Pull KVM fixes from Paolo Bonzini:
 "The ARM changes are largish, but not too scary.  And a simple fix for
  x86 (bug introduced in 3.19)"

(Paolo sayus these are the "Final" fixes. We'll see).

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: check LAPIC presence when building apic_map
  arm/arm64: KVM: Use kernel mapping to perform invalidation on page fault
  arm/arm64: KVM: Invalidate data cache on unmap
  arm/arm64: KVM: Use set/way op trapping to track the state of the caches

Pull IOMMU fixes from Joerg Roedel:
 "Two small fixes for the Tegra GART IOMMU driver:

   - provide a .map_sg function for iommu_ops
   - do not register Tegra GART driver as a workaround because of issues
     with it when used from DRM code"

* tag 'iommu-fixes-v3.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/tegra: gart: Provide default ->map_sg() callback
  iommu/tegra: gart: Do not register with bus

Pull intel and dp mst drm fixes from Dave Airlie:
 "Intel had a few more fixes lined up and no point me sitting on them,
  along with a DP MST fix from Rob for a race at undock + vt switch"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm: fix fb-helper vs MST dangling connector ptrs (v2)
  drm/i915: BDW Fix Halo PCI IDs marked as ULT.
  drm/i915: Fix and clean BDW PCH identification
  drm/i915: Only fence tiled region of object.
  drm/i915: fix inconsistent brightness after resume
  drm/i915: Init PPGTT before context enable

Fix misspelled define.

Fixes: 33692f27 ("vm: add VM_FAULT_SIGSEGV handling support")
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We forgot to re-check LAPIC after splitting the loop in commit
173beedc (KVM: x86: Software disabled APIC should still deliver
NMIs, 2014-11-02).
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
Fixes: 173beedcSigned-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Merge tag 'kvm-arm-fixes-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master

Second round of fixes for KVM/ARM for 3.19.

Fixes memory corruption issues on APM platforms and swapping issues on
DMA-coherent systems.

misc i915 fixes, mostly all stable material as well.

* tag 'drm-intel-fixes-2015-01-29' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: BDW Fix Halo PCI IDs marked as ULT.
  drm/i915: Fix and clean BDW PCH identification
  drm/i915: Only fence tiled region of object.
  drm/i915: fix inconsistent brightness after resume
  drm/i915: Init PPGTT before context enable

VT switch back/forth from console to xserver (for example) has potential
to go horribly wrong if a dynamic DP MST connector ends up in the saved
modeset that is restored when switching back to fbcon.

When removing a dynamic connector, don't forget to clean up the saved
state.

v1: original
v2: null out set->fb if no more connectors to avoid making i915 cranky

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1184968
Cc: stable@vger.kernel.org #v3.17+
Signed-off-by: NRob Clark <robdclark@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Pull device mapper fixes from Mike Snitzer:
 "One stable fix for a dm-cache 3.19-rc6 regression and one stable fix
  for dm-thin:

   - fix DM cache metadata open/lookup error paths to properly use
     ERR_PTR and IS_ERR (fixes: 3.19-rc6 "stable" commit 9b1cc9f2)

   - fix DM thin-provisioning to disallow userspace from sending
     messages to the thin-pool if the pool is in READ_ONLY or FAIL mode
     since no metadata changes are allowed in these modes"

* tag 'dm-3.19-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm thin: don't allow messages to be sent to a pool target in READ_ONLY or FAIL mode
  dm cache: fix missing ERR_PTR returns and handling

Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

   - Stable fix for a NFSv4.1 Oops on mount
   - Stable fix for an O_DIRECT deadlock condition
   - Fix an issue with submounted volumes and fake duplicate inode
     numbers"

* tag 'nfs-for-3.19-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFS: Fix use of nfs_attr_use_mounted_on_fileid()
  NFSv4.1: Fix an Oops in nfs41_walk_client_list
  nfs: fix dio deadlock when O_DIRECT flag is flipped

Pull Ceph fixes from Sage Weil:
 "These paches from Ilya finally squash a race condition with layered
  images that he's been chasing for a while"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  rbd: drop parent_ref in rbd_dev_unprobe() unconditionally
  rbd: fix rbd_dev_parent_get() when parent_overlap == 0

When handling a fault in stage-2, we need to resync I$ and D$, just
to be sure we don't leave any old cache line behind.

That's very good, except that we do so using the *user* address.
Under heavy load (swapping like crazy), we may end up in a situation
where the page gets mapped in stage-2 while being unmapped from
userspace by another CPU.

At that point, the DC/IC instructions can generate a fault, which
we handle with kvm->mmu_lock held. The box quickly deadlocks, user
is unhappy.

Instead, perform this invalidation through the kernel mapping,
which is guaranteed to be present. The box is much happier, and so
am I.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

Let's assume a guest has created an uncached mapping, and written
to that page. Let's also assume that the host uses a cache-coherent
IO subsystem. Let's finally assume that the host is under memory
pressure and starts to swap things out.

Before this "uncached" page is evicted, we need to make sure
we invalidate potential speculated, clean cache lines that are
sitting there, or the IO subsystem is going to swap out the
cached view, loosing the data that has been written directly
into memory.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

Trying to emulate the behaviour of set/way cache ops is fairly
pointless, as there are too many ways we can end-up missing stuff.
Also, there is some system caches out there that simply ignore
set/way operations.

So instead of trying to implement them, let's convert it to VA ops,
and use them as a way to re-enable the trapping of VM ops. That way,
we can detect the point when the MMU/caches are turned off, and do
a full VM flush (which is what the guest was trying to do anyway).

This allows a 32bit zImage to boot on the APM thingy, and will
probably help bootloaders in general.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

Pull sound fixes from Takashi Iwai:
 "This batch ended up being larger than wished, but there is nothing to
  worry too much there.

  Most of commits are for ASoC, a compress NULL dereference fix, a fix
  for probe error handling, and the rest are device-specific fixes.  In
  addition, we have a fix for a long-standing but of seq-dummy driver,
  which just cuts off the buggy part in the end"

* tag 'sound-3.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: seq-dummy: remove deadlock-causing events on close
  ASoC: omap-mcbsp: Correct CBM_CFS dai format configuration
  ASoC: soc-compress.c: fix NULL dereference
  ASoC: rt286: set the same format for dac and adc
  ASoC: wm8904: fix runtime warning
  ASoC: simple-card: Fix crash in asoc_simple_card_unref()
  ASoC: fsl: imx-wm8962: Set the card owner field
  ASoC: pcm512x: Fix DSP program selection
  ASoC: rt5677: Modify the behavior that updates the PLL parameter.
  ASoC: fsl_ssi: Fix irq error check
  ASoC: rockchip: i2s: applys rate symmetry for CPU DAI
  ASoC: Intel: Add NULL checks for the stream pointer
  ASoC: wm8960: Fix capture sample rate from 11250 to 11025
  ASoC: adi: Add missing return statement.
  ASoC: Intel: Don't change offset of block allocator during fixed allocate
  ASoC: ts3a227e: Check and report jack status at probe
  ASoC: fsl_esai: Fix incorrect xDC field width of xCCR registers

Pull final pin control fix from Linus Walleij:
 "A late pin control fix for the v3.19 series: The AT91 gpio controller
  would miss wakeup events, this single fix make it work properly"

[ "Final"? Yeah, I'll believe that once I've actually released 3.19 ;)   - Linus ]

* tag 'pinctrl-v3.19-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: at91: allow to have disabled gpio bank

The stack guard page error case has long incorrectly caused a SIGBUS
rather than a SIGSEGV, but nobody actually noticed until commit
fee7e49d ("mm: propagate error from stack expansion even for guard
page") because that error case was never actually triggered in any
normal situations.

Now that we actually report the error, people noticed the wrong signal
that resulted.  So far, only the test suite of libsigsegv seems to have
actually cared, but there are real applications that use libsigsegv, so
let's not wait for any of those to break.
Reported-and-tested-by: NTakashi Iwai <tiwai@suse.de>
Tested-by: NJan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.

That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works.  However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.

In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV.  And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.

However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space.  And user space really
expected SIGSEGV, not SIGBUS.

To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it.  They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.

This is the mindless minimal patch to do this.  A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.

Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.
Reported-and-tested-by: NTakashi Iwai <tiwai@suse.de>
Tested-by: NJan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

You can't modify the metadata in these modes.  It's better to fail these
messages immediately than let the block-manager deny write locks on
metadata blocks.  Otherwise these failed metadata changes will trigger
'needs_check' to get set in the metadata superblock -- requiring repair
using the thin_check utility.
Signed-off-by: NJoe Thornber <ejt@redhat.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org

Commit 9b1cc9f2 ("dm cache: share cache-metadata object across
inactive and active DM tables") mistakenly ignored the use of ERR_PTR
returns.  Restore missing IS_ERR checks and ERR_PTR returns where
appropriate.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJoe Thornber <ejt@redhat.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org

This effectively reverts the last hunk of 392a9dad ("rbd: detect
when clone image is flattened").

The problem with parent_overlap != 0 condition is that it's possible
and completely valid to have an image with parent_overlap == 0 whose
parent state needs to be cleaned up on unmap.  The next commit, which
drops the "clone image now standalone" logic, opens up another window
of opportunity to hit this, but even without it

    # cat parent-ref.sh
    #!/bin/bash
    rbd create --image-format 2 --size 1 foo
    rbd snap create foo@snap
    rbd snap protect foo@snap
    rbd clone foo@snap bar
    rbd resize --allow-shrink --size 0 bar
    rbd resize --size 1 bar
    DEV=$(rbd map bar)
    rbd unmap $DEV

leaves rbd_device/rbd_spec/etc and rbd_client along with ceph_client
hanging around.

My thinking behind calling rbd_dev_parent_put() unconditionally is that
there shouldn't be any requests in flight at that point in time as we
are deep into unmap sequence.  Hence, even if rbd_dev_unparent() caused
by flatten is delayed by in-flight requests, it will have finished by
the time we reach rbd_dev_unprobe() caused by unmap, thus turning
unconditional rbd_dev_parent_put() into a no-op.

Fixes: http://tracker.ceph.com/issues/10352

Cc: stable@vger.kernel.org # 3.11+
Signed-off-by: NIlya Dryomov <idryomov@redhat.com>
Reviewed-by: NJosh Durgin <jdurgin@redhat.com>
Reviewed-by: NAlex Elder <elder@linaro.org>

The comment for rbd_dev_parent_get() said

    * We must get the reference before checking for the overlap to
    * coordinate properly with zeroing the parent overlap in
    * rbd_dev_v2_parent_info() when an image gets flattened.  We
    * drop it again if there is no overlap.

but the "drop it again if there is no overlap" part was missing from
the implementation.  This lead to absurd parent_ref values for images
with parent_overlap == 0, as parent_ref was incremented for each
img_request and virtually never decremented.

Fix this by leveraging the fact that refresh path calls
rbd_dev_v2_parent_info() under header_rwsem and use it for read in
rbd_dev_parent_get(), instead of messing around with atomics.  Get rid
of barriers in rbd_dev_v2_parent_info() while at it - I don't see what
they'd pair with now and I suspect we are in a pretty miserable
situation as far as proper locking goes regardless.

Cc: stable@vger.kernel.org # 3.11+
Signed-off-by: NIlya Dryomov <idryomov@redhat.com>
Reviewed-by: NJosh Durgin <jdurgin@redhat.com>
Reviewed-by: NAlex Elder <elder@linaro.org>

Pull drm fixes from Dave Airlie:
 "This feels larger than I'd like but its for three reasons.

   a) amdkfd finalising the API more, this is a new feature introduced
      last merge window, and I'd prefer to make the tweaks to the API
      before it first gets into a stable release.

   b) radeon regression required splitting an internal API to fix
      properly, so it just changed a few more lines

   c) vmwgfx fix changes a lock from a mutex->spin lock, this is fallout
      from the new sleep checking.

  Otherwise there is just some tda998x fixes"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/radeon: Remove rdev->gart.pages_addr array
  drm/radeon: Restore GART table contents after pinning it in VRAM v3
  drm/radeon: Split off gart_get_page_entry ASIC hook from set_page_entry
  drm/amdkfd: Fix bug in call to init_pipelines()
  drm/amdkfd: Fix bug in pipelines initialization
  drm/radeon: Don't increment pipe_id in kgd_init_pipeline
  drm/i2c: tda998x: set the CEC I2C address based on the slave I2C address
  drm/vmwgfx: Replace the hw mutex with a hw spinlock
  drm/amdkfd: Allow user to limit only queues per device
  drm/amdkfd: PQM handle queue creation fault
  drm: tda998x: Fix EDID read timeout on HDMI connect
  drm: tda998x: Protect the page register

Pull networking fixes from David Miller:

 1) Don't OOPS on socket AIO, from Christoph Hellwig.

 2) Scheduled scans should be aborted upon RFKILL, from Emmanuel
    Grumbach.

 3) Fix sleep in atomic context in kvaser_usb, from Ahmed S Darwish.

 4) Fix RCU locking across copy_to_user() in bpf code, from Alexei
    Starovoitov.

 5) Lots of crash, memory leak, short TX packet et al bug fixes in
    sh_eth from Ben Hutchings.

 6) Fix memory corruption in SCTP wrt.  INIT collitions, from Daniel
    Borkmann.

 7) Fix return value logic for poll handlers in netxen, enic, and bnx2x.
    From Eric Dumazet and Govindarajulu Varadarajan.

 8) Header length calculation fix in mac80211 from Fred Chou.

 9) mv643xx_eth doesn't handle highmem correctly in non-TSO code paths.
    From Ezequiel Garcia.

10) udp_diag has bogus logic in it's hash chain skipping, copy same fix
    tcp diag used.  From Herbert Xu.

11) amd-xgbe programs wrong rx flow control register, from Thomas
    Lendacky.

12) Fix race leading to use after free in ping receive path, from Subash
    Abhinov Kasiviswanathan.

13) Cache redirect routes otherwise we can get a heavy backlog of rcu
    jobs liberating DST_NOCACHE entries.  From Hannes Frederic Sowa.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (48 commits)
  net: don't OOPS on socket aio
  stmmac: prevent probe drivers to crash kernel
  bnx2x: fix napi poll return value for repoll
  ipv6: replacing a rt6_info needs to purge possible propagated rt6_infos too
  sh_eth: Fix DMA-API usage for RX buffers
  sh_eth: Check for DMA mapping errors on transmit
  sh_eth: Ensure DMA engines are stopped before freeing buffers
  sh_eth: Remove RX overflow log messages
  ping: Fix race in free in receive path
  udp_diag: Fix socket skipping within chain
  can: kvaser_usb: Fix state handling upon BUS_ERROR events
  can: kvaser_usb: Retry the first bulk transfer on -ETIMEDOUT
  can: kvaser_usb: Send correct context to URB completion
  can: kvaser_usb: Do not sleep in atomic context
  ipv4: try to cache dst_entries which would cause a redirect
  samples: bpf: relax test_maps check
  bpf: rcu lock must not be held when calling copy_to_user()
  net: sctp: fix slab corruption from use after free on INIT collisions
  net: mv643xx_eth: Fix highmem support in non-TSO egress path
  sh_eth: Fix serialisation of interrupt disable with interrupt & NAPI handlers
  ...

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the case when alloc_netdev fails we return NULL to a caller. But there is no
check for NULL in the probe drivers. This patch changes NULL to an error
pointer. The function description is amended to reflect what we may get
returned.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull powerpc fixes from Michael Ellerman:
 "Two powerpc fixes"

* tag 'powerpc-3.19-5' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux:
  powerpc/powernv: Restore LPCR with LPCR_PECE1 cleared
  powerpc/xmon: Fix another endiannes issue in RTAS call from xmon

Pull one more module fix from Rusty Russell:
 "SCSI was using module_refcount() to figure out when the module was
  unloading: this broke with new atomic refcounting.  The code is still
  suspicious, but this solves the WARN_ON()"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  scsi: always increment reference count

With the commit d75b1ade ("net: less interrupt masking in NAPI") napi
repoll is done only when work_done == budget. When in busy_poll is we return 0
in napi_poll. We should return budget.
Signed-off-by: NGovindarajulu Varadarajan <_govind@gmx.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Steffen Klassert says:

====================
ipsec 2015-01-26

Just two small fixes for _decode_session6() where we
might decode to wrong header information in some rare
situations.

Please pull or let me know if there are problems.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Lubomir Rintel reported that during replacing a route the interface
reference counter isn't correctly decremented.

To quote bug <https://bugzilla.kernel.org/show_bug.cgi?id=91941>:
| [root@rhel7-5 lkundrak]# sh -x lal
| + ip link add dev0 type dummy
| + ip link set dev0 up
| + ip link add dev1 type dummy
| + ip link set dev1 up
| + ip addr add 2001:db8:8086::2/64 dev dev0
| + ip route add 2001:db8:8086::/48 dev dev0 proto static metric 20
| + ip route add 2001:db8:8088::/48 dev dev1 proto static metric 10
| + ip route replace 2001:db8:8086::/48 dev dev1 proto static metric 20
| + ip link del dev0 type dummy
| Message from syslogd@rhel7-5 at Jan 23 10:54:41 ...
|  kernel:unregister_netdevice: waiting for dev0 to become free. Usage count = 2
|
| Message from syslogd@rhel7-5 at Jan 23 10:54:51 ...
|  kernel:unregister_netdevice: waiting for dev0 to become free. Usage count = 2

During replacement of a rt6_info we must walk all parent nodes and check
if the to be replaced rt6_info got propagated. If so, replace it with
an alive one.

Fixes: 4a287eba ("IPv6 routing, NLM_F_* flag support: REPLACE and EXCL flags support, warn about missing CREATE flag")
Reported-by: NLubomir Rintel <lkundrak@v3.sk>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Tested-by: NLubomir Rintel <lkundrak@v3.sk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ben Hutchings says:

====================
Fixes for sh_eth #3

I'm continuing review and testing of Ethernet support on the R-Car H2
chip.  This series fixes the last of the more serious issues I've found.

These are not tested on any of the other supported chips.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

- Use the return value of dma_map_single(), rather than calling
  virt_to_page() separately
- Check for mapping failue
- Call dma_unmap_single() rather than dma_sync_single_for_cpu()
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

dma_map_single() may fail if an IOMMU or swiotlb is in use, so
we need to check for this.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently we try to clear EDRRR and EDTRR and immediately continue to
free buffers.  This is unsafe because:

- In general, register writes are not serialised with DMA, so we still
  have to wait for DMA to complete somehow
- The R8A7790 (R-Car H2) manual states that the TX running flag cannot
  be cleared by writing to EDTRR
- The same manual states that clearing the RX running flag only stops
  RX DMA at the next packet boundary

I applied this patch to the driver to detect DMA writes to freed
buffers:

> --- a/drivers/net/ethernet/renesas/sh_eth.c
> +++ b/drivers/net/ethernet/renesas/sh_eth.c
> @@ -1098,7 +1098,14 @@ static void sh_eth_ring_free(struct net_device *ndev)
>  	/* Free Rx skb ringbuffer */
>  	if (mdp->rx_skbuff) {
>  		for (i = 0; i < mdp->num_rx_ring; i++)
> +			memcpy(mdp->rx_skbuff[i]->data,
> +			       "Hello, world", 12);
> +		msleep(100);
> +		for (i = 0; i < mdp->num_rx_ring; i++) {
> +			WARN_ON(memcmp(mdp->rx_skbuff[i]->data,
> +				       "Hello, world", 12));
>  			dev_kfree_skb(mdp->rx_skbuff[i]);
> +		}
>  	}
>  	kfree(mdp->rx_skbuff);
>  	mdp->rx_skbuff = NULL;

then ran the loop:

    while ethtool -G eth0 rx 128 ; ethtool -G eth0 rx 64; do echo -n .; done

and 'ping -f' toward the sh_eth port from another machine.  The
warning fired several times a minute.

To fix these issues:

- Deactivate all TX descriptors rather than writing to EDTRR
- As there seems to be no way of telling when RX DMA is stopped,
  perform a soft reset to ensure that both DMA enginess are stopped
- To reduce the possibility of the reset truncating a transmitted
  frame, disable egress and wait a reasonable time to reach a
  packet boundary before resetting
- Update statistics before resetting

(The 'reasonable time' does not allow for CS/CD in half-duplex
mode, but half-duplex no longer seems reasonable!)
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If RX traffic is overflowing the FIFO or DMA ring, logging every time
this happens just makes things worse.  These errors are visible in the
statistics anyway.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Merge tag 'linux-can-fixes-for-3.19-20150127' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can

Marc Kleine-Budde says:

====================
pull-request: can 2015-01-27

this is another pull request for net/master which consists of 4 patches.

All 4 patches are contributed by Ahmed S. Darwish, he fixes more problems in
the kvaser_usb driver.

David, please merge net/master to net-next/master, as we have more kvaser_usb
patches in the queue, that target net-next.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

An exception is seen in ICMP ping receive path where the skb
destructor sock_rfree() tries to access a freed socket. This happens
because ping_rcv() releases socket reference with sock_put() and this
internally frees up the socket. Later icmp_rcv() will try to free the
skb and as part of this, skb destructor is called and which leads
to a kernel panic as the socket is freed already in ping_rcv().

-->|exception
-007|sk_mem_uncharge
-007|sock_rfree
-008|skb_release_head_state
-009|skb_release_all
-009|__kfree_skb
-010|kfree_skb
-011|icmp_rcv
-012|ip_local_deliver_finish

Fix this incorrect free by cloning this skb and processing this cloned
skb instead.

This patch was suggested by Eric Dumazet
Signed-off-by: NSubash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While working on rhashtable walking I noticed that the UDP diag
dumping code is buggy.  In particular, the socket skipping within
a chain never happens, even though we record the number of sockets
that should be skipped.

As this code was supposedly copied from TCP, this patch does what
TCP does and resets num before we walk a chain.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While being in an ERROR_WARNING state, and receiving further
bus error events with error counters still in the ERROR_WARNING
range of 97-127 inclusive, the state handling code erroneously
reverts back to ERROR_ACTIVE.

Per the CAN standard, only revert to ERROR_ACTIVE when the
error counters are less than 96.

Moreover, in certain Kvaser models, the BUS_ERROR flag is
always set along with undefined bits in the M16C status
register. Thus use bitwise operators instead of full equality
for checking that register against bus errors.
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>