Health buffer address is a 32 bit PCI address offset provided by
the FW. This offset is used for reading FW health debug data
located on the shared CR space. Cr space is accessible in both
driver and FW and allows for different queries and configurations.
Health buffer size is always 64B of readable data followed by a
lock which is used to block volatile CR space access.
Signed-off-by: Alex Vesker <valex@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add support for DEVLINK_CMD_REGION_READ_GET used for both reading
and dumping region data. Read allows reading from a region specific
address for given length. Dump allows reading the full region.
If only snapshot ID is provided a snapshot dump will be done.
If snapshot ID, Address and Length are provided a snapshot read
will done.

This is used for both snapshot access and will be used in the same
way to access current data on the region.
Signed-off-by: Alex Vesker <valex@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add support for DEVLINK_CMD_REGION_DEL used
for deleting a snapshot from a region. The snapshot ID is required.
Also added notification support for NEW and DEL of snapshots.
Signed-off-by: Alex Vesker <valex@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Extend the support for DEVLINK_CMD_REGION_GET command to also
return the IDs of the snapshot currently present on the region.
Each reply will include a nested snapshots attribute that
can contain multiple snapshot attributes each with an ID.
Signed-off-by: Alex Vesker <valex@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add support for DEVLINK_CMD_REGION_GET command which is used for
querying for the supported DEV/REGION values of devlink devices.
The support is both for doit and dumpit.

Reply includes:
  BUS_NAME, DEVICE_NAME, REGION_NAME, REGION_SIZE
Signed-off-by: Alex Vesker <valex@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Each device address region can store multiple snapshots,
each snapshot is identified using a different numerical ID.
This ID is used when deleting a snapshot or showing an address
region specific snapshot. This patch exposes a callback to add
a new snapshot to an address region.
The snapshot will be deleted using the destructor function
when destroying a region or when a snapshot delete command
from devlink user tool.
Signed-off-by: Alex Vesker <valex@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

To restrict the driver with the snapshot ID selection a new callback
is introduced for the driver to get the snapshot ID before creating
a new snapshot. This will also allow giving the same ID for multiple
snapshots taken of different regions on the same time.
Signed-off-by: Alex Vesker <valex@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This allows a device to register its supported address regions.
Each address region can be accessed directly for example reading
the snapshots taken of this address space.
Drivers are not limited in the name selection for different regions.
An example of a region-name can be: pci cr-space, register-space.
Signed-off-by: Alex Vesker <valex@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Maxime Chevallier says:

====================
net: mvpp2: add RSS support

This series adds support for RSS on PPv2. There already was some code to
handle the RSS tables, but the driver was missing all the classification
steps required to actually use these tables.

RSS is used through the classifier, using at least 2 lookups :
 - One using the C2 engine, a TCAM engine that match the packet based on
   some header extracted fields, assigns the default rx queue for that
   packet and tag it for RSS
 - One using the C3Hx engine, which computes the hash that's used to perform
   the lookup in the RSS table.

Since RSS spreads the load across CPUs, we need to make sure that packets
from the same flow are always assigned the same rx queue, to prevent
re-ordering.

This series therefore adds a classification step based on the Header Parser,
that separate ingress traffic into 52 flows, based on some L2, L3 and L4
parameters.

Patches 1 and 2 fix some header issues, from the driver splitting

Patches 3 to 7 make sure the correct receive queue setup is used for RSS

Patches 8 to 14 deal with the way we handle the RSS tables

Patch 15 implement basic classifier configuration, by using it to assign the
default receive queue

Patch 16 implement the ingress traffic splitting into multiple flows

Patch 17 adds RSS support, by using the needed classification steps

Patch 18 adds the required ethtool ops to configure the flow hash parameters

This was tested on MacchiatoBin, giving some nice performance improvements
using ip forwarding (going from 5Gbps to 9.6Gbps total throughput).

RSS is disabled by default.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This commit allows setting the RSS hash generation parameters from
ethtool. When setting parameters for a given flow type from ethtool
(e.g. tcp4), all the corresponding flows in the flow table are updated,
according to the supported hash parameters.

For example, when configuring TCP over IPv4 hash parameters to be
src/dst IP  + src/dst port ("ethtool -N eth0 rx-flow-hash tcp4 sdfn"),
we only set the "src/dst port" hash parameters on the non-fragmented TCP
over IPv4 flows.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

One of the classification action that can be performed is to compute a
hash of the packet header based on some header fields, and lookup a RSS
table based on this hash to determine the final RxQ.

This is done by adding one lookup entry per flow per port, so that we
can configure the hash generation parameters for each flow and each
port.

There are 2 possible engines that can be used for RSS hash generation :

 - C3HA, that generates a hash based on up to 4 header-extracted fields
 - C3HB, that does the same as c3HA, but also includes L4 info in the hash

There are a lot of fields that can be extracted from the header. For now,
we only use the ones that we can configure using ethtool :
 - DST MAC address
 - L3 info
 - Source IP
 - Destination IP
 - Source port
 - Destination port

The C3HB engine is selected when we use L4 fields (src/dst port).

               Header parser          Dec table
 Ingress pkt  +-------------+ flow id +----------------------------+
------------->| TCAM + SRAM |-------->|TCP IPv4 w/ VLAN, not frag  |
              +-------------+         |TCP IPv4 w/o VLAN, not frag |
                                      |TCP IPv4 w/ VLAN, frag      |--+
                                      |etc.                        |  |
                                      +----------------------------+  |
                                                                      |
                                            Flow table                |
  +---------+   +------------+         +--------------------------+   |
  | RSS tbl |<--| Classifier |<--------| flow 0: C2 lookup        |   |
  +---------+   +------------+         |         C3 lookup port 0 |   |
                 |         |           |         C3 lookup port 1 |   |
         +-----------+ +-------------+ |         ...              |   |
         | C2 engine | | C3H engines | | flow 1: C2 lookup        |<--+
         +-----------+ +-------------+ |         C3 lookup port 0 |
                                       |         ...              |
                                       | ...                      |
                                       | flow 51 : C2 lookup      |
                                       |           ...            |
                                       +--------------------------+

The C2 engine also gains the role of enabling and disabling the RSS
table lookup for this packet.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The PPv2 classifier allows to perform classification operations on each
ingress packet, based on the flow the packet is assigned to.

The current code uses only 1 flow per port, and the only classification
action consists of assigning the rx queue to the packet, depending on the
port.

In preparation for adding RSS support, we have to split all incoming
traffic into different flows. Since RSS assigns a rx queue depending on
the hash of some header fields, we have to make sure that the hash is
generated in a consistent way for all packets in the same flow.

What we call a "flow" is actually a set of attributes attached to a
packet that depends on various L2/L3/L4 info.

This patch introduces 52 flows, wich are a combination of various L2, L3
and L4 attributes :
 - Whether or not the packet has a VLAN tag
 - Whether the packet is IPv4, IPv6 or something else
 - Whether the packet is TCP, UDP or something else
 - Whether or not the packet is fragmented at L3 level.

The flow is associated to a packet by the Header Parser. Each flow
corresponds to an entry in the decoding table. This entry then points to
the sequence of classification lookups to be performed by the
classifier, represented in the flow table.

For now, the only lookup we perform is a C2 lookup to set the default
rx queue.

               Header parser          Dec table
 Ingress pkt  +-------------+ flow id +----------------------------+
------------->| TCAM + SRAM |-------->|TCP IPv4 w/ VLAN, not frag  |
              +-------------+         |TCP IPv4 w/o VLAN, not frag |
                                      |TCP IPv4 w/ VLAN, frag      |--+
                                      |etc.                        |  |
                                      +----------------------------+  |
                                                                      |
                                           Flow table                 |
                +------------+        +---------------------+         |
     To RxQ <---| Classifier |<-------| flow 0: C2 lookup   |<--------+
                +------------+        | flow 1: C2 lookup   |
                       |              | ...                 |
                +------------+        | flow 51 : C2 lookup |
		| C2 engine  |        +---------------------+
                +------------+
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The PPv2 Controller has a classifier, that can perform multiple lookup
operations for each packet, using different engines.

One of these engines is the C2 engine, which performs TCAM based lookups
on data extracted from the packet header. When a packet matches an
entry, the engine sets various attributes, used to perform
classification operations.

One of these attributes is the rx queue in which the packet should be sent.
The current code uses the lookup_id table (also called decoding table)
to assign the rx queue. However, this only works if we use one entry per
port in the decoding table, which won't be the case once we add RSS
lookups.

This patch uses the C2 engine to assign the rx queue to each packet.

The C2 engine is used through the flow table, which dictates what
classification operations are done for a given flow.

Right now, we have one flow per port, which contains every ingress
packet for this port.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mvpp22_init_rss function configures the RSS parameters for each port, so
rename it accordingly. Since this function relies on classifier
configuration, move its call right after the classifier config.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When filling the RSS table, we have to make sure that the rx queue is
attached to an online CPU.

This patch is not a full support for cpu_hotplug, but rather a way to
make sure that we don't break network on system booted with the maxcpus
parameter.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds an extra indirection when setting the indirection table
into the RSS hardware table to improve the packets distribution across
CPUs. For example, if 2 queues are used on a multi-core system this new
indirection will choose two queues on two different CPUs instead of the
two first queues which are on the same first CPU.
Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds the RSS indirection table support, allowing to use the
ethtool -x and -X options to dump and set this table.
Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
[Maxime: Small warning fixes, use one table per port]
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

PPv2 Controller has 8 RSS Tables, of 32 entries each. A lookup in the
RXQ2RSS_TABLE is performed for each incoming packet, and the RSS Table
to be used is chosen according to the default rx queue that would be
used for the packet.

This default rx queue is set in the Lookup_id Table (also called
Decoding Table), and is equal to the port->first_rxq.

Since the Classifier itself isn't active at any time for the moment,
this doesn't have a direct effect, the default rx queue at the moment is
the one where all packets end-up into.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

There is no RSS_TABLE register in PPv2 Controller. The register 0x1510
which was specified is actually named "RSS_HASH_SEL", but isn't used by
this driver at all.

Based on how this register was used, it should have been the
RXQ2RSS_TABLE register, which allows to select the RSS table that will
be used for the incoming packet.

The RSS_TABLE_POINTER is actually a field of this RXQ2RSS_TABLE
register.

Since RSS tables are actually not used by the driver for now, this
commit does not fix a runtime bug.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Cosmetic patch fixing a typo in one of the RSS comments.
Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The number of receive queue per port is :
 - MVPP2_DEFAULT_RXQ if in single queue mode
 - MVPP2_DEFAULT_RXQ * num_possible_cpus if in multi queue mode

with MVPP2_DEFAULT_RXQ = 4.

However, we don't use the extra rx queues at the moment, we really only
need one per port per CPU, until some more advanced classification rules
are implemented.
Suggested-by: Stefan Chulski <stefanc@marvell.com>
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

There's a dedicated #define that indicates the number of rx queues per
port per cpu, this commit removes a harcoded use of that value

This doesn't fix any runtime bugs since the harcoded value matches the
expected value.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Since RSS only applies when we have per-cpu rx queues, it should only
be enabled when the driver is configured to make use of multi-queue
mode.
Signed-off-by: Yan Markman <ymarkman@marvell.com>
[Maxime: Commit message]
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The multi queue mode is needed to have RSS available, and offers some
nice advantages, being able to have one rx queue vector per CPU.

This mode has been usable through the use of a module parameter, this
commit makes it the default value.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The PPv2 driver defines 2 "queue_modes" :
 - QDIST_SINGLE_MODE, where each port share one rx queue vector
   between all CPUs
 - QDIST_MULTI_MODE, where each port has one rx queue vector per CPU.

Multi queue mode isn't available on PPv2.1, make sure we fallback to
single mode when running on this revision.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The size of the the RSS indirection tables should be defined in mvpp2.h,
so that we can use it in all files of the PPv2 driver.

This commit moves the define in mvpp2.h, and adds the missing #include
in mvpp2_cls.h.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Include guards should be put before #includes. This doesn't fix any bug,
but prevent future compilation issues when adding new files in the mvpp2
driver

The Header Parser init function needs the platform_device definition,
and with the fixed include guards we need to add the missing include.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Following crash occurs in validate_xmit_skb_list() when same skb is
iterated multiple times in the loop and consume_skb() is called.

The root cause is calling list_del_init(&skb->list) and not clearing
skb->next in d4546c25. list_del_init(&skb->list) sets skb->next
to point to skb itself. skb->next needs to be cleared because other
parts of network stack uses another kind of SKB lists.
validate_xmit_skb_list() uses such list.

A similar type of bugfix was reported by Jesper Dangaard Brouer.
https://patchwork.ozlabs.org/patch/942541/

This patch clears skb->next and changes list_del_init() to list_del()
so that list->prev will maintain the list poison.

[  148.185511] ==================================================================
[  148.187865] BUG: KASAN: use-after-free in validate_xmit_skb_list+0x4b/0xa0
[  148.190158] Read of size 8 at addr ffff8801e52eefc0 by task swapper/1/0
[  148.192940]
[  148.193642] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.18.0-rc3+ #25
[  148.195423] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20180531_142017-buildhw-08.phx2.fedoraproject.org-1.fc28 04/01/2014
[  148.199129] Call Trace:
[  148.200565]  <IRQ>
[  148.201911]  dump_stack+0xc6/0x14c
[  148.203572]  ? dump_stack_print_info.cold.1+0x2f/0x2f
[  148.205083]  ? kmsg_dump_rewind_nolock+0x59/0x59
[  148.206307]  ? validate_xmit_skb+0x2c6/0x560
[  148.207432]  ? debug_show_held_locks+0x30/0x30
[  148.208571]  ? validate_xmit_skb_list+0x4b/0xa0
[  148.211144]  print_address_description+0x6c/0x23c
[  148.212601]  ? validate_xmit_skb_list+0x4b/0xa0
[  148.213782]  kasan_report.cold.6+0x241/0x2fd
[  148.214958]  validate_xmit_skb_list+0x4b/0xa0
[  148.216494]  sch_direct_xmit+0x1b0/0x680
[  148.217601]  ? dev_watchdog+0x4e0/0x4e0
[  148.218675]  ? do_raw_spin_trylock+0x10/0x120
[  148.219818]  ? do_raw_spin_lock+0xe0/0xe0
[  148.221032]  __dev_queue_xmit+0x1167/0x1810
[  148.222155]  ? sched_clock+0x5/0x10
[...]

[  148.474257] Allocated by task 0:
[  148.475363]  kasan_kmalloc+0xbf/0xe0
[  148.476503]  kmem_cache_alloc+0xb4/0x1b0
[  148.477654]  __build_skb+0x91/0x250
[  148.478677]  build_skb+0x67/0x180
[  148.479657]  e1000_clean_rx_irq+0x542/0x8a0
[  148.480757]  e1000_clean+0x652/0xd10
[  148.481772]  net_rx_action+0x4ea/0xc20
[  148.482808]  __do_softirq+0x1f9/0x574
[  148.483831]
[  148.484575] Freed by task 0:
[  148.485504]  __kasan_slab_free+0x12e/0x180
[  148.486589]  kmem_cache_free+0xb4/0x240
[  148.487634]  kfree_skbmem+0xed/0x150
[  148.488648]  consume_skb+0x146/0x250
[  148.489665]  validate_xmit_skb+0x2b7/0x560
[  148.490754]  validate_xmit_skb_list+0x70/0xa0
[  148.491897]  sch_direct_xmit+0x1b0/0x680
[  148.493949]  __dev_queue_xmit+0x1167/0x1810
[  148.495103]  br_dev_queue_push_xmit+0xce/0x250
[  148.496196]  br_forward_finish+0x276/0x280
[  148.497234]  __br_forward+0x44f/0x520
[  148.498260]  br_forward+0x19f/0x1b0
[  148.499264]  br_handle_frame_finish+0x65e/0x980
[  148.500398]  NF_HOOK.constprop.10+0x290/0x2a0
[  148.501522]  br_handle_frame+0x417/0x640
[  148.502582]  __netif_receive_skb_core+0xaac/0x18f0
[  148.503753]  __netif_receive_skb_one_core+0x98/0x120
[  148.504958]  netif_receive_skb_internal+0xe3/0x330
[  148.506154]  napi_gro_complete+0x190/0x2a0
[  148.507243]  dev_gro_receive+0x9f7/0x1100
[  148.508316]  napi_gro_receive+0xcb/0x260
[  148.509387]  e1000_clean_rx_irq+0x2fc/0x8a0
[  148.510501]  e1000_clean+0x652/0xd10
[  148.511523]  net_rx_action+0x4ea/0xc20
[  148.512566]  __do_softirq+0x1f9/0x574
[  148.513598]
[  148.514346] The buggy address belongs to the object at ffff8801e52eefc0
[  148.514346]  which belongs to the cache skbuff_head_cache of size 232
[  148.517047] The buggy address is located 0 bytes inside of
[  148.517047]  232-byte region [ffff8801e52eefc0, ffff8801e52ef0a8)
[  148.519549] The buggy address belongs to the page:
[  148.520726] page:ffffea000794bb00 count:1 mapcount:0 mapping:ffff880106f4dfc0 index:0xffff8801e52ee840 compound_mapcount: 0
[  148.524325] flags: 0x17ffffc0008100(slab|head)
[  148.525481] raw: 0017ffffc0008100 ffff880106b938d0 ffff880106b938d0 ffff880106f4dfc0
[  148.527503] raw: ffff8801e52ee840 0000000000190011 00000001ffffffff 0000000000000000
[  148.529547] page dumped because: kasan: bad access detected

Fixes: d4546c25 ("net: Convert GRO SKB handling to list_head.")
Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Reported-by: Tyler Hicks <tyhicks@canonical.com>
Tested-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Julian Wiedmann says:

====================
s390/qeth: updates 2018-07-11

please apply this first batch of qeth patches for net-next. It brings the
usual cleanups, and some performance improvements to the transmit paths.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Move the xmit of offload-eligible (ie IPv4) traffic on OSA over to the
new, copy-free path.
As with L2, we'll need to preserve the skb_orphan() behaviour of the
old code path until TX completion is sufficiently fast.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This implements a new xmit path for L3 HiperSockets, which carves the
HW header from skb headroom instead of allocating it from the hdr cache.
It also adds NETIF_F_SG support.

The delta in qeth_l3_xmit() is all just removal of IQD-specific code and
some minor consolidation.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In preparation for future work, move the high-level xmit work into a
separate wrapper. This matches the L2 xmit code.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When a L3 device doesn't offer TSO, allow the stack to build full-size
GSO skbs.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Remove some redundant EXPORTs. While at it, also move some L2-only
prototypes into the proper header file.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Reshuffle the code a bit so that everything is in one place.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Consolidate duplicated code, fix the misuse of RTN_UNSPEC and simplify
the handling of non-unicast traffic on IQD devices.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Changing a device's address lists (or its promisc mode) already triggers
an RX modeset, there's no need to do it manually from the L2 driver's
ndo_vlan_rx_kill_vid() hook.

Also when setting a device online, dev_open() already calls
dev_set_rx_mode(). So a manual modeset is only necessary from the
recovery path.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Except for tracing, the pointer is not used.

At the same time, accessing it from qeth_qdio_output_handler() is racy:
whenever qeth_qdio_cq_handler() gets control, its call to
qeth_qdio_handle_aob() frees the AOB.

So the AOB pointer that qeth_qdio_output_handler() stores into 'buffer'
can go stale at any time, and trigger a use-after-free.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use the new qeth_scrub_qdio_buffer() helper, remove an extra parameter
from qeth_clear_output_buffer(), init the bufstates.user field just once
(in qeth_flush_buffers()) and remove some noisy trace messages.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In commit 5fa12739 ("net: ipv4: listify ip_rcv_finish") calling
dst_input(skb) was split-out.  The ip_sublist_rcv_finish() just calls
dst_input(skb) in a loop.

The problem is that ip_sublist_rcv_finish() forgot to remove the SKB
from the list before invoking dst_input().  Further more we need to
clear skb->next as other parts of the network stack use another kind
of SKB lists for xmit_more (see dev_hard_start_xmit).

A crash occurs if e.g. dst_input() invoke ip_forward(), which calls
dst_output()/ip_output() that eventually calls __dev_queue_xmit() +
sch_direct_xmit(), and a crash occurs in validate_xmit_skb_list().

This patch only fixes the crash, but there is a huge potential for
a performance boost if we can pass an SKB-list through to ip_forward.

Fixes: 5fa12739 ("net: ipv4: listify ip_rcv_finish")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>