Make sure we always excercise libbpf's ringbuf map size adjustment logic
by specifying non-zero size that's definitely not a page size multiple.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220509004148.1801791-10-andrii@kernel.org

Kernel imposes a pretty particular restriction on ringbuf map size. It
has to be a power-of-2 multiple of page size. While generally this isn't
hard for user to satisfy, sometimes it's impossible to do this
declaratively in BPF source code or just plain inconvenient to do at
runtime.

One such example might be BPF libraries that are supposed to work on
different architectures, which might not agree on what the common page
size is.

Let libbpf find the right size for user instead, if it turns out to not
satisfy kernel requirements. If user didn't set size at all, that's most
probably a mistake so don't upsize such zero size to one full page,
though. Also we need to be careful about not overflowing __u32
max_entries.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220509004148.1801791-9-andrii@kernel.org

Add barrier() and barrier_var() macros into bpf_helpers.h to be used by
end users. While a bit advanced and specialized instruments, they are
sometimes indispensable. Instead of requiring each user to figure out
exact asm volatile incantations for themselves, provide them from
bpf_helpers.h.

Also remove conflicting definitions from selftests. Some tests rely on
barrier_var() definition being nothing, those will still work as libbpf
does the #ifndef/#endif guarding for barrier() and barrier_var(),
allowing users to redefine them, if necessary.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220509004148.1801791-8-andrii@kernel.org

Add test cases for bpf_core_field_offset() helper.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220509004148.1801791-7-andrii@kernel.org

Add bpf_core_field_offset() helper to complete field-based CO-RE
helpers. This helper can be useful for feature-detection and for some
more advanced cases of field reading (e.g., reading flexible array members).
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220509004148.1801791-6-andrii@kernel.org

Excercise both supported forms of bpf_core_field_exists() and
bpf_core_field_size() helpers: variable-based field reference and
type/field name-based one.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220509004148.1801791-5-andrii@kernel.org

Allow to specify field reference in two ways:

  - if user has variable of necessary type, they can use variable-based
    reference (my_var.my_field or my_var_ptr->my_field). This was the
    only supported syntax up till now.
  - now, bpf_core_field_exists() and bpf_core_field_size() support also
    specifying field in a fashion similar to offsetof() macro, by
    specifying type of the containing struct/union separately and field
    name separately: bpf_core_field_exists(struct my_type, my_field).
    This forms is quite often more convenient in practice and it matches
    type-based CO-RE helpers that support specifying type by its name
    without requiring any variables.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220509004148.1801791-4-andrii@kernel.org

It will be annoying and surprising for users of __kptr and __kptr_ref if
libbpf silently ignores them just because Clang used for compilation
didn't support btf_type_tag(). It's much better to get clear compiler
error than debug BPF verifier failures later on.

Fixes: ef89654f ("libbpf: Add kptr type tag macros to bpf_helpers.h")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220509004148.1801791-3-andrii@kernel.org

Prevent "classic" and light skeleton generation rules from stomping on
each other's toes due to the use of the same <obj>.linked{1,2,3}.o
naming pattern. There is no coordination and synchronizataion between
.skel.h and .lskel.h rules, so they can easily overwrite each other's
intermediate object files, leading to errors like:

  /bin/sh: line 1: 170928 Bus error               (core dumped)
  /data/users/andriin/linux/tools/testing/selftests/bpf/tools/sbin/bpftool gen skeleton
  /data/users/andriin/linux/tools/testing/selftests/bpf/test_ksyms_weak.linked3.o
  name test_ksyms_weak
  > /data/users/andriin/linux/tools/testing/selftests/bpf/test_ksyms_weak.skel.h
  make: *** [Makefile:507: /data/users/andriin/linux/tools/testing/selftests/bpf/test_ksyms_weak.skel.h] Error 135
  make: *** Deleting file '/data/users/andriin/linux/tools/testing/selftests/bpf/test_ksyms_weak.skel.h'

Fix by using different suffix for light skeleton rule.

Fixes: c48e51c8 ("bpf: selftests: Add selftests for module kfunc support")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220509004148.1801791-2-andrii@kernel.org

Fix log_fp memory leak in dispatch_thread_read_log.
Remove obsolete log_fp clean-up code in dispatch_thread.

Also, release memory of subtest_selector. This can be
reproduced with -n 2/1 parameters.
Signed-off-by: Mykola Lysenko <mykolal@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220428225744.1961643-1-mykolal@fb.com

Andrii Nakryiko says:

====================

Add bpf_map__set_autocreate() API which is a BPF map counterpart of
bpf_program__set_autoload() and serves similar goal of allowing to build more
flexible CO-RE applications. See patch #3 for example scenarios in which the
need for such API came up previously.

Patch #1 is a follow-up patch to previous patch set adding verifier log fixup
logic, making sure bpf_core_format_spec()'s return result is used for
something useful.

Patch #2 is a small refactoring to avoid unnecessary verbose memory management
around obj->maps array.

Patch #3 adds and API and corresponding BPF verifier log fix up logic to
provide human-comprehensible error message with useful details.

Patch #4 adds a simple selftest validating both the API itself and libbpf's
log fixup logic for it.
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Add a subtest that excercises bpf_map__set_autocreate() API and
validates that libbpf properly fixes up BPF verifier log with correct
map information.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220428041523.4089853-5-andrii@kernel.org

Add bpf_map__set_autocreate() API that allows user to opt-out from
libbpf automatically creating BPF map during BPF object load.

This is a useful feature when building CO-RE-enabled BPF application
that takes advantage of some new-ish BPF map type (e.g., socket-local
storage) if kernel supports it, but otherwise uses some alternative way
(e.g., extra HASH map). In such case, being able to disable the creation
of a map that kernel doesn't support allows to successfully create and
load BPF object file with all its other maps and programs.

It's still up to user to make sure that no "live" code in any of their BPF
programs are referencing such map instance, which can be achieved by
guarding such code with CO-RE relocation check or by using .rodata
global variables.

If user fails to properly guard such code to turn it into "dead code",
libbpf will helpfully post-process BPF verifier log and will provide
more meaningful error and map name that needs to be guarded properly. As
such, instead of:

  ; value = bpf_map_lookup_elem(&missing_map, &zero);
  4: (85) call unknown#2001000000
  invalid func unknown#2001000000

... user will see:

  ; value = bpf_map_lookup_elem(&missing_map, &zero);
  4: <invalid BPF map reference>
  BPF map 'missing_map' is referenced but wasn't created
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220428041523.4089853-4-andrii@kernel.org

Reuse libbpf_mem_ensure() when adding a new map to the list of maps
inside bpf_object. It takes care of proper resizing and reallocating of
map array and zeroing out newly allocated memory.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220428041523.4089853-3-andrii@kernel.org

Detect CO-RE spec truncation and append "..." to make user aware that
there was supposed to be more of the spec there.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220428041523.4089853-2-andrii@kernel.org

Add new or modify existing SEC() definitions to be target-less and
validate that libbpf handles such program definitions correctly.

For kprobe/kretprobe we also add explicit test that generic
bpf_program__attach() works in cases when kprobe definition contains
proper target. It wasn't previously tested as selftests code always
explicitly specified the target regardless.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220428185349.3799599-4-andrii@kernel.org

Similar to previous patch, support target-less definitions like
SEC("fentry"), SEC("freplace"), etc. For such BTF-backed program types
it is expected that user will specify BTF target programmatically at
runtime using bpf_program__set_attach_target() *before* load phase. If
not, libbpf will report this as an error.

Aslo use SEC_ATTACH_BTF flag instead of explicitly listing a set of
types that are expected to require attach_btf_id. This was an accidental
omission during custom SEC() support refactoring.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220428185349.3799599-3-andrii@kernel.org

In a lot of cases the target of kprobe/kretprobe, tracepoint, raw
tracepoint, etc BPF program might not be known at the compilation time
and will be discovered at runtime. This was always a supported case by
libbpf, with APIs like bpf_program__attach_{kprobe,tracepoint,etc}()
accepting full target definition, regardless of what was defined in
SEC() definition in BPF source code.

Unfortunately, up till now libbpf still enforced users to specify at
least something for the fake target, e.g., SEC("kprobe/whatever"), which
is cumbersome and somewhat misleading.

This patch allows target-less SEC() definitions for basic tracing BPF
program types:

  - kprobe/kretprobe;
  - multi-kprobe/multi-kretprobe;
  - tracepoints;
  - raw tracepoints.

Such target-less SEC() definitions are meant to specify declaratively
proper BPF program type only. Attachment of them will have to be handled
programmatically using correct APIs. As such, skeleton's auto-attachment
of such BPF programs is skipped and generic bpf_program__attach() will
fail, if attempted, due to the lack of enough target information.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220428185349.3799599-2-andrii@kernel.org

The skb_to_sgvec fails only when the number of frag_list and frags
exceeds MAX_MSG_FRAGS. Therefore, we can call skb_linearize only
when the conversion fails.
Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220427115150.210213-1-liujian56@huawei.com

"respetively" should be "respectively".
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1651139754-4838-4-git-send-email-yangtiezhu@loongson.cn

According to include/uapi/linux/bpf.h:

  #define BPF_FROM_LE	BPF_TO_LE
  #define BPF_FROM_BE	BPF_TO_BE

BPF_FROM_BE exists as alias for BPF_TO_BE instead of BPF_TO_LE.
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1651139754-4838-3-git-send-email-yangtiezhu@loongson.cn

The word "instructions" is duplicated, remove it.
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1651139754-4838-2-git-send-email-yangtiezhu@loongson.cn

When xdp_rxq_info_user program exits unexpectedly, it doesn't detach xdp
prog of device, and other xdp prog can't be attached to the device. So
call init_exit() to detach xdp prog when program exits unexpectedly.
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220427062338.80173-1-shaozhengchao@huawei.com

Implement per subtest log collection for both parallel
and sequential test execution. This allows granular
per-subtest error output in the 'All error logs' section.
Add subtest log transfer into the protocol during the
parallel test execution.

Move all test log printing logic into dump_test_log
function. One exception is the output of test names when
verbose printing is enabled. Move test name/result
printing into separate functions to avoid repetition.

Print all successful subtest results in the log. Print
only failed test logs when test does not have subtests.
Or only failed subtests' logs when test has subtests.

Disable 'All error logs' output when verbose mode is
enabled. This functionality was already broken and is
causing confusion.
Signed-off-by: Mykola Lysenko <mykolal@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220427041353.246007-1-mykolal@fb.com

Daniel Borkmann says:

====================
pull-request: bpf-next 2022-04-27

We've added 85 non-merge commits during the last 18 day(s) which contain
a total of 163 files changed, 4499 insertions(+), 1521 deletions(-).

The main changes are:

1) Teach libbpf to enhance BPF verifier log with human-readable and relevant
   information about failed CO-RE relocations, from Andrii Nakryiko.

2) Add typed pointer support in BPF maps and enable it for unreferenced pointers
   (via probe read) and referenced ones that can be passed to in-kernel helpers,
   from Kumar Kartikeya Dwivedi.

3) Improve xsk to break NAPI loop when rx queue gets full to allow for forward
   progress to consume descriptors, from Maciej Fijalkowski & Björn Töpel.

4) Fix a small RCU read-side race in BPF_PROG_RUN routines which dereferenced
   the effective prog array before the rcu_read_lock, from Stanislav Fomichev.

5) Implement BPF atomic operations for RV64 JIT, and add libbpf parsing logic
   for USDT arguments under riscv{32,64}, from Pu Lehui.

6) Implement libbpf parsing of USDT arguments under aarch64, from Alan Maguire.

7) Enable bpftool build for musl and remove nftw with FTW_ACTIONRETVAL usage
   so it can be shipped under Alpine which is musl-based, from Dominique Martinet.

8) Clean up {sk,task,inode} local storage trace RCU handling as they do not
   need to use call_rcu_tasks_trace() barrier, from KP Singh.

9) Improve libbpf API documentation and fix error return handling of various
   API functions, from Grant Seltzer.

10) Enlarge offset check for bpf_skb_{load,store}_bytes() helpers given data
    length of frags + frag_list may surpass old offset limit, from Liu Jian.

11) Various improvements to prog_tests in area of logging, test execution
    and by-name subtest selection, from Mykola Lysenko.

12) Simplify map_btf_id generation for all map types by moving this process
    to build time with help of resolve_btfids infra, from Menglong Dong.

13) Fix a libbpf bug in probing when falling back to legacy bpf_probe_read*()
    helpers; the probing caused always to use old helpers, from Runqing Yang.

14) Add support for ARCompact and ARCv2 platforms for libbpf's PT_REGS
    tracing macros, from Vladimir Isaev.

15) Cleanup BPF selftests to remove old & unneeded rlimit code given kernel
    switched to memcg-based memory accouting a while ago, from Yafang Shao.

16) Refactor of BPF sysctl handlers to move them to BPF core, from Yan Zhu.

17) Fix BPF selftests in two occasions to work around regressions caused by latest
    LLVM to unblock CI until their fixes are worked out, from Yonghong Song.

18) Misc cleanups all over the place, from various others.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (85 commits)
  selftests/bpf: Add libbpf's log fixup logic selftests
  libbpf: Fix up verifier log for unguarded failed CO-RE relos
  libbpf: Simplify bpf_core_parse_spec() signature
  libbpf: Refactor CO-RE relo human description formatting routine
  libbpf: Record subprog-resolved CO-RE relocations unconditionally
  selftests/bpf: Add CO-RE relos and SEC("?...") to linked_funcs selftests
  libbpf: Avoid joining .BTF.ext data with BPF programs by section name
  libbpf: Fix logic for finding matching program for CO-RE relocation
  libbpf: Drop unhelpful "program too large" guess
  libbpf: Fix anonymous type check in CO-RE logic
  bpf: Compute map_btf_id during build time
  selftests/bpf: Add test for strict BTF type check
  selftests/bpf: Add verifier tests for kptr
  selftests/bpf: Add C tests for kptr
  libbpf: Add kptr type tag macros to bpf_helpers.h
  bpf: Make BTF type match stricter for release arguments
  bpf: Teach verifier about kptr_get kfunc helpers
  bpf: Wire up freeing of referenced kptr
  bpf: Populate pairs of btf_id and destructor kfunc in btf
  bpf: Adapt copy_map_value for multiple offset case
  ...
====================

Link: https://lore.kernel.org/r/20220427224758.20976-1-daniel@iogearbox.netSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The mib counters for the ksz9477 is same for the ksz9477 switch and
LAN937x switch. Hence moving it to ksz_common.c file in order to have it
generic function. The DSA hook get_stats64 now can call ksz_get_stats64.
Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20220426091048.9311-1-arun.ramadoss@microchip.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Jakub Kicinski says:

====================
net: remove non-Ethernet drivers using virt_to_bus()

Networking is currently the main offender in using virt_to_bus().
Frankly all the drivers which use it are super old and unlikely
to be used today. They are just an ongoing maintenance burden.

In other words this series is using virt_to_bus() as an excuse
to shed some old stuff. Having done the tree-wide dev_addr_set()
conversion recently I have limited sympathy for carrying dead
code.

Obviously please scream if any of these drivers _is_ in fact
still being used. Otherwise let's take the chance, we can always
apologize and revert if users show up later.

Also I should say thanks to everyone who contributed to this code!
The work continues to be appreciated although realistically in more
of a "history book" fashion...
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Another incarnation of Z8530, looks like? Again, no real changes
in the git history, and it needs VIRT_TO_BUS. Unlikely to have
users, let's spend less time refactoring dead code...
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Looks like all the changes to this driver had been automated
churn since git era begun. The driver is using virt_to_bus(),
it's just a maintenance burden unlikely to have any users.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Looks like all the changes to this driver had been automated
churn since git era begun. The driver is using virt_to_bus()
so it should be updated to a proper DMA API or removed. Given
the latest "news" entry on the website is from 1999 I'm opting
for the latter.

I'm marking the allocated char device major number as [REMOVED],
I reckon we can't reuse it in case some SW out there assumes its
COSA?
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

This driver received nothing but automated fixes in the last 15 years.
Since it's using virt_to_bus it's unlikely to be used on any modern
platform.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

This driver received nothing but automated fixes since git era begun.
Since it's using virt_to_bus it's unlikely to be used on any modern
platform.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

This driver received nothing but automated fixes (mostly spelling
and compiler warnings) since git era begun. Since it's using
virt_to_bus it's unlikely to be used on any modern platform.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Horatiu Vultur says:

====================
net: lan966x: Add support for PTP programmable pins

Lan966x has 8 PTP programmable pins. The last pin is hardcoded to be used
by PHC0 and all the rest are shareable between the PHCs. The PTP pins can
implement both extts and perout functions.

v1->v2:
- use ptp_find_pin_unlocked instead of ptp_find_pin inside the irq handler.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Extend the PTP programmable pins to implement also PTP_PF_EXTTS
function. The PTP pin can be configured to capture only on the rising
edge of the PPS signal. And once an event is seen then an interrupt is
generated and the local time counter is saved.
The interrupt is shared between all the pins.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Lan966x has 8 PTP programmable pins, where the last pins is hardcoded to
be used by PHC0, which does the frame timestamping. All the rest of the
PTP pins can be shared between the PHCs and can have different functions
like perout or extts. For now add support for PTP_FS_PEROUT.
The HW is not able to support absolute start time but can use the nsec
for phase adjustment when generating PPS.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add registers that are used to configure the PTP pins. These registers
are used to enable the interrupts per PTP pin and to set the waveform
generated by the pin.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

To read/write a value to a PHC, it is required to use a PTP pin.
Currently it is used pin 5, but change to pin 7 as is the last pin.
All the other pins will have different functions.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Extend dt-bindings for lan966x with ptp external interrupt. This is
generated when an external 1pps signal is received on the ptp pin.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Mat Martineau says:

====================
mptcp: Timeout for MP_FAIL response

When one peer sends an infinite mapping to coordinate fallback from
MPTCP to regular TCP, the other peer is expected to send a packet with
the MPTCP MP_FAIL option to acknowledge the infinite mapping. Rather
than leave the connection in some half-fallback state, this series adds
a timeout after which the infinite mapping sender will reset the
connection.

Patch 1 adds a fallback self test.

Patches 2-5 make use of the MPTCP socket's retransmit timer to reset the
MPTCP connection if no MP_FAIL was received.

Patches 6 and 7 extends the self test to check MP_FAIL-related MIBs.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>