.

Having write permission to /dev/sg shouldn't be equivalent to the
ability to trigger BUG_ON() while holding spinlocks...

Found by Dmitry Vyukov and syzkaller.

[ The BUG_ON() got changed to a WARN_ON_ONCE(), but this fixes the
  underlying issue.  - Linus ]
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Don't crash the machine just because of an empty transfer. Use WARN_ON()
combined with returning an error.

Found by Dmitry Vyukov and syzkaller.

[ Changed to "WARN_ON_ONCE()". Al has a patch that should fix the root
  cause, but a BUG_ON() is not acceptable in any case, and a WARN_ON()
  might still be a cause of excessive log spamming.

  NOTE! If this warning ever triggers, we may end up leaking resources,
  since this doesn't bother to try to clean the command up. So this
  WARN_ON_ONCE() triggering does imply real problems. But BUG_ON() is
  much worse.

  People really need to stop using BUG_ON() for "this shouldn't ever
  happen". It makes pretty much any bug worse.     - Linus ]
Signed-off-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Cc: James Bottomley <jejb@linux.vnet.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If ip6_dst_lookup_tail has acquired a dst and fails the IPv4-mapped
check, release the dst before returning an error.

Fixes: ec5e3b0a ("ipv6: Inhibit IPv4-mapped src address on the wire.")
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull ARM SoC fixes from Arnd Bergmann:
 "Two more bugfixes that came in during this week:

   - a defconfig change to enable a vital driver used on some Qualcomm
     based phones. This was already queued for 4.11, but the maintainer
     asked to have it in 4.10 after all.

   - a regression fix for the reset controller framework, this got
     broken by a typo in the 4.10 merge window"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: multi_v7_defconfig: enable Qualcomm RPMCC
  reset: fix shared reset triggered_count decrement on error

Pull ARM fixes from Russell King:
 "A couple of fixes from Kees concerning problems he spotted with our
  user access support"

* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 8658/1: uaccess: fix zeroing of 64-bit get_user()
  ARM: 8657/1: uaccess: consistently check object sizes

Pull x86 fix from Thomas Gleixner:
 "Make the build clean by working around yet another GCC stupidity"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/vm86: Fix unused variable warning if THP is disabled

Pull locking fix from Thomas Gleixner:
 "Move the futex init function to core initcall so user mode helper does
  not run into an uninitialized futex syscall"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  futex: Move futex_init() to core_initcall

Pull timer fixes from Thomas Gleixner:
 "Two small fixes::

   - Prevent deadlock on the tick broadcast lock. Found and fixed by
     Mike.

   - Stop using printk() in the timekeeping debug code to prevent a
     deadlock against the scheduler"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timekeeping: Use deferred printk() in debug code
  tick/broadcast: Prevent deadlock on tick_broadcast_lock

Pull networking fixes from David Miller:

 1) Fix leak in dpaa_eth error paths, from Dan Carpenter.

 2) Use after free when using IPV6_RECVPKTINFO, from Andrey Konovalov.

 3) fanout_release() cannot be invoked from atomic contexts, from Anoob
    Soman.

 4) Fix bogus attempt at lockdep annotation in IRDA.

 5) dev_fill_metadata_dst() can OOP on a NULL dst cache pointer, from
    Paolo Abeni.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  irda: Fix lockdep annotations in hashbin_delete().
  vxlan: fix oops in dev_fill_metadata_dst
  dccp: fix freeing skb too early for IPV6_RECVPKTINFO
  dpaa_eth: small leak on error
  packet: Do not call fanout_release from atomic contexts

Use rcuidle console tracepoint because, apparently, it may be issued
from an idle CPU:

  hw-breakpoint: Failed to enable monitor mode on CPU 0.
  hw-breakpoint: CPU 0 failed to disable vector catch

  ===============================
  [ ERR: suspicious RCU usage.  ]
  4.10.0-rc8-next-20170215+ #119 Not tainted
  -------------------------------
  ./include/trace/events/printk.h:32 suspicious rcu_dereference_check() usage!

  other info that might help us debug this:

  RCU used illegally from idle CPU!
  rcu_scheduler_active = 2, debug_locks = 0
  RCU used illegally from extended quiescent state!
  2 locks held by swapper/0/0:
   #0:  (cpu_pm_notifier_lock){......}, at: [<c0237e2c>] cpu_pm_exit+0x10/0x54
   #1:  (console_lock){+.+.+.}, at: [<c01ab350>] vprintk_emit+0x264/0x474

  stack backtrace:
  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.10.0-rc8-next-20170215+ #119
  Hardware name: Generic OMAP4 (Flattened Device Tree)
    console_unlock
    vprintk_emit
    vprintk_default
    printk
    reset_ctrl_regs
    dbg_cpu_pm_notify
    notifier_call_chain
    cpu_pm_exit
    omap_enter_idle_coupled
    cpuidle_enter_state
    cpuidle_enter_state_coupled
    do_idle
    cpu_startup_entry
    start_kernel

This RCU warning, however, is suppressed by lockdep_off() in printk().
lockdep_off() increments the ->lockdep_recursion counter and thus
disables RCU_LOCKDEP_WARN() and debug_lockdep_rcu_enabled(), which want
lockdep to be enabled "current->lockdep_recursion == 0".

Link: http://lkml.kernel.org/r/20170217015932.11898-1-sergey.senozhatsky@gmail.comSigned-off-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reported-by: NTony Lindgren <tony@atomide.com>
Tested-by: NTony Lindgren <tony@atomide.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Russell King <rmk@armlinux.org.uk>
Cc: <stable@vger.kernel.org> [3.4+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch enables the Qualcomm RPM based Clock Controller present on
A-family boards.
Signed-off-by: NAndy Gross <andy.gross@linaro.org>
Acked-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

A nested lock depth was added to the hasbin_delete() code but it
doesn't actually work some well and results in tons of lockdep splats.

Fix the code instead to properly drop the lock around the operation
and just keep peeking the head of the hashbin queue.
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Tested-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull block layer fix from Jens Axboe:
 "A single fix for a lockdep splat reported by Thomas and Gabriel"

* 'for-linus' of git://git.kernel.dk/linux-block:
  cfq-iosched: don't call wbt_disable_default() with IRQs disabled

Since the commit 0c1d70af ("net: use dst_cache for vxlan device")
vxlan_fill_metadata_dst() calls vxlan_get_route() passing a NULL
dst_cache pointer, so the latter should explicitly check for
valid dst_cache ptr. Unfortunately the commit d71785ff ("net: add
dst_cache to ovs vxlan lwtunnel") removed said check.

As a result is possible to trigger a null pointer access calling
vxlan_fill_metadata_dst(), e.g. with:

ovs-vsctl add-br ovs-br0
ovs-vsctl add-port ovs-br0 vxlan0 -- set interface vxlan0 \
	type=vxlan options:remote_ip=192.168.1.1 \
	options:key=1234 options:dst_port=4789 ofport_request=10
ip address add dev ovs-br0 172.16.1.2/24
ovs-vsctl set Bridge ovs-br0 ipfix=@i -- --id=@i create IPFIX \
	targets=\"172.16.1.1:1234\" sampling=1
iperf -c 172.16.1.1 -u -l 1000 -b 10M -t 1 -p 1234

This commit addresses the issue passing to vxlan_get_route() the
dst_cache already available into the lwt info processed by
vxlan_fill_metadata_dst().

Fixes: d71785ff ("net: add dst_cache to ovs vxlan lwtunnel")
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the current DCCP implementation an skb for a DCCP_PKT_REQUEST packet
is forcibly freed via __kfree_skb in dccp_rcv_state_process if
dccp_v6_conn_request successfully returns.

However, if IPV6_RECVPKTINFO is set on a socket, the address of the skb
is saved to ireq->pktopts and the ref count for skb is incremented in
dccp_v6_conn_request, so skb is still in use. Nevertheless, it gets freed
in dccp_rcv_state_process.

Fix by calling consume_skb instead of doing goto discard and therefore
calling __kfree_skb.

Similar fixes for TCP:

fb7e2399 [TCP]: skb is unexpectedly freed.
0aea76d3 tcp: SYN packets are now
simply consumed
Signed-off-by: NAndrey Konovalov <andreyknvl@google.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull powerpc fix from Michael Ellerman:
 "One fix from Paul: we can not use the radix MMU under a hypervisor for
  now.

  Although the code checked if the processor supports radix, that is not
  sufficient"

* tag 'powerpc-4.10-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64: Disable use of radix under a hypervisor

Pull input fix from Dmitry Torokhov:
 "Just a single change to Elan touchpad driver to recognize a new ACPI
  ID"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: elan_i2c - add ELAN0605 to the ACPI table

Pull i2c fix from Wolfram Sang:
 "I2C has a revert to fix a regression"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  Revert "i2c: designware: detect when dynamic tar update is possible"

Pull MMC fix from Ulf Hansson:
 "Fix multi-bit bus width without high-speed mode for MMC"

* tag 'mmc-v4.10-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: core: fix multi-bit bus width without high-speed mode

Pull NTB bugfixes frfom Jon Mason:
 "NTB bug fixes to address a crash when unloading the ntb module, a DMA
  engine unmap leak, allowing the proper queue choice, and clearing the
  SKX irq bit"

* tag 'ntb-4.10-bugfixes' of git://github.com/jonmason/ntb:
  ntb: ntb_hw_intel: link_poll isn't clearing the pending status properly
  ntb_transport: Pick an unused queue
  ntb: ntb_perf missing dmaengine_unmap_put
  NTB: ntb_transport: fix debugfs_remove_recursive

This should be >= instead of > here.  It means that we don't increment
the free count enough so it becomes off by one.

Fixes: 9ad1a374 ("dpaa_eth: add support for DPAA Ethernet")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull "Reset controller fixes for v4.10" from Philipp Zabel:

- Remove erroneous negation of the error check of the reset function
  to decrement trigger_count in the error case, not on success. This
  fixes shared resets to actually only trigger once, as intended.

* tag 'reset-for-4.10-fixes' of https://git.pengutronix.de/git/pza/linux:
  reset: fix shared reset triggered_count decrement on error

Commit 66644982 ("packet: call fanout_release, while UNREGISTERING a
netdev"), unfortunately, introduced the following issues.

1. calling mutex_lock(&fanout_mutex) (fanout_release()) from inside
rcu_read-side critical section. rcu_read_lock disables preemption, most often,
which prohibits calling sleeping functions.

[  ] include/linux/rcupdate.h:560 Illegal context switch in RCU read-side critical section!
[  ]
[  ] rcu_scheduler_active = 1, debug_locks = 0
[  ] 4 locks held by ovs-vswitchd/1969:
[  ]  #0:  (cb_lock){++++++}, at: [<ffffffff8158a6c9>] genl_rcv+0x19/0x40
[  ]  #1:  (ovs_mutex){+.+.+.}, at: [<ffffffffa04878ca>] ovs_vport_cmd_del+0x4a/0x100 [openvswitch]
[  ]  #2:  (rtnl_mutex){+.+.+.}, at: [<ffffffff81564157>] rtnl_lock+0x17/0x20
[  ]  #3:  (rcu_read_lock){......}, at: [<ffffffff81614165>] packet_notifier+0x5/0x3f0
[  ]
[  ] Call Trace:
[  ]  [<ffffffff813770c1>] dump_stack+0x85/0xc4
[  ]  [<ffffffff810c9077>] lockdep_rcu_suspicious+0x107/0x110
[  ]  [<ffffffff810a2da7>] ___might_sleep+0x57/0x210
[  ]  [<ffffffff810a2fd0>] __might_sleep+0x70/0x90
[  ]  [<ffffffff8162e80c>] mutex_lock_nested+0x3c/0x3a0
[  ]  [<ffffffff810de93f>] ? vprintk_default+0x1f/0x30
[  ]  [<ffffffff81186e88>] ? printk+0x4d/0x4f
[  ]  [<ffffffff816106dd>] fanout_release+0x1d/0xe0
[  ]  [<ffffffff81614459>] packet_notifier+0x2f9/0x3f0

2. calling mutex_lock(&fanout_mutex) inside spin_lock(&po->bind_lock).
"sleeping function called from invalid context"

[  ] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:620
[  ] in_atomic(): 1, irqs_disabled(): 0, pid: 1969, name: ovs-vswitchd
[  ] INFO: lockdep is turned off.
[  ] Call Trace:
[  ]  [<ffffffff813770c1>] dump_stack+0x85/0xc4
[  ]  [<ffffffff810a2f52>] ___might_sleep+0x202/0x210
[  ]  [<ffffffff810a2fd0>] __might_sleep+0x70/0x90
[  ]  [<ffffffff8162e80c>] mutex_lock_nested+0x3c/0x3a0
[  ]  [<ffffffff816106dd>] fanout_release+0x1d/0xe0
[  ]  [<ffffffff81614459>] packet_notifier+0x2f9/0x3f0

3. calling dev_remove_pack(&fanout->prot_hook), from inside
spin_lock(&po->bind_lock) or rcu_read-side critical-section. dev_remove_pack()
-> synchronize_net(), which might sleep.

[  ] BUG: scheduling while atomic: ovs-vswitchd/1969/0x00000002
[  ] INFO: lockdep is turned off.
[  ] Call Trace:
[  ]  [<ffffffff813770c1>] dump_stack+0x85/0xc4
[  ]  [<ffffffff81186274>] __schedule_bug+0x64/0x73
[  ]  [<ffffffff8162b8cb>] __schedule+0x6b/0xd10
[  ]  [<ffffffff8162c5db>] schedule+0x6b/0x80
[  ]  [<ffffffff81630b1d>] schedule_timeout+0x38d/0x410
[  ]  [<ffffffff810ea3fd>] synchronize_sched_expedited+0x53d/0x810
[  ]  [<ffffffff810ea6de>] synchronize_rcu_expedited+0xe/0x10
[  ]  [<ffffffff8154eab5>] synchronize_net+0x35/0x50
[  ]  [<ffffffff8154eae3>] dev_remove_pack+0x13/0x20
[  ]  [<ffffffff8161077e>] fanout_release+0xbe/0xe0
[  ]  [<ffffffff81614459>] packet_notifier+0x2f9/0x3f0

4. fanout_release() races with calls from different CPU.

To fix the above problems, remove the call to fanout_release() under
rcu_read_lock(). Instead, call __dev_remove_pack(&fanout->prot_hook) and
netdev_run_todo will be happy that &dev->ptype_specific list is empty. In order
to achieve this, I moved dev_{add,remove}_pack() out of fanout_{add,release} to
__fanout_{link,unlink}. So, call to {,__}unregister_prot_hook() will make sure
fanout->prot_hook is removed as well.

Fixes: 66644982 ("packet: call fanout_release, while UNREGISTERING a netdev")
Reported-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NAnoob Soman <anoob.soman@citrix.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>