tcp_fastopen.c hasn't use any macro or function declared in crypto.h, err.h,
init.h, list.h, rculist.h and inetpeer.h. Thus, these files can be removed
from tcp_fastopen.c safely without affecting the compilation of the net module.
Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>

route.c hasn't use any macro or function declared in uaccess.h, types.h,
string.h, sockios.h, times.h, protocol.h, arp.h and l3mdev.h. Thus, these
files can be removed from route.c safely without affecting the compilation
of the net module.
Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add support for jumbo frames. Full support for jumbo frames requires
changes in the DSA switch driver (lantiq_gswip.c).

Tested on BT Hone Hub 5A.
Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>

M Chetan Kumar says:

====================
net: wwan: iosm: fw flashing & cd collection

This patch series brings-in support for M.2 7560 Device firmware flashing &
coredump collection using devlink.
- Driver Registers with Devlink framework.
- Register devlink params callback for configuring device params
  required in flashing or coredump flow.
- Implements devlink ops flash_update callback that programs modem
  firmware.
- Creates region & snapshot required for device coredump log collection.

On early detection of device in boot rom stage. Driver registers with
Devlink framework and establish transport channel for PSI (Primary Signed
Image) injection. Once PSI is injected to device, the device execution
stage details are read to determine whether device is in flash or
exception mode. The collected information is reported to devlink user
space application & based on this informationi, application proceeds with
either modem firmware flashing or coredump collection.

Refer to iosm devlink documentation for details on Devlink Params, flash
update and coredump collection command usage.

Note: Patches are interdependent. Need to apply complete patch series for
compilation.

Changes since v1:
  * Break down single patch into multiple patches.
  * IOSM Driver devlink documentation.
  * Fixes NULL parameter deference in ipc_devlink_flash_update() reported
    by smatch static checker.
  * Fixes memory leak in ipc_devlink_create_region().
  * Use kmemdup instead of kzalloc and memcpy in ipc_flash_boot_psi().
  * Fixes linux-net build error.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

IOSM Makefile & WWAN Kconfig changes to support fw flashing & cd
collection module compliation.
Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documents devlink params, fw update & cd collection commands
and its usage.
Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Implements transport layer protocol for fw flashing/coredump
collection.
Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Implements protocol for coredump collection.
Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Implements protocol for fw flashing and PSI injection for
coredump collection.
Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Register with devlink framework and implment callbacks required
for fw flashing and coredump collection.
Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix spacing and improve name for 83xx phy following other phy in the
same driver.
Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add resume/suspend function to qca83xx internal phy.
We can't use the at803x generic function as the documentation lacks of
any support for WoL regs.
Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

For qca8327 internal phy there are 2 different switch variant with 2
different phy id. Add this missing variant so the internal phy can be
correctly identified and fixed.
Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

This implements ndo_tx_timeout handler and put this into stats. When
there is something wrong to send out packets, we could notice tx timeout
events and total timeout counter.

We have suffered send timeout issues due to the backends hung. With this,
we can find the details, and collect the counters by monitor systems.
Signed-off-by: Tony Lu <tony.ly@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

As per HW errata AQ modification to CQ could be discarded on heavy
traffic. This patch implements workaround for the same after each
CQ write by AQ check whether the requested fields (except those
which HW can update eg: avg_level) are properly updated or not.

If CQ context is not updated then perform AQ write again.
Signed-off-by: Hariprasad Kelam <hkelam@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The code for handling active queue changes is identical
between mq and mqprio, reuse it.
Suggested-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Dan Carpenter points out that we have a code path that permits a NULL
netdev pointer to be passed to netif_carrier_off(), which will cause
a kernel oops. In any case, we need to set pl->old_link_state to false
to have the desired effect when there is no netdev present.

Fixes: f9749365 ("net: phylink: add suspend/resume support")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

It no need barrier when assigning a NULL value to an RCU protected
pointer. So use RCU_INIT_POINTER() instead for more fast.
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>

This warning is output when virtnet does not have enough queues, but it
only needs to be printed once to inform the user of this situation. It
is not necessary to print it every time. If the user loads xdp
frequently, this log appears too much.
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

this patch fixes below Errors reported by checkpatch
    ERROR: do not initialise globals to 0
    +int cipso_v4_rbm_optfmt = 0;
Signed-off-by: wangzhitong <wangzhitong@uniontech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The key_domain member in struct net only exists if we define CONFIG_KEYS.
So we should add the define when we used key_domain.

Fixes: 9b242610 ("keys: Network namespace domain tag")
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>

Phylink documentation says:
  Note that the PHY may be able to transform from one connection
  technology to another, so, eg, don't clear 1000BaseX just
  because the MAC is unable to BaseX mode. This is more about
  clearing unsupported speeds and duplex settings. The port modes
  should not be cleared; phylink_set_port_modes() will help with this.

So add the missing 10G modes.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Marek Behún <kabel@kernel.org>
Acked-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Mat Martineau says:

====================
mptcp: Add SOL_MPTCP getsockopt support

Here's the first new MPTCP feature for the v5.16 cycle, and I'll defer
to Florian's helpful description of the series implementing some new
MPTCP socket options:

========

This adds the MPTCP_INFO, MPTCP_TCPINFO and MPTCP_SUBFLOW_ADDRS
mptcp getsockopt optnames.

MPTCP_INFO exposes the mptcp_info struct as an alternative to the
existing netlink diag interface.

MPTCP_TCPINFO exposes the tcp_info struct.
Unlike SOL_TCP/TCP_INFO, this returns one struct for each active
subflow.

MPTCP_SUBFLOW_ADDRS allows userspace to discover the ip addresses/ports
used by the local and remote endpoints, one for each active tcp subflow.

MPTCP_TCPINFO and MPTCP_SUBFLOW_ADDRS share the same meta-header that
needs to be pre-filled by userspace with the size of the data structures
it expects.  This is done to allow extension of the involved structs
later on, without breaking backwards compatibility.

The meta-structure can also be used to discover the required space
to obtain all information, as kernel will fill in the number of
active subflows even if there is not enough room for the requested info
itself.

More information is available in the individual patches.
Last patch adds test cases for the three optnames.

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

Add a test program that retrieves the three info types:
1. mptcp meta information
2. tcp info for subflow
3. subflow endpoint addresses

For all three rudimentary checks are added.

1. Meta information checks that the logical mptcp
   sequence numbers advance as expected, based on the bytes read
   (init seq + bytes_received/sent) and the connection state
   (after close, we should exect 1 extra byte due to FIN).

2. TCP info checks the number of bytes sent/received vs.
   sums of read/write syscall return values.

3. Subflow endpoint addresses are checked vs. getsockname/getpeername
   result.

Tests for forward compatibility (0-initialisation of output-only
fields in mptcp_subflow_data structure) are added as well.
Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This retrieves the address pairs of all subflows currently
active for a given mptcp connection.

It re-uses the same meta-header as for MPTCP_TCPINFO.

A new structure is provided to hold the subflow
address data:

struct mptcp_subflow_addrs {
	union {
		__kernel_sa_family_t sa_family;
		struct sockaddr sa_local;
		struct sockaddr_in sin_local;
		struct sockaddr_in6 sin6_local;
		struct sockaddr_storage ss_local;
	};
	union {
		struct sockaddr sa_remote;
		struct sockaddr_in sin_remote;
		struct sockaddr_in6 sin6_remote;
		struct sockaddr_storage ss_remote;
	};
};

Usage of the new getsockopt is very similar to
MPTCP_TCPINFO one.

Userspace allocates a
'struct mptcp_subflow_data', followed by one or
more 'struct mptcp_subflow_addrs', then inits the
mptcp_subflow_data structure as follows:

struct mptcp_subflow_addrs *sf_addr;
struct mptcp_subflow_data *addr;
socklen_t olen = sizeof(*addr) + (8 * sizeof(*sf_addr));

addr = malloc(olen);
addr->size_subflow_data = sizeof(*addr);
addr->num_subflows = 0;
addr->size_kernel = 0;
addr->size_user = sizeof(struct mptcp_subflow_addrs);

sf_addr = (struct mptcp_subflow_addrs *)(addr + 1);

and then retrieves the endpoint addresses via:
ret = getsockopt(fd, SOL_MPTCP, MPTCP_SUBFLOW_ADDRS,
		 addr, &olen);

If the call succeeds, kernel will have added up to 8
endpoint addresses after the 'mptcp_subflow_data' header.

Userspace needs to re-check 'olen' value to detect how
many bytes have been filled in by the kernel.

Userspace can check addr->num_subflows to discover when
there were more subflows that available data space.
Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Allow users to retrieve TCP_INFO data of all subflows.

Users need to pre-initialize a meta header that has to be
prepended to the data buffer that will be filled with the tcp info data.

The meta header looks like this:

struct mptcp_subflow_data {
 __u32 size_subflow_data;/* size of this structure in userspace */
 __u32 num_subflows;	/* must be 0, set by kernel */
 __u32 size_kernel;	/* must be 0, set by kernel */
 __u32 size_user;	/* size of one element in data[] */
} __attribute__((aligned(8)));

size_subflow_data has to be set to 'sizeof(struct mptcp_subflow_data)'.
This allows to extend mptcp_subflow_data structure later on without
breaking backwards compatibility.

If the structure is extended later on, kernel knows where the
userspace-provided meta header ends, even if userspace uses an older
(smaller) version of the structure.

num_subflows must be set to 0. If the getsockopt request succeeds (return
value is 0), it will be updated to contain the number of active subflows
for the given logical connection.

size_kernel must be set to 0. If the getsockopt request is successful,
it will contain the size of the 'struct tcp_info' as known by the kernel.
This is informational only.

size_user must be set to 'sizeof(struct tcp_info)'.

This allows the kernel to only fill in the space reserved/expected by
userspace.

Example:

struct my_tcp_info {
  struct mptcp_subflow_data d;
  struct tcp_info ti[2];
};
struct my_tcp_info ti;
socklen_t olen;

memset(&ti, 0, sizeof(ti));

ti.d.size_subflow_data = sizeof(struct mptcp_subflow_data);
ti.d.size_user = sizeof(struct tcp_info);
olen = sizeof(ti);

ret = getsockopt(fd, SOL_MPTCP, MPTCP_TCPINFO, &ti, &olen);
if (ret < 0)
	die_perror("getsockopt MPTCP_TCPINFO");

mptcp_subflow_data.num_subflows is populated with the number of
subflows that exist on the kernel side for the logical mptcp connection.

This allows userspace to re-try with a larger tcp_info array if the number
of subflows was larger than the available space in the ti[] array.

olen has to be set to the number of bytes that userspace has allocated to
receive the kernel data.  It will be updated to contain the real number
bytes that have been copied to by the kernel.

In the above example, if the number if subflows was 1, olen is equal to
'sizeof(struct mptcp_subflow_data) + sizeof(struct tcp_info).
For 2 or more subflows olen is equal to 'sizeof(struct my_tcp_info)'.

If there was more data that could not be copied due to lack of space
in the option buffer, userspace can detect this by checking
mptcp_subflow_data->num_subflows.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Its not compatible with multipath-tcp.org kernel one.

1. The out-of-tree implementation defines a different 'struct mptcp_info',
   with embedded __user addresses for additional data such as
   endpoint addresses.

2. Mat Martineau points out that embedded __user addresses doesn't work
with BPF_CGROUP_RUN_PROG_GETSOCKOPT() which assumes that copying in
optsize bytes from optval provides all data that got copied to userspace.

This provides mptcp_info data for the given mptcp socket.

Userspace sets optlen to the size of the structure it expects.
The kernel updates it to contain the number of bytes that it copied.

This allows to append more information to the structure later.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Will be re-used from getsockopt path.
Since diag can be a module, we can't export the helper from diag, it
needs to be moved to core.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Claudiu Beznea says:

====================
net: macb: add support for MII on RGMII interface

This series adds support for MII mode on RGMII interface (patches 3/4,
4/4). Along with this the series also contains minor cleanups (patches 1/3,
2/3) on macb.h.

Changes in v2:
- added patch 4/4 to enable MII on RGMII support for SAMA7G5 MAC IPs
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Both MAC IPs available on SAMA7G5 support MII on RGMII feature.
Enable these by adding proper capability to proper macb_config
objects.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Cadence IP has option to enable MII support on RGMII interface. This
could be selected though bit 28 of network control register. This option
is not enabled on all the IP versions thus add a software capability to
be selected by the proper implementation of this IP.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Align for OSSMODE offset.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add description for SRTSM bit.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When we are using a dedicated PHY driver (not the Generic PHY driver)
chances are that it is going to configure RGMII delays and do that in a
way that is incompatible with our incorrect interpretation of the
phy_interface value.

Add a quirk in order to reverse the PHY_INTERFACE_MODE_RGMII to the
value of PHY_INTERFACE_MODE_RGMII_ID such that the MAC continues to be
configured the way it used to be, but the PHY driver can account for
adding delays. Conversely when PHY_INTERFACE_MODE_RGMII_TXID is
specified, return PHY_INTERFACE_MODE_RGMII_RXID to the PHY since we will
have enabled a TXC MAC delay (id_mode_dis=0, meaning there is a delay
inserted).

This is not considered a bug fix at this point since it only affects
Broadcom STB platforms shipping with a Device Tree blob that is not
updatable in the field (quite a few devices out there) and which was
generated using the scripted Device Tree environment shipped with those
platforms' SDK.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Sky2 is parsing the VPD and adds the parsed information to its debugfs
file. This isn't needed in kernel, userspace tools like lspci can be
used to display such information nicely. Therefore remove this from
the driver.

lspci -vv:

Capabilities: [50] Vital Product Data
	Product Name: Marvell Yukon 88E8070 Gigabit Ethernet Controller
	Read-only fields:
		[PN] Part number: Yukon 88E8070
		[EC] Engineering changes: Rev. 1.0
		[MN] Manufacture ID: Marvell
		[SN] Serial number: AbCdEfG970FD4
		[CP] Extended capability: 01 10 cc 03
		[RV] Reserved: checksum good, 9 byte(s) reserved
	Read/write fields:
		[RW] Read-write area: 1 byte(s) free
	End

Relevant part in debugfs file:

0000:01:00.0 Product Data
Marvell Yukon 88E8070 Gigabit Ethernet Controller
 Part Number: Yukon 88E8070
 Engineering Level: Rev. 1.0
 Manufacturer: Marvell
 Serial Number: AbCdEfG970FD4
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Link: https://lore.kernel.org/r/bbaee8ab-9b2e-de04-ee7b-571e094cc5fe@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Alexei Starovoitov says:

====================
pull-request: bpf-next 2021-09-17

We've added 63 non-merge commits during the last 12 day(s) which contain
a total of 65 files changed, 2653 insertions(+), 751 deletions(-).

The main changes are:

1) Streamline internal BPF program sections handling and
   bpf_program__set_attach_target() in libbpf, from Andrii.

2) Add support for new btf kind BTF_KIND_TAG, from Yonghong.

3) Introduce bpf_get_branch_snapshot() to capture LBR, from Song.

4) IMUL optimization for x86-64 JIT, from Jie.

5) xsk selftest improvements, from Magnus.

6) Introduce legacy kprobe events support in libbpf, from Rafael.

7) Access hw timestamp through BPF's __sk_buff, from Vadim.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (63 commits)
  selftests/bpf: Fix a few compiler warnings
  libbpf: Constify all high-level program attach APIs
  libbpf: Schedule open_opts.attach_prog_fd deprecation since v0.7
  selftests/bpf: Switch fexit_bpf2bpf selftest to set_attach_target() API
  libbpf: Allow skipping attach_func_name in bpf_program__set_attach_target()
  libbpf: Deprecated bpf_object_open_opts.relaxed_core_relocs
  selftests/bpf: Stop using relaxed_core_relocs which has no effect
  libbpf: Use pre-setup sec_def in libbpf_find_attach_btf_id()
  bpf: Update bpf_get_smp_processor_id() documentation
  libbpf: Add sphinx code documentation comments
  selftests/bpf: Skip btf_tag test if btf_tag attribute not supported
  docs/bpf: Add documentation for BTF_KIND_TAG
  selftests/bpf: Add a test with a bpf program with btf_tag attributes
  selftests/bpf: Test BTF_KIND_TAG for deduplication
  selftests/bpf: Add BTF_KIND_TAG unit tests
  selftests/bpf: Change NAME_NTH/IS_NAME_NTH for BTF_KIND_TAG format
  selftests/bpf: Test libbpf API function btf__add_tag()
  bpftool: Add support for BTF_KIND_TAG
  libbpf: Add support for BTF_KIND_TAG
  libbpf: Rename btf_{hash,equal}_int to btf_{hash,equal}_int_tag
  ...
====================

Link: https://lore.kernel.org/r/20210917173738.3397064-1-ast@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

72165 is a 16nm process SoC with a 10/100 integrated Ethernet PHY,
create a new macro and set of functions for this different process type.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20210917181551.2836036-1-f.fainelli@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Clang warns twice:

drivers/ptp/ptp_ocp.c:2065:16: error: operator '?:' has lower precedence
than '&'; '&' will be evaluated first
[-Werror,-Wbitwise-conditional-parentheses]
                           on & map ? " ON" : "OFF", src);
                           ~~~~~~~~ ^
drivers/ptp/ptp_ocp.c:2065:16: note: place parentheses around the '&'
expression to silence this warning
                           on & map ? " ON" : "OFF", src);
                                    ^
                           (       )
drivers/ptp/ptp_ocp.c:2065:16: note: place parentheses around the '?:'
expression to evaluate it first
                           on & map ? " ON" : "OFF", src);
                                    ^

on and map are both booleans so this should be a logical AND, which
clears up the operator precedence issue.

Fixes: a62a56d0 ("ptp: ocp: Enable 4th timestamper / PPS generator")
Link: https://github.com/ClangBuiltLinux/linux/issues/1457Suggested-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Link: https://lore.kernel.org/r/20210917045204.1385801-1-nathan@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

With clang building selftests/bpf, I hit a few warnings like below:

  .../bpf_iter.c:592:48: warning: variable 'expected_key_c' set but not used [-Wunused-but-set-variable]
  __u32 expected_key_a = 0, expected_key_b = 0, expected_key_c = 0;
                                                ^

  .../bpf_iter.c:688:48: warning: variable 'expected_key_c' set but not used [-Wunused-but-set-variable]
  __u32 expected_key_a = 0, expected_key_b = 0, expected_key_c = 0;
                                                ^

  .../tc_redirect.c:657:6: warning: variable 'target_fd' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
  if (!ASSERT_OK_PTR(nstoken, "setns " NS_FWD))
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  .../tc_redirect.c:743:6: note: uninitialized use occurs here
  if (target_fd >= 0)
      ^~~~~~~~~

Removing unused variables and initializing the previously-uninitialized variable
to ensure these warnings are gone.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210917043343.3711917-1-yhs@fb.com

Andrii Nakryiko says:

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

This patch set deprecates bpf_object_open_opts.attach_prog_fd (in libbpf 0.7+)
by extending bpf_program__set_attach_target() to support some more flexible
scenarios. Existing fexit_bpf2bpf selftest is updated accordingly to not use
deprecated APIs.

While at it, also deprecate no-op relaxed_core_relocs option (they are always
"relaxed").

Last patch also const-ifies all high-level libbpf attach APIs, as there is no
reason for them to assume bpf_program/bpf_map modifications.

Patch #1 also removes one more unneeded use of find_sec_def(), relying on
prog->sec_def that's set during bpf_object__open() operation, simplifying
upcoming refactoring a little bit more.

All these changes are preparatory patches before SEC() handling refactoring
that will come next.
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>