Set the return variable to an error code as done elsewhere in the function.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}

// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

Merge branch 'leds-fixes-for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds

Pull LED subsystem bugfix from Bryan Wu.

* 'leds-fixes-for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds:
  leds: pwm: Fix for deferred probe in DT booted mode

We need to make sure that the error code from devm_of_pwm_get() is the one
the module returns in case of failure.
Restructure the code to make this possible for DT booted case.
With this patch the driver can ask for deferred probing when the board is
booted with DT.
Fixes for example omap4-sdp board's keyboard backlight led.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>

In commit 7314e613 ("Fix a few incorrectly checked
[io_]remap_pfn_range() calls") the uio driver started more properly
checking the passed-in user mapping arguments against the size of the
actual uio driver data.

That in turn exposed that some driver authors apparently didn't realize
that mmap can only work on a page granularity, and had tried to use it
with smaller mappings, with the new size check catching that out.

So since it's not just the user mmap() arguments that can be confused,
make the uio mmap code also verify that the uio driver has the memory
allocated at page boundaries in order for mmap to work.  If the device
memory isn't properly aligned, we return

  [ENODEV]
    The fildes argument refers to a file whose type is not supported by mmap().

as per the open group documentation on mmap.
Reported-by: Holger Brunck <holger.brunck@keymile.com>
Acked-by: Greg KH <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull irq fixes from Thomas Gleixner:
 - Correction of fuzzy and fragile IRQ_RETVAL macro
 - IRQ related resume fix affecting only XEN
 - ARM/GIC fix for chained GIC controllers

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip: Gic: fix boot for chained gics
  irq: Enable all irqs unconditionally in irq_resume
  genirq: Correct fuzzy and fragile IRQ_RETVAL() definition

Pull scheduler fixes from Ingo Molnar:
 "Various smaller fixlets, all over the place"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/doc: Fix generation of device-drivers
  sched: Expose preempt_schedule_irq()
  sched: Fix a trivial typo in comments
  sched: Remove unused variable in 'struct sched_domain'
  sched: Avoid NULL dereference on sd_busy
  sched: Check sched_domain before computing group power
  MAINTAINERS: Update file patterns in the lockdep and scheduler entries

Pull perf fixes from Ingo Molnar:
 "Misc kernel and tooling fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools lib traceevent: Fix conversion of pointer to integer of different size
  perf/trace: Properly use u64 to hold event_id
  perf: Remove fragile swevent hlist optimization
  ftrace, perf: Avoid infinite event generation loop
  tools lib traceevent: Fix use of multiple options in processing field
  perf header: Fix possible memory leaks in process_group_desc()
  perf header: Fix bogus group name
  perf tools: Tag thread comm as overriden

Pull Xen bug-fixes from Konrad Rzeszutek Wilk:
 "Fixes to patches that went in this merge window along with a latent
  bug:
   - Fix lazy flushing in case m2p override fails.
   - Fix module compile issues with ARM/Xen
   - Add missing call to DMA map page for Xen SWIOTLB for ARM"

* tag 'stable/for-linus-3.13-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/gnttab: leave lazy MMU mode in the case of a m2p override failure
  xen/arm: p2m_init and p2m_lock should be static
  arm/xen: Export phys_to_mach to fix Xen module link errors
  swiotlb-xen: add missing xen_dma_map_page call

Pull spi fixes from Mark Brown:
 "A smattering of driver specific fixes here, including a bunch for a
  long standing common pattern in the error handling paths, and a fix
  for an embarrassing thinko in the new devm master registration code"

* tag 'spi-v3.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi/pxa2xx: Restore private register bits.
  spi/qspi: Fix qspi remove path.
  spi/qspi: cleanup pm_runtime error check.
  spi/qspi: set correct platform drvdata in ti_qspi_probe()
  spi/pxa2xx: add new ACPI IDs
  spi: core: invert success test in devm_spi_register_master
  spi: spi-mxs: fix reference leak to master in mxs_spi_remove()
  spi: bcm63xx: fix reference leak to master in bcm63xx_spi_remove()
  spi: txx9: fix reference leak to master in txx9spi_remove()
  spi: mpc512x: fix reference leak to master in mpc512x_psc_spi_do_remove()
  spi: rspi: use platform drvdata correctly in rspi_remove()
  spi: bcm2835: fix reference leak to master in bcm2835_spi_remove()

Pull networking updates from David Miller:
 "Here is a pile of bug fixes that accumulated while I was in Europe"

 1) In fixing kernel leaks to userspace during copying of socket
    addresses, we broke a case that used to work, namely the user
    providing a buffer larger than the in-kernel generic socket address
    structure.  This broke Ruby amongst other things.  Fix from Dan
    Carpenter.

 2) Fix regression added by byte queue limit support in 8139cp driver,
    from Yang Yingliang.

 3) The addition of MSG_SENDPAGE_NOTLAST buggered up a few sendpage
    implementations, they should just treat it the same as MSG_MORE.
    Fix from Richard Weinberger and Shawn Landden.

 4) Handle icmpv4 errors received on ipv6 SIT tunnels correctly, from
    Oussama Ghorbel.  In particular we should send an ICMPv6 unreachable
    in such situations.

 5) Fix some regressions in the recent genetlink fixes, in particular
    get the pmcraid driver to use the new safer interfaces correctly.
    From Johannes Berg.

 6) macvtap was converted to use a per-cpu set of statistics, but some
    code was still bumping tx_dropped elsewhere.  From Jason Wang.

 7) Fix build failure of xen-netback due to missing include on some
    architectures, from Andy Whitecroft.

 8) macvtap double counts received packets in statistics, fix from Vlad
    Yasevich.

 9) Fix various cases of using *_STATS_BH() when *_STATS() is more
    appropriate.  From Eric Dumazet and Hannes Frederic Sowa.

10) Pktgen ipsec mode doesn't update the ipv4 header length and checksum
    properly after encapsulation.  Fix from Fan Du.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (61 commits)
  net/mlx4_en: Remove selftest TX queues empty condition
  {pktgen, xfrm} Update IPv4 header total len and checksum after tranformation
  virtio_net: make all RX paths handle erors consistently
  virtio_net: fix error handling for mergeable buffers
  virtio_net: Fixed a trivial typo (fitler --> filter)
  netem: fix gemodel loss generator
  netem: fix loss 4 state model
  netem: missing break in ge loss generator
  net/hsr: Support iproute print_opt ('ip -details ...')
  net/hsr: Very small fix of comment style.
  MAINTAINERS: Added net/hsr/ maintainer
  ipv6: fix possible seqlock deadlock in ip6_finish_output2
  ixgbe: Make ixgbe_identify_qsfp_module_generic static
  ixgbe: turn NETIF_F_HW_L2FW_DOFFLOAD off by default
  ixgbe: ixgbe_fwd_ring_down needs to be static
  e1000: fix possible reset_task running after adapter down
  e1000: fix lockdep warning in e1000_reset_task
  e1000: prevent oops when adapter is being closed and reset simultaneously
  igb: Fixed Wake On LAN support
  inet: fix possible seqlock deadlocks
  ...

The pipe code was trying (and failing) to be very careful about freeing
the pipe info only after the last access, with a pattern like:

        spin_lock(&inode->i_lock);
        if (!--pipe->files) {
                inode->i_pipe = NULL;
                kill = 1;
        }
        spin_unlock(&inode->i_lock);
        __pipe_unlock(pipe);
        if (kill)
                free_pipe_info(pipe);

where the final freeing is done last.

HOWEVER.  The above is actually broken, because while the freeing is
done at the end, if we have two racing processes releasing the pipe
inode info, the one that *doesn't* free it will decrement the ->files
count, and unlock the inode i_lock, but then still use the
"pipe_inode_info" afterwards when it does the "__pipe_unlock(pipe)".

This is *very* hard to trigger in practice, since the race window is
very small, and adding debug options seems to just hide it by slowing
things down.

Simon originally reported this way back in July as an Oops in
kmem_cache_allocate due to a single bit corruption (due to the final
"spin_unlock(pipe->mutex.wait_lock)" incrementing a field in a different
allocation that had re-used the free'd pipe-info), it's taken this long
to figure out.

Since the 'pipe->files' accesses aren't even protected by the pipe lock
(we very much use the inode lock for that), the simple solution is to
just drop the pipe lock early.  And since there were two users of this
pattern, create a helper function for it.

Introduced commit ba5bb147 ("pipe: take allocation and freeing of
pipe_inode_info out of ->i_mutex").
Reported-by: Simon Kirby <sim@hostway.ca>
Reported-by: Ian Applegate <ia@cloudflare.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org   # v3.10+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Remove waiting for TX queues to become empty during selftest.
This check is not necessary for any purpose, and might put
the driver into an infinite loop.
Signed-off-by: Eugenia Emantayev <eugenia@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

commit a553e4a6 ("[PKTGEN]: IPSEC support")
tried to support IPsec ESP transport transformation for pktgen, but acctually
this doesn't work at all for two reasons(The orignal transformed packet has
bad IPv4 checksum value, as well as wrong auth value, reported by wireshark)

- After transpormation, IPv4 header total length needs update,
  because encrypted payload's length is NOT same as that of plain text.

- After transformation, IPv4 checksum needs re-caculate because of payload
  has been changed.

With this patch, armmed pktgen with below cofiguration, Wireshark is able to
decrypted ESP packet generated by pktgen without any IPv4 checksum error or
auth value error.

pgset "flag IPSEC"
pgset "flows 1"
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

receive mergeable now handles errors internally.
Do same for big and small packet paths, otherwise
the logic is too hard to follow.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Eric Dumazet noticed that if we encounter an error
when processing a mergeable buffer, we don't
dequeue all of the buffers from this packet,
the result is almost sure to be loss of networking.

Jason Wang noticed that we also leak a page and that we don't decrement
the rq buf count, so we won't repost buffers (a resource leak).

Fix both issues.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michael Dalton <mwdalton@google.com>
Reported-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull UML fixes from Richard Weinberger:
 "Fixes two regressions which got introduced this merge window"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: Build always with -mcmodel=large on 64bit
  um: Rename print_stack_trace to do_stack_trace

Pull ARM fixes from Russell King:
 "Some ARM fixes, the biggest of which is the fix for the signal return
  codes; this came up due to an interaction between the V7M nommu
  changes and the BE8 changes.  Dave Martin spotted that the kexec
  trampoline wasn't being correctly copied (in a way which allows
  Thumb-2 to work).

  I've also fixed a number of breakages on footbridge platforms as I've
  upgraded one of my machines to v3.12...  one which had a 1200 day
  uptime"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: 7907/1: lib: delay-loop: Add align directive to fix BogoMIPS calculation
  ARM: 7897/1: kexec: Use the right ISA for relocate_new_kernel
  ARM: 7895/1: signal: fix armv7-m build issue in sigreturn_codes.S
  ARM: footbridge: fix EBSA285 LEDs
  ARM: footbridge: fix VGA initialisation
  ARM: fix booting low-vectors machines
  ARM: dma-mapping: check DMA mask against available memory

On UML SUBARCH can be x86, x86_64 and i386 and if it is x86
we use uname -m to select a defconfig.
Therefore we can no longer use -mcmodel=large only if SUBARCH
is x86_64.
Reported-and-tested-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

We cannot use print_stack_trace because the name conflicts
with linux/stacktrace.h.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Richard Weinberger <richard@nod.at>

Currently mx53 (CortexA8) running at 1GHz reports:
Calibrating delay loop... 663.55 BogoMIPS (lpj=3317760)

Tom Evans verified that alignments of 0x0 and 0x8 run the two instructions of __loop_delay in one clock cycle (1 clock/loop), while alignments of 0x4 and 0xc take 3 clocks to run the loop twice. (1.5 clock/loop)

The original object code looks like this:

00000010 <__loop_const_udelay>:
  10:	e3e01000 	mvn	r1, #0
  14:	e51f201c 	ldr	r2, [pc, #-28]	; 0 <__loop_udelay-0x8>
  18:	e5922000 	ldr	r2, [r2]
  1c:	e0800921 	add	r0, r0, r1, lsr #18
  20:	e1a00720 	lsr	r0, r0, #14
  24:	e0822b21 	add	r2, r2, r1, lsr #22
  28:	e1a02522 	lsr	r2, r2, #10
  2c:	e0000092 	mul	r0, r2, r0
  30:	e0800d21 	add	r0, r0, r1, lsr #26
  34:	e1b00320 	lsrs	r0, r0, #6
  38:	01a0f00e 	moveq	pc, lr

0000003c <__loop_delay>:
  3c:	e2500001 	subs	r0, r0, #1
  40:	8afffffe 	bhi	3c <__loop_delay>
  44:	e1a0f00e 	mov	pc, lr

After adding the 'align 3' directive to __loop_delay (align to 8 bytes):

00000010 <__loop_const_udelay>:
  10:	e3e01000 	mvn	r1, #0
  14:	e51f201c 	ldr	r2, [pc, #-28]	; 0 <__loop_udelay-0x8>
  18:	e5922000 	ldr	r2, [r2]
  1c:	e0800921 	add	r0, r0, r1, lsr #18
  20:	e1a00720 	lsr	r0, r0, #14
  24:	e0822b21 	add	r2, r2, r1, lsr #22
  28:	e1a02522 	lsr	r2, r2, #10
  2c:	e0000092 	mul	r0, r2, r0
  30:	e0800d21 	add	r0, r0, r1, lsr #26
  34:	e1b00320 	lsrs	r0, r0, #6
  38:	01a0f00e 	moveq	pc, lr
  3c:	e320f000 	nop	{0}

00000040 <__loop_delay>:
  40:	e2500001 	subs	r0, r0, #1
  44:	8afffffe 	bhi	40 <__loop_delay>
  48:	e1a0f00e 	mov	pc, lr
  4c:	e320f000 	nop	{0}

, which now reports:
Calibrating delay loop... 996.14 BogoMIPS (lpj=4980736)

Some more test results:

On mx31 (ARM1136) running at 532 MHz, before the patch:
Calibrating delay loop... 351.43 BogoMIPS (lpj=1757184)

On mx31 (ARM1136) running at 532 MHz after the patch:
Calibrating delay loop... 528.79 BogoMIPS (lpj=2643968)

Also tested on mx6 (CortexA9) and on mx27 (ARM926), which shows the same
BogoMIPS value before and after this patch.
Reported-by: Tom Evans <tom_usenet@optusnet.com.au>
Suggested-by: Tom Evans <tom_usenet@optusnet.com.au>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Copying a function with memcpy() and then trying to execute the
result isn't trivially portable to Thumb.

This patch modifies the kexec soft restart code to copy its
assembler trampoline relocate_new_kernel() using fncpy() instead,
so that relocate_new_kernel can be in the same ISA as the rest of
the kernel without problems.
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Reported-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
Tested-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

After "ARM: signal: sigreturn_codes should be endian neutral to
work in BE8" commit, thumb only platforms, like armv7m, fails to
compile sigreturn_codes.S. The reason is that for such arch
values '.arm' directive and arm opcodes are not allowed.

Fix conditionally enables arm opcodes only if no CONFIG_CPU_THUMBONLY
defined and it uses .org instructions to keep sigreturn_codes
layout.
Suggested-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

- The LEDs register is write-only: it can't be read-modify-written.
- The LEDs are write-1-for-off not 0.
- The check for the platform was inverted.

Fixes: cf6856d6 ("ARM: mach-footbridge: retire custom LED code")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: stable@vger.kernel.org

"MAC filter" sounds more reasonable than "MAC fitler".
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Patch from developers of the alternative loss models, downloaded from:
   http://netgroup.uniroma2.it/twiki/bin/view.cgi/Main/NetemCLG

 "in case 2, of the switch we change the direction of the inequality to
  net_random()>clg->a3, because clg->a3 is h in the GE model and when h
  is 0 all packets will be lost."
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Patch from developers of the alternative loss models, downloaded from:
   http://netgroup.uniroma2.it/twiki/bin/view.cgi/Main/NetemCLG

 "In the case 1 of the switch statement in the if conditions we
   need to add clg->a4 to clg->a1, according to the model."
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

There is a missing break statement in the Gilbert Elliot loss model
generator which makes state machine behave incorrectly.

Reported-by: Martin Burri <martin.burri@ch.abb.com
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

This implements the rtnl_link_ops fill_info routine for HSR.
Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>

IPv6 stats are 64 bits and thus are protected with a seqlock. By not
disabling bottom-half we could deadlock here if we don't disable bh and
a softirq reentrantly updates the same mib.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jeff Kirsher says:

====================
Intel Wired LAN Driver Updates

This series contains updates to igb, e1000 and ixgbe.

Akeem provides a igb fix where WOL was being reported as supported on
some ethernet devices which did not have that capability.

Yanjun provides a fix for e1000 which is similar to a previous fix
for e1000e commit bb9e44d0 ("e1000e: prevent oops when adapter is
being closed and reset simultaneously"), where the same issue was
observed on the older e1000 cards.

Vladimir Davydov provides 2 e1000 fixes.  The first fixes a lockdep
warning e1000_down() tries to synchronously cancel e1000 auxiliary
works (reset_task, watchdog_task, phy_info_task and fifo_stall_task)
which take adapter->mutex in their handlers.  The second patch is to
fix a possible race condition where reset_task() would be running
after adapter down.

John provides 2 fixes for ixgbe.  First turns ixgbe_fwd_ring_down
to static and the second disables NETIF_F_HW_L2FW_DOFFLOAD by default
because it allows upper layer net devices to use queues in the hardware
to directly submit and receive skbs.

Mark Rustad provides a single patch for ixgbe to make
ixgbe_identify_qsfp_module_generic static to resolve compile
warnings.

v2: Drop igb patch "igb: Update queue reinit function to call dev_close
    when init of queues fails" from Carolyn, so that the solution can
    be re-worked based on feedback from David Miller.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

It's no good setting vga_base after the VGA console has been
initialised, because if we do that we get this:

Unable to handle kernel paging request at virtual address 000b8000
pgd = c0004000
[000b8000] *pgd=07ffc831, *pte=00000000, *ppte=00000000
0Internal error: Oops: 5017 [#1] ARM
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 3.12.0+ #49
task: c03e2974 ti: c03d8000 task.ti: c03d8000
PC is at vgacon_startup+0x258/0x39c
LR is at request_resource+0x10/0x1c
pc : [<c01725d0>]    lr : [<c0022b50>]    psr: 60000053
sp : c03d9f68  ip : 000b8000  fp : c03d9f8c
r10: 000055aa  r9 : 4401a103  r8 : ffffaa55
r7 : c03e357c  r6 : c051b460  r5 : 000000ff  r4 : 000c0000
r3 : 000b8000  r2 : c03e0514  r1 : 00000000  r0 : c0304971
Flags: nZCv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment kernel

which is an access to the 0xb8000 without the PCI offset required to
make it work.

Fixes: cc22b4c1 ("ARM: set vga memory base at run-time")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: <stable@vger.kernel.org>

Commit f6f91b0d (ARM: allow kuser helpers to be removed from the
vector page) required two pages for the vectors code.  Although the
code setting up the initial page tables was updated, the code which
allocates page tables for new processes wasn't, neither was the code
which tears down the mappings.  Fix this.

Fixes: f6f91b0d ("ARM: allow kuser helpers to be removed from the vector page")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: <stable@vger.kernel.org>

Some buses have negative offsets, which causes the DMA mask checks to
falsely fail.  Fix this by using the actual amount of memory fitted in
the system.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Correct a namespace complaint by making the function static
and moving the prototype into the .c file.
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

NETIF_F_HW_L2FW_DOFFLOAD allows upper layer net devices such
as macvlan to use queues in the hardware to directly submit and
receive skbs.

This creates a subtle change in the datapath though. One change
being the skb may no longer use the root devices qdisc.

Because users may not expect this we can't enable the feature
by default unless the hardware can offload all the software
functionality above it. So for now disable it by default and
let users opt in.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

When compiling with -Wstrict-prototypes gcc catches a static
I missed.

./ixgbe_main.c:4254: warning: no previous prototype for 'ixgbe_fwd_ring_down'
Reported-by: Phillip Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

On e1000_down(), we should ensure every asynchronous work is canceled
before proceeding. Since the watchdog_task can schedule other works
apart from itself, it should be stopped first, but currently it is
stopped after the reset_task. This can result in the following race
leading to the reset_task running after the module unload:

e1000_down_and_stop():			e1000_watchdog():
----------------------			-----------------

cancel_work_sync(reset_task)
					schedule_work(reset_task)
cancel_delayed_work_sync(watchdog_task)

The patch moves cancel_delayed_work_sync(watchdog_task) at the beginning
of e1000_down_and_stop() thus ensuring the race is impossible.

Cc: Tushar Dave <tushar.n.dave@intel.com>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

The patch fixes the following lockdep warning, which is 100%
reproducible on network restart:

======================================================
[ INFO: possible circular locking dependency detected ]
3.12.0+ #47 Tainted: GF
-------------------------------------------------------
kworker/1:1/27 is trying to acquire lock:
 ((&(&adapter->watchdog_task)->work)){+.+...}, at: [<ffffffff8108a5b0>] flush_work+0x0/0x70

but task is already holding lock:
 (&adapter->mutex){+.+...}, at: [<ffffffffa0177c0a>] e1000_reset_task+0x4a/0xa0 [e1000]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&adapter->mutex){+.+...}:
       [<ffffffff810bdb5d>] lock_acquire+0x9d/0x120
       [<ffffffff816b8cbc>] mutex_lock_nested+0x4c/0x390
       [<ffffffffa017233d>] e1000_watchdog+0x7d/0x5b0 [e1000]
       [<ffffffff8108b972>] process_one_work+0x1d2/0x510
       [<ffffffff8108ca80>] worker_thread+0x120/0x3a0
       [<ffffffff81092c1e>] kthread+0xee/0x110
       [<ffffffff816c3d7c>] ret_from_fork+0x7c/0xb0

-> #0 ((&(&adapter->watchdog_task)->work)){+.+...}:
       [<ffffffff810bd9c0>] __lock_acquire+0x1710/0x1810
       [<ffffffff810bdb5d>] lock_acquire+0x9d/0x120
       [<ffffffff8108a5eb>] flush_work+0x3b/0x70
       [<ffffffff8108b5d8>] __cancel_work_timer+0x98/0x140
       [<ffffffff8108b693>] cancel_delayed_work_sync+0x13/0x20
       [<ffffffffa0170cec>] e1000_down_and_stop+0x3c/0x60 [e1000]
       [<ffffffffa01775b1>] e1000_down+0x131/0x220 [e1000]
       [<ffffffffa0177c12>] e1000_reset_task+0x52/0xa0 [e1000]
       [<ffffffff8108b972>] process_one_work+0x1d2/0x510
       [<ffffffff8108ca80>] worker_thread+0x120/0x3a0
       [<ffffffff81092c1e>] kthread+0xee/0x110
       [<ffffffff816c3d7c>] ret_from_fork+0x7c/0xb0

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&adapter->mutex);
                               lock((&(&adapter->watchdog_task)->work));
                               lock(&adapter->mutex);
  lock((&(&adapter->watchdog_task)->work));

 *** DEADLOCK ***

3 locks held by kworker/1:1/27:
 #0:  (events){.+.+.+}, at: [<ffffffff8108b906>] process_one_work+0x166/0x510
 #1:  ((&adapter->reset_task)){+.+...}, at: [<ffffffff8108b906>] process_one_work+0x166/0x510
 #2:  (&adapter->mutex){+.+...}, at: [<ffffffffa0177c0a>] e1000_reset_task+0x4a/0xa0 [e1000]

stack backtrace:
CPU: 1 PID: 27 Comm: kworker/1:1 Tainted: GF            3.12.0+ #47
Hardware name: System manufacturer System Product Name/P5B-VM SE, BIOS 0501    05/31/2007
Workqueue: events e1000_reset_task [e1000]
 ffffffff820f6000 ffff88007b9dba98 ffffffff816b54a2 0000000000000002
 ffffffff820f5e50 ffff88007b9dbae8 ffffffff810ba936 ffff88007b9dbac8
 ffff88007b9dbb48 ffff88007b9d8f00 ffff88007b9d8780 ffff88007b9d8f00
Call Trace:
 [<ffffffff816b54a2>] dump_stack+0x49/0x5f
 [<ffffffff810ba936>] print_circular_bug+0x216/0x310
 [<ffffffff810bd9c0>] __lock_acquire+0x1710/0x1810
 [<ffffffff8108a5b0>] ? __flush_work+0x250/0x250
 [<ffffffff810bdb5d>] lock_acquire+0x9d/0x120
 [<ffffffff8108a5b0>] ? __flush_work+0x250/0x250
 [<ffffffff8108a5eb>] flush_work+0x3b/0x70
 [<ffffffff8108a5b0>] ? __flush_work+0x250/0x250
 [<ffffffff8108b5d8>] __cancel_work_timer+0x98/0x140
 [<ffffffff8108b693>] cancel_delayed_work_sync+0x13/0x20
 [<ffffffffa0170cec>] e1000_down_and_stop+0x3c/0x60 [e1000]
 [<ffffffffa01775b1>] e1000_down+0x131/0x220 [e1000]
 [<ffffffffa0177c12>] e1000_reset_task+0x52/0xa0 [e1000]
 [<ffffffff8108b972>] process_one_work+0x1d2/0x510
 [<ffffffff8108b906>] ? process_one_work+0x166/0x510
 [<ffffffff8108ca80>] worker_thread+0x120/0x3a0
 [<ffffffff8108c960>] ? manage_workers+0x2c0/0x2c0
 [<ffffffff81092c1e>] kthread+0xee/0x110
 [<ffffffff81092b30>] ? __init_kthread_worker+0x70/0x70
 [<ffffffff816c3d7c>] ret_from_fork+0x7c/0xb0
 [<ffffffff81092b30>] ? __init_kthread_worker+0x70/0x70

== The issue background ==

The problem occurs, because e1000_down(), which is called under
adapter->mutex by e1000_reset_task(), tries to synchronously cancel
e1000 auxiliary works (reset_task, watchdog_task, phy_info_task,
fifo_stall_task), which take adapter->mutex in their handlers. So the
question is what does adapter->mutex protect there?

The adapter->mutex was introduced by commit 0ef4ee ("e1000: convert to
private mutex from rtnl") as a replacement for rtnl_lock() taken in the
asynchronous handlers. It targeted on fixing a similar lockdep warning
issued when e1000_down() was called under rtnl_lock(), and it fixed it,
but unfortunately it introduced the lockdep warning described above.
Anyway, that said the source of this bug is that the asynchronous works
were made to take rtnl_lock() some time ago, so let's look deeper and
find why it was added there.

The rtnl_lock() was added to asynchronous handlers by commit 338c15
("e1000: fix occasional panic on unload") in order to prevent
asynchronous handlers from execution after the module is unloaded
(e1000_down() is called) as it follows from the comment to the commit:

> Net drivers in general have an issue where timers fired
> by mod_timer or work threads with schedule_work are running
> outside of the rtnl_lock.
>
> With no other lock protection these routines are vulnerable
> to races with driver unload or reset paths.
>
> The longer term solution to this might be a redesign with
> safer locks being taken in the driver to guarantee no
> reentrance, but for now a safe and effective fix is
> to take the rtnl_lock in these routines.

I'm not sure if this locking scheme fixed the problem or just made it
unlikely, although I incline to the latter. Anyway, this was long time
ago when e1000 auxiliary works were implemented as timers scheduling
real work handlers in their routines. The e1000_down() function only
canceled the timers, but left the real handlers running if they were
running, which could result in work execution after module unload.
Today, the e1000 driver uses sane delayed works instead of the pair
timer+work to implement its delayed asynchronous handlers, and the
e1000_down() synchronously cancels all the works so that the problem
that commit 338c15 tried to cope with disappeared, and we don't need any
locks in the handlers any more. Moreover, any locking there can
potentially result in a deadlock.

So, this patch reverts commits 0ef4ee and 338c15.

Fixes: 0ef4eedc ("e1000: convert to private mutex from rtnl")
Fixes: 338c15e4 ("e1000: fix occasional panic on unload")
Cc: Tushar Dave <tushar.n.dave@intel.com>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>