commit 18c602de ("qede: Use NETIF_F_GRO_HW.") introduced
a regression in driver that when xdp program is installed on
qede device, device's aggregation feature (hardware GRO) is not
getting disabled, which is unexpected with xdp.

Fixes: 18c602de ("qede: Use NETIF_F_GRO_HW.")
Signed-off-by: NManish Chopra <manishc@marvell.com>
Signed-off-by: NAriel Elior <aelior@marvell.com>
Reviewed-by: NMichael Chan <michael.chan@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Arthur Kiyanovski says:

====================
ena: fixes of interrupt moderation bugs

Differences from V1:
1. Updated default tx interrupt moderation to 64us
2. Added "Fixes:" tags.
3. Removed cosmetic changes that are not relevant for these bug fixes

This patchset includes a couple of fixes of bugs in the implemenation of
interrupt moderation.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Issue 1:
--------
Reproduction steps:
1. sudo ethtool -C eth0 rx-usecs 128
2. sudo ethtool -C eth0 adaptive-rx on
3. sudo ethtool -C eth0 adaptive-rx off
4. ethtool -c eth0

expected output: rx-usecs 128
actual output: rx-usecs 0

Reason for issue:
In stage 3, ethtool userspace calls first the ena_get_coalesce() handler
to get the current value of all properties, and then the ena_set_coalesce()
handler. When ena_get_coalesce() is called the adaptive interrupt
moderation is still on. There is an if in the code that returns the
rx_coalesce_usecs only if the adaptive interrupt moderation is off.
And since it is still on, rx_coalesce_usecs is not set, meaning it
stays 0.

Solution to issue:
Remove this if static interrupt moderation intervals have nothing to do
with dynamic ones.

Issue 2:
--------
Reproduction steps:
1. sudo ethtool -C eth0 adaptive-rx on
2. sudo ethtool -C eth0 rx-usecs 128
3. ethtool -c eth0

expected output: rx-usecs 128
actual output: rx-usecs 0

Reason for issue:
In stage 2, when ena_set_coalesce() is called, the handler tests if
rx adaptive interrupt moderation is on, and if it is, it returns before
getting to the part in the function that sets the rx non-adaptive
interrupt moderation interval.

Solution to issue:
Remove the return from the function when rx adaptive interrupt moderation
is on.

Also cleaned up the fixed code in ena_set_coalesce by grouping together
adaptive interrupt moderation toggling, and using && instead of nested
ifs.

Fixes: b3db86dc ("net: ena: reimplement set/get_coalesce()")
Fixes: 0eda8479 ("net: ena: fix retrieval of nonadaptive interrupt moderation intervals")
Fixes: 1738cd3e ("net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)")
Signed-off-by: NArthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Current default non-adaptive tx interrupt moderation interval is 196 us.
This value is too high and might cause the tx queue to fill up.

In this commit we set the default non-adaptive tx interrupt moderation
interval to 64 us in order to:
1. Reduce the probability of the queue filling-up (when compared to the
   current default value of 196 us).
2. Reduce unnecessary tx interrupt overhead (which happens if we set the
   default tx interval to 0).
   We determined experimentally that 64 us is an optimal value that
   reduces interrupt rate by more than 20% without affecting performance.

Fixes: 1738cd3e ("net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)")
Signed-off-by: NArthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the reboot_event handler, unregister the ib devices and enable
the IB layer to release the devices before the reboot.

Fixes: a33a803c ("net/smc: guarantee removal of link groups in reboot")
Signed-off-by: NKarsten Graul <kgraul@linux.ibm.com>
Reviewed-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current implementation of "stmmac_dt_phy" function initializes
the MDIO platform bus data, even in the absence of PHY. This fix
will skip MDIO initialization if there is no PHY present.

Fixes: 74371272 ("net: stmmac: Convert to phylink and remove phylib logic")
Acked-by: NJayati Sahu <jayati.sahu@samsung.com>
Signed-off-by: NSriram Dash <sriram.dash@samsung.com>
Signed-off-by: NPadmanabhan Rajanbabu <p.rajanbabu@samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a frame with NULL DSAP is received, llc_station_rcv is called.
In turn, llc_stat_ev_rx_null_dsap_xid_c is called to check if it is a NULL
XID frame. The return statement of llc_stat_ev_rx_null_dsap_xid_c returns 1
when the incoming frame is not a NULL XID frame and 0 otherwise. Hence, a
NULL XID response is returned unexpectedly, e.g. when the incoming frame is
a NULL TEST command.

To fix the error, simply remove the conditional operator.

A similar error in llc_stat_ev_rx_null_dsap_test_c is also fixed.
Signed-off-by: NChan Shu Tak, Alex <alexchan@task.com.hk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When doing stress test, we get the following trace:
kernel BUG at lib/dynamic_queue_limits.c:26!
Internal error: Oops - BUG: 0 [#1] SMP ARM
Modules linked in: hip04_eth
CPU: 0 PID: 2003 Comm: tDblStackPcap0 Tainted: G           O L  4.4.197 #1
Hardware name: Hisilicon A15
task: c3637668 task.stack: de3bc000
PC is at dql_completed+0x18/0x154
LR is at hip04_tx_reclaim+0x110/0x174 [hip04_eth]
pc : [<c041abfc>]    lr : [<bf0003a8>]    psr: 800f0313
sp : de3bdc2c  ip : 00000000  fp : c020fb10
r10: 00000000  r9 : c39b4224  r8 : 00000001
r7 : 00000046  r6 : c39b4000  r5 : 0078f392  r4 : 0078f392
r3 : 00000047  r2 : 00000000  r1 : 00000046  r0 : df5d5c80
Flags: Nzcv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 32c5387d  Table: 1e189b80  DAC: 55555555
Process tDblStackPcap0 (pid: 2003, stack limit = 0xde3bc190)
Stack: (0xde3bdc2c to 0xde3be000)
[<c041abfc>] (dql_completed) from [<bf0003a8>] (hip04_tx_reclaim+0x110/0x174 [hip04_eth])
[<bf0003a8>] (hip04_tx_reclaim [hip04_eth]) from [<bf0012c0>] (hip04_rx_poll+0x20/0x388 [hip04_eth])
[<bf0012c0>] (hip04_rx_poll [hip04_eth]) from [<c04c8d9c>] (net_rx_action+0x120/0x374)
[<c04c8d9c>] (net_rx_action) from [<c021eaf4>] (__do_softirq+0x218/0x318)
[<c021eaf4>] (__do_softirq) from [<c021eea0>] (irq_exit+0x88/0xac)
[<c021eea0>] (irq_exit) from [<c0240130>] (msa_irq_exit+0x11c/0x1d4)
[<c0240130>] (msa_irq_exit) from [<c0267ba8>] (__handle_domain_irq+0x110/0x148)
[<c0267ba8>] (__handle_domain_irq) from [<c0201588>] (gic_handle_irq+0xd4/0x118)
[<c0201588>] (gic_handle_irq) from [<c0558360>] (__irq_svc+0x40/0x58)
Exception stack(0xde3bdde0 to 0xde3bde28)
dde0: 00000000 00008001 c3637668 00000000 00000000 a00f0213 dd3627a0 c0af6380
de00: c086d380 a00f0213 c0a22a50 de3bde6c 00000002 de3bde30 c0558138 c055813c
de20: 600f0213 ffffffff
[<c0558360>] (__irq_svc) from [<c055813c>] (_raw_spin_unlock_irqrestore+0x44/0x54)
Kernel panic - not syncing: Fatal exception in interrupt

Pre-modification code:
int hip04_mac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
{
[...]
[1]	priv->tx_head = TX_NEXT(tx_head);
[2]	count++;
[3]	netdev_sent_queue(ndev, skb->len);
[...]
}
An rx interrupt occurs if hip04_mac_start_xmit just executes to the line 2,
tx_head has been updated, but corresponding 'skb->len' has not been
added to dql_queue.

And then
hip04_mac_interrupt->__napi_schedule->hip04_rx_poll->hip04_tx_reclaim

In hip04_tx_reclaim, because tx_head has been updated,
bytes_compl will plus an additional "skb-> len"
which has not been added to dql_queue. And then
trigger the BUG_ON(bytes_compl > num_queued - dql->num_completed).

To solve the problem described above, we put
"netdev_sent_queue(ndev, skb->len);"
before
"priv->tx_head = TX_NEXT(tx_head);"

Fixes: a41ea46a ("net: hisilicon: new hip04 ethernet driver")
Signed-off-by: NJiangfeng Xiao <xiaojiangfeng@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove special taglen define KSZ8795_INGRESS_TAG_LEN
and use generic KSZ_INGRESS_TAG_LEN instead.
Signed-off-by: NMichael Grzeschik <m.grzeschik@pengutronix.de>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Julian Wiedmann says:

====================
s390/qeth: fixes 2019-12-18

please apply the following patch series to your net tree.
This brings two fixes for initialization / teardown issues, and one
ENOTSUPP cleanup.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ENOTSUPP is not uapi, use EOPNOTSUPP instead.

Fixes: d66cb37e ("qeth: Add new priority queueing options")
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When managing the promiscuous mode during an RX modeset, qeth caches the
current HW state to avoid repeated programming of the same state on each
modeset.

But while tearing down a device, we forget to clear the cached state. So
when the device is later set online again, the initial RX modeset
doesn't program the promiscuous mode since we believe it is already
enabled.
Fix this by clearing the cached state in the tear-down path.

Note that for the SBP variant of promiscuous mode, this accidentally
works right now because we unconditionally restore the SBP role while
re-initializing.

Fixes: 4a71df50 ("qeth: new qeth device driver")
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: NAlexandra Winter <wintera@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Along with z/VM NICs, there's additional device types that only support
a specific transport mode (eg. external-bridged IQD).
Identify the corresponding error code, and raise a fitting error message
so that the user knows to adjust their device configuration.

On top of that also fix the subsequent error path, so that the rejected
cmd doesn't need to wait for a timeout but gets cancelled straight away.

Fixes: 4a71df50 ("qeth: new qeth device driver")
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Properly initialize refcount to 1 when hardware queue arrays for
TC-MQPRIO offload have been freshly allocated. Otherwise, following
warning is observed. Also fix up error path to only free hardware
queue arrays when refcount reaches 0.

[  130.075342] ------------[ cut here ]------------
[  130.075343] refcount_t: addition on 0; use-after-free.
[  130.075355] WARNING: CPU: 0 PID: 10870 at lib/refcount.c:25
refcount_warn_saturate+0xe1/0x100
[  130.075356] Modules linked in: sch_mqprio iptable_nat ib_iser
libiscsi scsi_transport_iscsi ib_ipoib rdma_ucm ib_umad iw_cxgb4 libcxgb
ib_uverbs x86_pkg_temp_thermal cxgb4 igb
[  130.075361] CPU: 0 PID: 10870 Comm: tc Kdump: loaded Not tainted
5.5.0-rc1+ #11
[  130.075362] Hardware name: Supermicro
X9SRE/X9SRE-3F/X9SRi/X9SRi-3F/X9SRE/X9SRE-3F/X9SRi/X9SRi-3F, BIOS 3.2
01/16/2015
[  130.075363] RIP: 0010:refcount_warn_saturate+0xe1/0x100
[  130.075364] Code: e8 14 41 c1 ff 0f 0b c3 80 3d 44 f4 10 01 00 0f 85
63 ff ff ff 48 c7 c7 38 9f 83 8c 31 c0 c6 05 2e f4 10 01 01 e8 ef 40 c1
ff <0f> 0b c3 48 c7 c7 10 9f 83 8c 31 c0 c6 05 17 f4 10 01 01 e8 d7 40
[  130.075365] RSP: 0018:ffffa48d00c0b768 EFLAGS: 00010286
[  130.075366] RAX: 0000000000000000 RBX: 0000000000000008 RCX:
0000000000000001
[  130.075366] RDX: 0000000000000001 RSI: 0000000000000096 RDI:
ffff8a2e9fa187d0
[  130.075367] RBP: ffff8a2e93890000 R08: 0000000000000398 R09:
000000000000003c
[  130.075367] R10: 00000000000142a0 R11: 0000000000000397 R12:
ffffa48d00c0b848
[  130.075368] R13: ffff8a2e94746498 R14: ffff8a2e966f7000 R15:
0000000000000031
[  130.075368] FS:  00007f689015f840(0000) GS:ffff8a2e9fa00000(0000)
knlGS:0000000000000000
[  130.075369] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  130.075369] CR2: 00000000006762a0 CR3: 00000007cf164005 CR4:
00000000001606f0
[  130.075370] Call Trace:
[  130.075377]  cxgb4_setup_tc_mqprio+0xbee/0xc30 [cxgb4]
[  130.075382]  ? cxgb4_ethofld_restart+0x50/0x50 [cxgb4]
[  130.075384]  ? pfifo_fast_init+0x7e/0xf0
[  130.075386]  mqprio_init+0x5f4/0x630 [sch_mqprio]
[  130.075389]  qdisc_create+0x1bf/0x4a0
[  130.075390]  tc_modify_qdisc+0x1ff/0x770
[  130.075392]  rtnetlink_rcv_msg+0x28b/0x350
[  130.075394]  ? rtnl_calcit.isra.32+0x110/0x110
[  130.075395]  netlink_rcv_skb+0xc6/0x100
[  130.075396]  netlink_unicast+0x1db/0x330
[  130.075397]  netlink_sendmsg+0x2f5/0x460
[  130.075399]  ? _copy_from_user+0x2e/0x60
[  130.075400]  sock_sendmsg+0x59/0x70
[  130.075401]  ____sys_sendmsg+0x1f0/0x230
[  130.075402]  ? copy_msghdr_from_user+0xd7/0x140
[  130.075403]  ___sys_sendmsg+0x77/0xb0
[  130.075404]  ? ___sys_recvmsg+0x84/0xb0
[  130.075406]  ? __handle_mm_fault+0x377/0xaf0
[  130.075407]  __sys_sendmsg+0x53/0xa0
[  130.075409]  do_syscall_64+0x44/0x130
[  130.075412]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  130.075413] RIP: 0033:0x7f688f13af10
[  130.075414] Code: c3 48 8b 05 82 6f 2c 00 f7 db 64 89 18 48 83 cb ff
eb dd 0f 1f 80 00 00 00 00 83 3d 8d d0 2c 00 00 75 10 b8 2e 00 00 00 0f
05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ae cc 00 00 48 89 04 24
[  130.075414] RSP: 002b:00007ffe6c7d9988 EFLAGS: 00000246 ORIG_RAX:
000000000000002e
[  130.075415] RAX: ffffffffffffffda RBX: 00000000006703a0 RCX:
00007f688f13af10
[  130.075415] RDX: 0000000000000000 RSI: 00007ffe6c7d99f0 RDI:
0000000000000003
[  130.075416] RBP: 000000005df38312 R08: 0000000000000002 R09:
0000000000008000
[  130.075416] R10: 00007ffe6c7d93e0 R11: 0000000000000246 R12:
0000000000000000
[  130.075417] R13: 00007ffe6c7e9c50 R14: 0000000000000001 R15:
000000000067c600
[  130.075418] ---[ end trace 8fbb3bf36a8671db ]---

v2:
- Move the refcount_set() closer to where the hardware queue arrays
  are being allocated.
- Fix up error path to only free hardware queue arrays when refcount
  reaches 0.

Fixes: 2d0cb84d ("cxgb4: add ETHOFLD hardware queue support")
Signed-off-by: NRahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Davide Caratti says:

====================
net/sched: cls_u32: fix refcount leak

a refcount leak in the error path of u32_change() has been recently
introduced. It can be observed with the following commands:

  [root@f31 ~]# tc filter replace dev eth0 ingress protocol ip prio 97 \
  > u32 match ip src 127.0.0.1/32 indev notexist20 flowid 1:1 action drop
  RTNETLINK answers: Invalid argument
  We have an error talking to the kernel
  [root@f31 ~]# tc filter replace dev eth0 ingress protocol ip prio 98 \
  > handle 42:42 u32 divisor 256
  Error: cls_u32: Divisor can only be used on a hash table.
  We have an error talking to the kernel
  [root@f31 ~]# tc filter replace dev eth0 ingress protocol ip prio 99 \
  > u32 ht 47:47
  Error: cls_u32: Specified hash table not found.
  We have an error talking to the kernel

they all legitimately return -EINVAL; however, they leave semi-configured
filters at eth0 tc ingress:

 [root@f31 ~]# tc filter show dev eth0 ingress
 filter protocol ip pref 97 u32 chain 0
 filter protocol ip pref 97 u32 chain 0 fh 800: ht divisor 1
 filter protocol ip pref 98 u32 chain 0
 filter protocol ip pref 98 u32 chain 0 fh 801: ht divisor 1
 filter protocol ip pref 99 u32 chain 0
 filter protocol ip pref 99 u32 chain 0 fh 802: ht divisor 1

With older kernels, filters were unconditionally considered empty (and
thus de-refcounted) on the error path of ->change().
After commit 8b64678e ("net: sched: refactor tp insert/delete for
concurrent execution"), filters were considered empty when the walk()
function didn't set 'walker.stop' to 1.
Finally, with commit 6676d5e4 ("net: sched: set dedicated tcf_walker
flag when tp is empty"), tc filters are considered empty unless the walker
function is called with a non-NULL handle. This last change doesn't fit
cls_u32 design, because at least the "root hnode" is (almost) always
non-NULL, as it's allocated in u32_init().

- patch 1/2 is a proposal to restore the original kernel behavior, where
  no filter was installed in the error path of u32_change().
- patch 2/2 adds tdc selftests that can be ued to verify the correct
  behavior of u32 in the error path of ->change().
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

- move test "e9a3 - Add u32 with source match" to u32.json, and change the
  match pattern to catch all hnodes
- add testcases for relevant error paths of cls_u32 module
Signed-off-by: NDavide Caratti <dcaratti@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

when users replace cls_u32 filters with new ones having wrong parameters,
so that u32_change() fails to validate them, the kernel doesn't roll-back
correctly, and leaves semi-configured rules.

Fix this in u32_walk(), avoiding a call to the walker function on filters
that don't have a match rule connected. The side effect is, these "empty"
filters are not even dumped when present; but that shouldn't be a problem
as long as we are restoring the original behaviour, where semi-configured
filters were not even added in the error path of u32_change().

Fixes: 6676d5e4 ("net: sched: set dedicated tcf_walker flag when tp is empty")
Signed-off-by: NDavide Caratti <dcaratti@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In s3fwrn5_fw_recv_frame, if fw_info->rsp is not empty, the
current code causes a crash via BUG_ON. However, s3fwrn5_fw_send_msg
does not crash in such a scenario. The patch replaces the BUG_ON
by returning the error to the callers and frees up skb.
Signed-off-by: NAditya Pakki <pakki001@umn.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Antoine Tenart says:

====================
net: macb: fix probing of PHY not described in the dt

The macb Ethernet driver supports various ways of referencing its
network PHY. When a device tree is used the PHY can be referenced with
a phy-handle or, if connected to its internal MDIO bus, described in
a child node. Some platforms omitted the PHY description while
connecting the PHY to the internal MDIO bus and in such cases the MDIO
bus has to be scanned "manually" by the macb driver.

Prior to the phylink conversion the driver registered the MDIO bus with
of_mdiobus_register and then in case the PHY couldn't be retrieved
using dt or using phy_find_first (because registering an MDIO bus with
of_mdiobus_register masks all PHYs) the macb driver was "manually"
scanning the MDIO bus (like mdiobus_register does). The phylink
conversion did break this particular case but reimplementing the manual
scan of the bus in the macb driver wouldn't be very clean. The solution
seems to be registering the MDIO bus based on if the PHYs are described
in the device tree or not.

There are multiple ways to do this, none is perfect. I chose to check if
any of the child nodes of the macb node was a network PHY and based on
this to register the MDIO bus with the of_ helper or not. The drawback
is boards referencing the PHY through phy-handle, would scan the entire
MDIO bus of the macb at boot time (as the MDIO bus would be registered
with mdiobus_register). For this solution to work properly
of_mdiobus_child_is_phy has to be exported, which means the patch doing
so has to be backported to -stable as well.

Another possible solution could have been to simply check if the macb
node has a child node by counting its sub-nodes. This isn't techically
perfect, as there could be other sub-nodes (in practice this should be
fine, fixed-link being taken care of in the driver). We could also
simply s/of_mdiobus_register/mdiobus_register/ but that could break
boards using the PHY description in child node as a selector (which
really would be not a proper way to do this...).

The real issue here being having PHYs not described in the dt but we
have dt backward compatibility, so we have to live with that.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes the case where the PHY isn't described in the device
tree. This is due to the way the MDIO bus is registered in the driver:
whether the PHY is described in the device tree or not, the bus is
registered through of_mdiobus_register. The function masks all the PHYs
and only allow probing the ones described in the device tree. Prior to
the Phylink conversion this was also done but later on in the driver
the MDIO bus was manually scanned to circumvent the fact that the PHY
wasn't described.

This patch fixes it in a proper way, by registering the MDIO bus based
on if the PHY attached to a given interface is described in the device
tree or not.

Fixes: 7897b071 ("net: macb: convert to phylink")
Signed-off-by: NAntoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch exports of_mdiobus_child_is_phy, allowing to check if a child
node is a network PHY.
Signed-off-by: NAntoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Daniel Borkmann says:

====================
pull-request: bpf 2019-12-19

The following pull-request contains BPF updates for your *net* tree.

We've added 10 non-merge commits during the last 8 day(s) which contain
a total of 21 files changed, 269 insertions(+), 108 deletions(-).

The main changes are:

1) Fix lack of synchronization between xsk wakeup and destroying resources
   used by xsk wakeup, from Maxim Mikityanskiy.

2) Fix pruning with tail call patching, untrack programs in case of verifier
   error and fix a cgroup local storage tracking bug, from Daniel Borkmann.

3) Fix clearing skb->tstamp in bpf_redirect() when going from ingress to
   egress which otherwise cause issues e.g. on fq qdisc, from Lorenz Bauer.

4) Fix compile warning of unused proc_dointvec_minmax_bpf_restricted() when
   only cBPF is present, from Alexander Lobakin.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Expand dummy prog generation such that we can easily check on return
codes and add few more test cases to make sure we keep on tracking
pruning behavior.

  # ./test_verifier
  [...]
  #1066/p XDP pkt read, pkt_data <= pkt_meta', bad access 1 OK
  #1067/p XDP pkt read, pkt_data <= pkt_meta', bad access 2 OK
  Summary: 1580 PASSED, 0 SKIPPED, 0 FAILED

Also verified that JIT dump of added test cases looks good.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/df7200b6021444fd369376d227de917357285b65.1576789878.git.daniel@iogearbox.net

While testing Cilium with /unreleased/ Linus' tree under BPF-based NodePort
implementation, I noticed a strange BPF SNAT engine behavior from time to
time. In some cases it would do the correct SNAT/DNAT service translation,
but at a random point in time it would just stop and perform an unexpected
translation after SYN, SYN/ACK and stack would send a RST back. While initially
assuming that there is some sort of a race condition in BPF code, adding
trace_printk()s for debugging purposes at some point seemed to have resolved
the issue auto-magically.

Digging deeper on this Heisenbug and reducing the trace_printk() calls to
an absolute minimum, it turns out that a single call would suffice to
trigger / not trigger the seen RST issue, even though the logic of the
program itself remains unchanged. Turns out the single call changed verifier
pruning behavior to get everything to work. Reconstructing a minimal test
case, the incorrect JIT dump looked as follows:

  # bpftool p d j i 11346
  0xffffffffc0cba96c:
  [...]
    21:   movzbq 0x30(%rdi),%rax
    26:   cmp    $0xd,%rax
    2a:   je     0x000000000000003a
    2c:   xor    %edx,%edx
    2e:   movabs $0xffff89cc74e85800,%rsi
    38:   jmp    0x0000000000000049
    3a:   mov    $0x2,%edx
    3f:   movabs $0xffff89cc74e85800,%rsi
    49:   mov    -0x224(%rbp),%eax
    4f:   cmp    $0x20,%eax
    52:   ja     0x0000000000000062
    54:   add    $0x1,%eax
    57:   mov    %eax,-0x224(%rbp)
    5d:   jmpq   0xffffffffffff6911
    62:   mov    $0x1,%eax
  [...]

Hence, unexpectedly, JIT emitted a direct jump even though retpoline based
one would have been needed since in line 2c and 3a we have different slot
keys in BPF reg r3. Verifier log of the test case reveals what happened:

  0: (b7) r0 = 14
  1: (73) *(u8 *)(r1 +48) = r0
  2: (71) r0 = *(u8 *)(r1 +48)
  3: (15) if r0 == 0xd goto pc+4
   R0_w=inv(id=0,umax_value=255,var_off=(0x0; 0xff)) R1=ctx(id=0,off=0,imm=0) R10=fp0
  4: (b7) r3 = 0
  5: (18) r2 = 0xffff89cc74d54a00
  7: (05) goto pc+3
  11: (85) call bpf_tail_call#12
  12: (b7) r0 = 1
  13: (95) exit
  from 3 to 8: R0_w=inv13 R1=ctx(id=0,off=0,imm=0) R10=fp0
  8: (b7) r3 = 2
  9: (18) r2 = 0xffff89cc74d54a00
  11: safe
  processed 13 insns (limit 1000000) [...]

Second branch is pruned by verifier since considered safe, but issue is that
record_func_key() couldn't have seen the index in line 3a and therefore
decided that emitting a direct jump at this location was okay.

Fix this by reusing our backtracking logic for precise scalar verification
in order to prevent pruning on the slot key. This means verifier will track
content of r3 all the way backwards and only prune if both scalars were
unknown in state equivalence check and therefore poisoned in the first place
in record_func_key(). The range is [x,x] in record_func_key() case since
the slot always would have to be constant immediate. Correct verification
after fix:

  0: (b7) r0 = 14
  1: (73) *(u8 *)(r1 +48) = r0
  2: (71) r0 = *(u8 *)(r1 +48)
  3: (15) if r0 == 0xd goto pc+4
   R0_w=invP(id=0,umax_value=255,var_off=(0x0; 0xff)) R1=ctx(id=0,off=0,imm=0) R10=fp0
  4: (b7) r3 = 0
  5: (18) r2 = 0x0
  7: (05) goto pc+3
  11: (85) call bpf_tail_call#12
  12: (b7) r0 = 1
  13: (95) exit
  from 3 to 8: R0_w=invP13 R1=ctx(id=0,off=0,imm=0) R10=fp0
  8: (b7) r3 = 2
  9: (18) r2 = 0x0
  11: (85) call bpf_tail_call#12
  12: (b7) r0 = 1
  13: (95) exit
  processed 15 insns (limit 1000000) [...]

And correct corresponding JIT dump:

  # bpftool p d j i 11
  0xffffffffc0dc34c4:
  [...]
    21:	  movzbq 0x30(%rdi),%rax
    26:	  cmp    $0xd,%rax
    2a:	  je     0x000000000000003a
    2c:	  xor    %edx,%edx
    2e:	  movabs $0xffff9928b4c02200,%rsi
    38:	  jmp    0x0000000000000049
    3a:	  mov    $0x2,%edx
    3f:	  movabs $0xffff9928b4c02200,%rsi
    49:	  cmp    $0x4,%rdx
    4d:	  jae    0x0000000000000093
    4f:	  and    $0x3,%edx
    52:	  mov    %edx,%edx
    54:	  cmp    %edx,0x24(%rsi)
    57:	  jbe    0x0000000000000093
    59:	  mov    -0x224(%rbp),%eax
    5f:	  cmp    $0x20,%eax
    62:	  ja     0x0000000000000093
    64:	  add    $0x1,%eax
    67:	  mov    %eax,-0x224(%rbp)
    6d:	  mov    0x110(%rsi,%rdx,8),%rax
    75:	  test   %rax,%rax
    78:	  je     0x0000000000000093
    7a:	  mov    0x30(%rax),%rax
    7e:	  add    $0x19,%rax
    82:   callq  0x000000000000008e
    87:   pause
    89:   lfence
    8c:   jmp    0x0000000000000087
    8e:   mov    %rax,(%rsp)
    92:   retq
    93:   mov    $0x1,%eax
  [...]

Also explicitly adding explicit env->allow_ptr_leaks to fixup_bpf_calls() since
backtracking is enabled under former (direct jumps as well, but use different
test). In case of only tracking different map pointers as in c93552c4 ("bpf:
properly enforce index mask to prevent out-of-bounds speculation"), pruning
cannot make such short-cuts, neither if there are paths with scalar and non-scalar
types as r3. mark_chain_precision() is only needed after we know that
register_is_const(). If it was not the case, we already poison the key on first
path and non-const key in later paths are not matching the scalar range in regsafe()
either. Cilium NodePort testing passes fine as well now. Note, released kernels
not affected.

Fixes: d2e4c1e6 ("bpf: Constant map key tracking for prog array pokes")
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/ac43ffdeb7386c5bd688761ed266f3722bb39823.1576789878.git.daniel@iogearbox.net

proc_dointvec_minmax_bpf_restricted() has been firstly introduced
in commit 2e4a3098 ("bpf: restrict access to core bpf sysctls")
under CONFIG_HAVE_EBPF_JIT. Then, this ifdef has been removed in
ede95a63 ("bpf: add bpf_jit_limit knob to restrict unpriv
allocations"), because a new sysctl, bpf_jit_limit, made use of it.
Finally, this parameter has become long instead of integer with
fdadd049 ("bpf: fix bpf_jit_limit knob for PAGE_SIZE >= 64K")
and thus, a new proc_dolongvec_minmax_bpf_restricted() has been
added.

With this last change, we got back to that
proc_dointvec_minmax_bpf_restricted() is used only under
CONFIG_HAVE_EBPF_JIT, but the corresponding ifdef has not been
brought back.

So, in configurations like CONFIG_BPF_JIT=y && CONFIG_HAVE_EBPF_JIT=n
since v4.20 we have:

  CC      net/core/sysctl_net_core.o
net/core/sysctl_net_core.c:292:1: warning: ‘proc_dointvec_minmax_bpf_restricted’ defined but not used [-Wunused-function]
  292 | proc_dointvec_minmax_bpf_restricted(struct ctl_table *table, int write,
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Suppress this by guarding it with CONFIG_HAVE_EBPF_JIT again.

Fixes: fdadd049 ("bpf: fix bpf_jit_limit knob for PAGE_SIZE >= 64K")
Signed-off-by: NAlexander Lobakin <alobakin@dlink.ru>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191218091821.7080-1-alobakin@dlink.ru

Maxim Mikityanskiy says:

====================
This series addresses the issue described in the commit message of the
first patch: lack of synchronization between XSK wakeup and destroying
the resources used by XSK wakeup. The idea is similar to napi_synchronize.
The series contains fixes for the drivers that implement XSK.

v2 incorporates changes suggested by Björn:

1. Call synchronize_rcu in Intel drivers only if the XDP program is
   being unloaded.
2. Don't forget rcu_read_lock when wakeup is called from xsk_poll.
3. Use xs->zc as the condition to call ndo_xsk_wakeup.
====================
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Use synchronize_rcu to wait until the XSK wakeup function finishes
before destroying the resources it uses:

1. ixgbe_down already calls synchronize_rcu after setting __IXGBE_DOWN.

2. After switching the XDP program, call synchronize_rcu to let
ixgbe_xsk_wakeup exit before the XDP program is freed.

3. Changing the number of channels brings the interface down.

4. Disabling UMEM sets __IXGBE_TX_DISABLED before closing hardware
resources and resetting xsk_umem. Check that bit in ixgbe_xsk_wakeup to
avoid using the XDP ring when it's already destroyed. synchronize_rcu is
called from ixgbe_txrx_ring_disable.
Signed-off-by: NMaxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: NBjörn Töpel <bjorn.topel@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191217162023.16011-5-maximmi@mellanox.com

Use synchronize_rcu to wait until the XSK wakeup function finishes
before destroying the resources it uses:

1. i40e_down already calls synchronize_rcu. On i40e_down either
__I40E_VSI_DOWN or __I40E_CONFIG_BUSY is set. Check the latter in
i40e_xsk_wakeup (the former is already checked there).

2. After switching the XDP program, call synchronize_rcu to let
i40e_xsk_wakeup exit before the XDP program is freed.

3. Changing the number of channels brings the interface down (see
i40e_prep_for_reset and i40e_pf_quiesce_all_vsi).

4. Disabling UMEM sets __I40E_CONFIG_BUSY, too.
Signed-off-by: NMaxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: NBjörn Töpel <bjorn.topel@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191217162023.16011-4-maximmi@mellanox.com

After disabling resources necessary for XSK (the XDP program, channels,
XSK queues), use synchronize_rcu to wait until the XSK wakeup function
finishes, before freeing the resources.

Suspend XSK wakeups during switching channels. If the XDP program is
being removed, synchronize_rcu before closing the old channels to allow
XSK wakeup to complete.
Signed-off-by: NMaxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191217162023.16011-3-maximmi@mellanox.com

The XSK wakeup callback in drivers makes some sanity checks before
triggering NAPI. However, some configuration changes may occur during
this function that affect the result of those checks. For example, the
interface can go down, and all the resources will be destroyed after the
checks in the wakeup function, but before it attempts to use these
resources. Wrap this callback in rcu_read_lock to allow driver to
synchronize_rcu before actually destroying the resources.

xsk_wakeup is a new function that encapsulates calling ndo_xsk_wakeup
wrapped into the RCU lock. After this commit, xsk_poll starts using
xsk_wakeup and checks xs->zc instead of ndo_xsk_wakeup != NULL to decide
ndo_xsk_wakeup should be called. It also fixes a bug introduced with the
need_wakeup feature: a non-zero-copy socket may be used with a driver
supporting zero-copy, and in this case ndo_xsk_wakeup should not be
called, so the xs->zc check is the correct one.

Fixes: 77cd0d7b ("xsk: add support for need_wakeup flag in AF_XDP rings")
Signed-off-by: NMaxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: NBjörn Töpel <bjorn.topel@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191217162023.16011-2-maximmi@mellanox.com

Jose Abreu says:

====================
net: stmmac: Fixes for -net

Fixes for stmmac.

1) Fixes the filtering selftests (again) for cases when the number of multicast
filters are not enough.

2) Fixes SPH feature for MTU > default.

3) Fixes the behavior of accepting invalid MTU values.

4) Fixes FCS stripping for multi-descriptor packets.

5) Fixes the change of RX buffer size in XGMAC.

6) Fixes RX buffer size alignment.

7) Fixes the 16KB buffer alignment.

8) Fixes the enabling of 16KB buffer size feature.

9) Always arm the TX coalesce timer so that missed interrupts do not cause
a TX queue timeout.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If TX Coalesce timer is enabled we should always arm it, otherwise we
may hit the case where an interrupt is missed and the TX Queue will
timeout.

Arming the timer does not necessarly mean it will run the tx_clean()
because this function is wrapped around NAPI launcher.

Fixes: 9125cdd1 ("stmmac: add the initial tx coalesce schema")
Signed-off-by: NJose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

XGMAC supports maximum MTU that can go to 16KB. Lets add this check in
the calculation of RX buffer size.

Fixes: 7ac6653a ("stmmac: Move the STMicroelectronics driver")
Signed-off-by: NJose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The 16KB RX Buffer must also be 16 byte aligned. Fix it.

Fixes: 7ac6653a ("stmmac: Move the STMicroelectronics driver")
Signed-off-by: NJose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to align the RX buffer size to at least 16 byte so that IP
doesn't mis-behave. This is required by HW.

Changes from v2:
- Align UP and not DOWN (David)

Fixes: 7ac6653a ("stmmac: Move the STMicroelectronics driver")
Signed-off-by: NJose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When switching between buffer sizes we need to clear the previous value.

Fixes: d6ddfacd ("net: stmmac: Add DMA related callbacks for XGMAC2")
Signed-off-by: NJose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Only the last received buffer contains the FCS field. Check for end of
packet before trying to strip the FCS field.

Fixes: 88ebe2cf ("net: stmmac: Rework stmmac_rx()")
Signed-off-by: NJose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The maximum MTU value is determined by the maximum size of TX FIFO so
that a full packet can fit in the FIFO. Add a check for this in the MTU
change callback.

Also check if provided and rounded MTU does not passes the maximum limit
of 16K.

Changes from v2:
- Align MTU before checking if its valid

Fixes: 7ac6653a ("stmmac: Move the STMicroelectronics driver")
Signed-off-by: NJose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Split Header feature needs to know the size of RX buffer but current
code is determining it too late. Fix this by moving the RX buffer
computation to earlier stage.

Changes from v2:
- Do not try to align already aligned buffer size

Fixes: 67afd6d1 ("net: stmmac: Add Split Header support and enable it in XGMAC cores")
Signed-off-by: NJose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When running the MC and UC filter tests we setup a multicast address
that its expected to be blocked. If the number of available multicast
registers is zero, driver will always pass the multicast packets which
will fail the test.

Check if available multicast addresses is enough before running the
tests.

Fixes: 091810db ("net: stmmac: Introduce selftests support")
Signed-off-by: NJose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>