Pull RCU updates from Ingo Molnar:
"The main changes in this cycle were:
- Dynamic tick (nohz) updates, perhaps most notably changes to force
the tick on when needed due to lengthy in-kernel execution on CPUs
on which RCU is waiting.
- Linux-kernel memory consistency model updates.
- Replace rcu_swap_protected() with rcu_prepace_pointer().
- Torture-test updates.
- Documentation updates.
- Miscellaneous fixes"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
security/safesetid: Replace rcu_swap_protected() with rcu_replace_pointer()
net/sched: Replace rcu_swap_protected() with rcu_replace_pointer()
net/netfilter: Replace rcu_swap_protected() with rcu_replace_pointer()
net/core: Replace rcu_swap_protected() with rcu_replace_pointer()
bpf/cgroup: Replace rcu_swap_protected() with rcu_replace_pointer()
fs/afs: Replace rcu_swap_protected() with rcu_replace_pointer()
drivers/scsi: Replace rcu_swap_protected() with rcu_replace_pointer()
drm/i915: Replace rcu_swap_protected() with rcu_replace_pointer()
x86/kvm/pmu: Replace rcu_swap_protected() with rcu_replace_pointer()
rcu: Upgrade rcu_swap_protected() to rcu_replace_pointer()
rcu: Suppress levelspread uninitialized messages
rcu: Fix uninitialized variable in nocb_gp_wait()
rcu: Update descriptions for rcu_future_grace_period tracepoint
rcu: Update descriptions for rcu_nocb_wake tracepoint
rcu: Remove obsolete descriptions for rcu_barrier tracepoint
rcu: Ensure that ->rcu_urgent_qs is set before resched IPI
workqueue: Convert for_each_wq to use built-in list check
rcu: Several rcu_segcblist functions can be static
rcu: Remove unused function hlist_bl_del_init_rcu()
Documentation: Rename rcu_node_context_switch() to rcu_note_context_switch()
...
Minor conflict in drivers/s390/net/qeth_l2_main.c, kept the lock
from commit c8183f5489 ("s390/qeth: fix potential deadlock on
workqueue flush"), removed the code which was removed by commit
9897d583b0 ("s390/qeth: consolidate some duplicated HW cmd code").
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
ct_policy and mpls_policy are parsed with nla_parse_nested(), which
does NL_VALIDATE_STRICT validation, strict_start_type is not needed
to set as it is actually trying to make some attributes parsed with
NL_VALIDATE_STRICT.
This patch is to remove it, and do the same on rtm_nh_policy which
is parsed by nlmsg_parse().
Suggested-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is to allow matching options in erspan.
The options can be described in the form:
VER:INDEX:DIR:HWID/VER:INDEX_MASK:DIR_MASK:HWID_MASK.
When ver is set to 1, index will be applied while dir
and hwid will be ignored, and when ver is set to 2,
dir and hwid will be used while index will be ignored.
Different from geneve, only one option can be set. And
also, geneve options, vxlan options or erspan options
can't be set at the same time.
# ip link add name erspan1 type erspan external
# tc qdisc add dev erspan1 ingress
# tc filter add dev erspan1 protocol ip parent ffff: \
flower \
enc_src_ip 10.0.99.192 \
enc_dst_ip 10.0.99.193 \
enc_key_id 11 \
erspan_opts 1:12:0:0/1:ffff:0:0 \
ip_proto udp \
action mirred egress redirect dev eth0
v1->v2:
- improve some err msgs of extack.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is to allow matching gbp option in vxlan.
The options can be described in the form GBP/GBP_MASK,
where GBP is represented as a 32bit hexadecimal value.
Different from geneve, only one option can be set. And
also, geneve options and vxlan options can't be set at
the same time.
# ip link add name vxlan0 type vxlan dstport 0 external
# tc qdisc add dev vxlan0 ingress
# tc filter add dev vxlan0 protocol ip parent ffff: \
flower \
enc_src_ip 10.0.99.192 \
enc_dst_ip 10.0.99.193 \
enc_key_id 11 \
vxlan_opts 01020304/ffffffff \
ip_proto udp \
action mirred egress redirect dev eth0
v1->v2:
- add .strict_start_type for enc_opts_policy as Jakub noticed.
- use Duplicate instead of Wrong in err msg for extack as Jakub
suggested.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is to allow setting erspan options using the
act_tunnel_key action. Different from geneve options,
only one option can be set. And also, geneve options,
vxlan options or erspan options can't be set at the
same time.
Options are expressed as ver:index:dir:hwid, when ver
is set to 1, index will be applied while dir and hwid
will be ignored, and when ver is set to 2, dir and
hwid will be used while index will be ignored.
# ip link add name erspan1 type erspan external
# tc qdisc add dev eth0 ingress
# tc filter add dev eth0 protocol ip parent ffff: \
flower indev eth0 \
ip_proto udp \
action tunnel_key \
set src_ip 10.0.99.192 \
dst_ip 10.0.99.193 \
dst_port 6081 \
id 11 \
erspan_opts 1:2:0:0 \
action mirred egress redirect dev erspan1
v1->v2:
- do the validation when dst is not yet allocated as Jakub suggested.
- use Duplicate instead of Wrong in err msg for extack.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is to allow setting vxlan options using the
act_tunnel_key action. Different from geneve options,
only one option can be set. And also, geneve options
and vxlan options can't be set at the same time.
gbp is the only param for vxlan options:
# ip link add name vxlan0 type vxlan dstport 0 external
# tc qdisc add dev eth0 ingress
# tc filter add dev eth0 protocol ip parent ffff: \
flower indev eth0 \
ip_proto udp \
action tunnel_key \
set src_ip 10.0.99.192 \
dst_ip 10.0.99.193 \
dst_port 6081 \
id 11 \
vxlan_opts 01020304 \
action mirred egress redirect dev vxlan0
v1->v2:
- add .strict_start_type for enc_opts_policy as Jakub noticed.
- use Duplicate instead of Wrong in err msg for extack as Jakub
suggested.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
RFC 8033 suggests an alternative approach to calculate the queue
delay in PIE by using a timestamp on every enqueued packet. This
patch adds an implementation of that approach and sets it as the
default method to calculate queue delay. The previous method (based
on Little's law) to calculate queue delay is set as optional.
Signed-off-by: Gautam Ramakrishnan <gautamramk@gmail.com>
Signed-off-by: Leslie Monis <lesliemonis@gmail.com>
Signed-off-by: Mohit P. Tahiliani <tahiliani@nitk.edu.in>
Acked-by: Dave Taht <dave.taht@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The taprio qdisc allows to set mqprio setting but only once. In case
if mqprio settings are provided next time the error is returned as
it's not allowed to change traffic class mapping in-flignt and that
is normal. But if configuration is absolutely the same - no need to
return error. It allows to provide same command couple times,
changing only base time for instance, or changing only scheds maps,
but leaving mqprio setting w/o modification. It more corresponds the
message: "Changing the traffic mapping of a running schedule is not
supported", so reject mqprio if it's really changed.
Also corrected TC_BITMASK + 1 for consistency, as proposed.
Fixes: a3d43c0d56 ("taprio: Add support adding an admin schedule")
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
info->options_len is 'u8' type, and when opts_len with a value >
IP_TUNNEL_OPTS_MAX, 'info->options_len = opts_len' will cast int
to u8 and set a wrong value to info->options_len.
Kernel crashed in my test when doing:
# opts="0102:80:00800022"
# for i in {1..99}; do opts="$opts,0102:80:00800022"; done
# ip link add name geneve0 type geneve dstport 0 external
# tc qdisc add dev eth0 ingress
# tc filter add dev eth0 protocol ip parent ffff: \
flower indev eth0 ip_proto udp action tunnel_key \
set src_ip 10.0.99.192 dst_ip 10.0.99.193 \
dst_port 6081 id 11 geneve_opts $opts \
action mirred egress redirect dev geneve0
So we should do the similar check as cls_flower does, return error
when opts_len > IP_TUNNEL_OPTS_MAX in tunnel_key_copy_opts().
Fixes: 0ed5269f9e ("net/sched: add tunnel option support to act_tunnel_key")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
after commit 4097e9d250 ("net: sched: don't use tc_action->order during
action dump"), 'act->order' is initialized but then it's no more read, so
we can just remove this member of struct tc_action.
CC: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
One conflict in the BPF samples Makefile, some fixes in 'net' whilst
we were converting over to Makefile.target rules in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
sk->sk_max_ack_backlog can be read without any lock being held
at least in TCP/DCCP cases.
We need to use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing
and/or potential KCSAN warnings.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sk->sk_ack_backlog can be read without any lock being held.
We need to use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing
and/or potential KCSAN warnings.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now the kernel uses 64bit packet counters in scheduler layer,
we want to export these counters to user space.
Instead risking breaking user space by adding fields
to struct gnet_stats_basic, add a new TCA_STATS_PKT64.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After this change, qdisc packet counter is no longer
a 32bit quantity. We still export 32bit values to user.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a new filter is added to cls_api, the function
tcf_chain_tp_insert_unique() looks up the protocol/priority/chain to
determine if the tcf_proto is duplicated in the chain's hashtable. It then
creates a new entry or continues with an existing one. In cls_flower, this
allows the function fl_ht_insert_unque to determine if a filter is a
duplicate and reject appropriately, meaning that the duplicate will not be
passed to drivers via the offload hooks. However, when a tcf_proto is
destroyed it is removed from its chain before a hardware remove hook is
hit. This can lead to a race whereby the driver has not received the
remove message but duplicate flows can be accepted. This, in turn, can
lead to the offload driver receiving incorrect duplicate flows and out of
order add/delete messages.
Prevent duplicates by utilising an approach suggested by Vlad Buslov. A
hash table per block stores each unique chain/protocol/prio being
destroyed. This entry is only removed when the full destroy (and hardware
offload) has completed. If a new flow is being added with the same
identiers as a tc_proto being detroyed, then the add request is replayed
until the destroy is complete.
Fixes: 8b64678e0a ("net: sched: refactor tp insert/delete for concurrent execution")
Signed-off-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Reported-by: Louis Peens <louis.peens@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The same code which recognizes ICMP error packets is duplicated several
times. Use the icmp_is_err() and icmpv6_is_err() helpers instead, which
do the same thing.
ip_multipath_l3_keys() and tcf_nat_act() didn't check for all the error types,
assume that they should instead.
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't swap oper and admin schedules too early, it's not correct and
causes crash.
Steps to reproduce:
1)
tc qdisc replace dev eth0 parent root handle 100 taprio \
num_tc 3 \
map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 \
queues 1@0 1@1 1@2 \
base-time $SOME_BASE_TIME \
sched-entry S 01 80000 \
sched-entry S 02 15000 \
sched-entry S 04 40000 \
flags 2
2)
tc qdisc replace dev eth0 parent root handle 100 taprio \
base-time $SOME_BASE_TIME \
sched-entry S 01 90000 \
sched-entry S 02 20000 \
sched-entry S 04 40000 \
flags 2
3)
tc qdisc replace dev eth0 parent root handle 100 taprio \
base-time $SOME_BASE_TIME \
sched-entry S 01 150000 \
sched-entry S 02 200000 \
sched-entry S 04 40000 \
flags 2
Do 2 3 2 .. steps more times if not happens and observe:
[ 305.832319] Unable to handle kernel write to read-only memory at
virtual address ffff0000087ce7f0
[ 305.910887] CPU: 0 PID: 0 Comm: swapper/0 Not tainted
[ 305.919306] Hardware name: Texas Instruments AM654 Base Board (DT)
[...]
[ 306.017119] x1 : ffff800848031d88 x0 : ffff800848031d80
[ 306.022422] Call trace:
[ 306.024866] taprio_free_sched_cb+0x4c/0x98
[ 306.029040] rcu_process_callbacks+0x25c/0x410
[ 306.033476] __do_softirq+0x10c/0x208
[ 306.037132] irq_exit+0xb8/0xc8
[ 306.040267] __handle_domain_irq+0x64/0xb8
[ 306.044352] gic_handle_irq+0x7c/0x178
[ 306.048092] el1_irq+0xb0/0x128
[ 306.051227] arch_cpu_idle+0x10/0x18
[ 306.054795] do_idle+0x120/0x138
[ 306.058015] cpu_startup_entry+0x20/0x28
[ 306.061931] rest_init+0xcc/0xd8
[ 306.065154] start_kernel+0x3bc/0x3e4
[ 306.068810] Code: f2fbd5b7 f2fbd5b6 d503201f f9400422 (f9000662)
[ 306.074900] ---[ end trace 96c8e2284a9d9d6e ]---
[ 306.079507] Kernel panic - not syncing: Fatal exception in interrupt
[ 306.085847] SMP: stopping secondary CPUs
[ 306.089765] Kernel Offset: disabled
Try to explain one of the possible crash cases:
The "real" admin list is assigned when admin_sched is set to
new_admin, it happens after "swap", that assigns to oper_sched NULL.
Thus if call qdisc show it can crash.
Farther, next second time, when sched list is updated, the admin_sched
is not NULL and becomes the oper_sched, previous oper_sched was NULL so
just skipped. But then admin_sched is assigned new_admin, but schedules
to free previous assigned admin_sched (that already became oper_sched).
Farther, next third time, when sched list is updated,
while one more swap, oper_sched is not null, but it was happy to be
freed already (while prev. admin update), so while try to free
oper_sched the kernel panic happens at taprio_free_sched_cb().
So, move the "swap emulation" where it should be according to function
comment from code.
Fixes: 9c66d15646 ("taprio: Add support for hardware offloading")
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The only slightly tricky merge conflict was the netdevsim because the
mutex locking fix overlapped a lot of driver reload reorganization.
The rest were (relatively) trivial in nature.
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 4011921137 ("net: sched: refactor block offloads counter
usage") missed the fact that either new prog or old prog may be
NULL.
Fixes: 4011921137 ("net: sched: refactor block offloads counter usage")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull RCU and LKMM changes from Paul E. McKenney:
- Documentation updates.
- Miscellaneous fixes.
- Dynamic tick (nohz) updates, perhaps most notably changes to
force the tick on when needed due to lengthy in-kernel execution
on CPUs on which RCU is waiting.
- Replace rcu_swap_protected() with rcu_prepace_pointer().
- Torture-test updates.
- Linux-kernel memory consistency model updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Extend struct tc_action with new "tcfa_flags" field. Set the field in
tcf_idr_create() function and provide new helper
tcf_idr_create_from_flags() that derives 'cpustats' boolean from flags
value. Update individual hardware-offloaded actions init() to pass their
"flags" argument to new helper in order to skip percpu stats allocation
when user requested it through flags.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Extend TCA_ACT space with nla_bitfield32 flags. Add
TCA_ACT_FLAGS_NO_PERCPU_STATS as the only allowed flag. Parse the flags in
tcf_action_init_1() and pass resulting value as additional argument to
a_o->init().
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Modify stats update helper functions introduced in previous patches in this
series to fallback to regular tc_action->tcfa_{b|q}stats if cpu stats are
not allocated for the action argument. If regular non-percpu allocated
counters are in use, then obtain action tcfa_lock while modifying them.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Previous commit introduced helper function for updating qstats and
refactored set of actions to use the helpers, instead of modifying qstats
directly. However, one of the affected action exposes its qstats to
skb_tc_reinsert(), which then modifies it.
Refactor skb_tc_reinsert() to return integer error code and don't increment
overlimit qstats in case of error, and use the returned error code in
tcf_mirred_act() to manually increment the overlimit counter with new
helper function.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Extract common code that increments cpu_qstats counters into standalone act
API functions. Change hardware offloaded actions that use percpu counter
allocation to use the new functions instead of accessing cpu_qstats
directly.
This commit doesn't change functionality.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Extract common code that increments cpu_bstats counter into standalone act
API function. Change hardware offloaded actions that use percpu counter
allocation to use the new function instead of incrementing cpu_bstats
directly.
This commit doesn't change functionality.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, all implementations of tc_action_ops->stats_update() callback
have almost exactly the same implementation of counters update
code (besides gact which also updates drop counter). In order to simplify
support for using both percpu-allocated and regular action counters
depending on run-time flag in following patches, extract action counters
update code into standalone function in act API.
This commit doesn't change functionality.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit replaces the use of rcu_swap_protected() with the more
intuitively appealing rcu_replace_pointer() as a step towards removing
rcu_swap_protected().
Link: https://lore.kernel.org/lkml/CAHk-=wiAsJLw1egFEE=Z7-GGtM6wcvtyytXZA1+BHqta4gg6Hw@mail.gmail.com/
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
[ paulmck: From rcu_replace() to rcu_replace_pointer() per Ingo Molnar. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: <netdev@vger.kernel.org>
Cc: <linux-kernel@vger.kernel.org>
There is networking hardware that isn't based on Ethernet for layers 1 and 2.
For example CAN.
CAN is a multi-master serial bus standard for connecting Electronic Control
Units [ECUs] also known as nodes. A frame on the CAN bus carries up to 8 bytes
of payload. Frame corruption is detected by a CRC. However frame loss due to
corruption is possible, but a quite unusual phenomenon.
While fq_codel works great for TCP/IP, it doesn't for CAN. There are a lot of
legacy protocols on top of CAN, which are not build with flow control or high
CAN frame drop rates in mind.
When using fq_codel, as soon as the queue reaches a certain delay based length,
skbs from the head of the queue are silently dropped. Silently meaning that the
user space using a send() or similar syscall doesn't get an error. However
TCP's flow control algorithm will detect dropped packages and adjust the
bandwidth accordingly.
When using fq_codel and sending raw frames over CAN, which is the common use
case, the user space thinks the package has been sent without problems, because
send() returned without an error. pfifo_fast will drop skbs, if the queue
length exceeds the maximum. But with this scheduler the skbs at the tail are
dropped, an error (-ENOBUFS) is propagated to user space. So that the user
space can slow down the package generation.
On distributions, where fq_codel is made default via CONFIG_DEFAULT_NET_SCH
during compile time, or set default during runtime with sysctl
net.core.default_qdisc (see [1]), we get a bad user experience. In my test case
with pfifo_fast, I can transfer thousands of million CAN frames without a frame
drop. On the other hand with fq_codel there is more then one lost CAN frame per
thousand frames.
As pointed out fq_codel is not suited for CAN hardware, so this patch changes
attach_one_default_qdisc() to use pfifo_fast for "ARPHRD_CAN" network devices.
During transition of a netdev from down to up state the default queuing
discipline is attached by attach_default_qdiscs() with the help of
attach_one_default_qdisc(). This patch modifies attach_one_default_qdisc() to
attach the pfifo_fast (pfifo_fast_ops) if the network device type is
"ARPHRD_CAN".
[1] https://github.com/systemd/systemd/issues/9194
Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Vincent Prince <vincent.prince.fr@gmail.com>
Acked-by: Dave Taht <dave.taht@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is networking hardware that isn't based on Ethernet for layers 1 and 2.
For example CAN.
CAN is a multi-master serial bus standard for connecting Electronic Control
Units [ECUs] also known as nodes. A frame on the CAN bus carries up to 8 bytes
of payload. Frame corruption is detected by a CRC. However frame loss due to
corruption is possible, but a quite unusual phenomenon.
While fq_codel works great for TCP/IP, it doesn't for CAN. There are a lot of
legacy protocols on top of CAN, which are not build with flow control or high
CAN frame drop rates in mind.
When using fq_codel, as soon as the queue reaches a certain delay based length,
skbs from the head of the queue are silently dropped. Silently meaning that the
user space using a send() or similar syscall doesn't get an error. However
TCP's flow control algorithm will detect dropped packages and adjust the
bandwidth accordingly.
When using fq_codel and sending raw frames over CAN, which is the common use
case, the user space thinks the package has been sent without problems, because
send() returned without an error. pfifo_fast will drop skbs, if the queue
length exceeds the maximum. But with this scheduler the skbs at the tail are
dropped, an error (-ENOBUFS) is propagated to user space. So that the user
space can slow down the package generation.
On distributions, where fq_codel is made default via CONFIG_DEFAULT_NET_SCH
during compile time, or set default during runtime with sysctl
net.core.default_qdisc (see [1]), we get a bad user experience. In my test case
with pfifo_fast, I can transfer thousands of million CAN frames without a frame
drop. On the other hand with fq_codel there is more then one lost CAN frame per
thousand frames.
As pointed out fq_codel is not suited for CAN hardware, so this patch changes
attach_one_default_qdisc() to use pfifo_fast for "ARPHRD_CAN" network devices.
During transition of a netdev from down to up state the default queuing
discipline is attached by attach_default_qdiscs() with the help of
attach_one_default_qdisc(). This patch modifies attach_one_default_qdisc() to
attach the pfifo_fast (pfifo_fast_ops) if the network device type is
"ARPHRD_CAN".
[1] https://github.com/systemd/systemd/issues/9194
Signed-off-by: Vincent Prince <vincent.prince.fr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some interface types could be nested.
(VLAN, BONDING, TEAM, MACSEC, MACVLAN, IPVLAN, VIRT_WIFI, VXLAN, etc..)
These interface types should set lockdep class because, without lockdep
class key, lockdep always warn about unexisting circular locking.
In the current code, these interfaces have their own lockdep class keys and
these manage itself. So that there are so many duplicate code around the
/driver/net and /net/.
This patch adds new generic lockdep keys and some helper functions for it.
This patch does below changes.
a) Add lockdep class keys in struct net_device
- qdisc_running, xmit, addr_list, qdisc_busylock
- these keys are used as dynamic lockdep key.
b) When net_device is being allocated, lockdep keys are registered.
- alloc_netdev_mqs()
c) When net_device is being free'd llockdep keys are unregistered.
- free_netdev()
d) Add generic lockdep key helper function
- netdev_register_lockdep_key()
- netdev_unregister_lockdep_key()
- netdev_update_lockdep_key()
e) Remove unnecessary generic lockdep macro and functions
f) Remove unnecessary lockdep code of each interfaces.
After this patch, each interface modules don't need to maintain
their lockdep keys.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
UDP IPv6 packets auto flowlabels are using a 32bit secret
(static u32 hashrnd in net/core/flow_dissector.c) and
apply jhash() over fields known by the receivers.
Attackers can easily infer the 32bit secret and use this information
to identify a device and/or user, since this 32bit secret is only
set at boot time.
Really, using jhash() to generate cookies sent on the wire
is a serious security concern.
Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be
a dead end. Trying to periodically change the secret (like in sch_sfq.c)
could change paths taken in the network for long lived flows.
Let's switch to siphash, as we did in commit df453700e8
("inet: switch IP ID generator to siphash")
Using a cryptographically strong pseudo random function will solve this
privacy issue and more generally remove other weak points in the stack.
Packet schedulers using skb_get_hash_perturb() benefit from this change.
Fixes: b56774163f ("ipv6: Enable auto flow labels by default")
Fixes: 42240901f7 ("ipv6: Implement different admin modes for automatic flow labels")
Fixes: 67800f9b1f ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel")
Fixes: cb1ce2ef38 ("ipv6: Implement automatic flow label generation on transmit")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jonathan Berger <jonathann1@walla.com>
Reported-by: Amit Klein <aksecurity@gmail.com>
Reported-by: Benny Pinkas <benny@pinkas.net>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit 342db22182 ("sched: Call skb_get_hash_perturb
in sch_fq_codel") we no longer need anything from this file.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
We get one warnings when build kernel W=1:
net/sched/sch_taprio.c:1155:6: warning: no previous prototype for ‘taprio_offload_config_changed’ [-Wmissing-prototypes]
Make the function static to fix this.
Fixes: 9c66d15646 ("taprio: Add support for hardware offloading")
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Use tcf_tm_dump(), instead of an open coded variant (no functional change
in this patch).
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If packet corruption failed we jump to finish_segs and return
NET_XMIT_SUCCESS. Seeing success will make the parent qdisc
increment its backlog, that's incorrect - we need to return
NET_XMIT_DROP.
Fixes: 6071bd1aa1 ("netem: Segment GSO packets on enqueue")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To corrupt a GSO frame we first perform segmentation. We then
proceed using the first segment instead of the full GSO skb and
requeue the rest of the segments as separate packets.
If there are any issues with processing the first segment we
still want to process the rest, therefore we jump to the
finish_segs label.
Commit 177b800746 ("net: netem: fix backlog accounting for
corrupted GSO frames") started using the pointer to the first
segment in the "rest of segments processing", but as mentioned
above the first segment may had already been freed at this point.
Backlog corrections for parent qdiscs have to be adjusted.
Fixes: 177b800746 ("net: netem: fix backlog accounting for corrupted GSO frames")
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With threaded interrupts enabled, the interrupt thread runs as SCHED_RR
with priority 50. If a user application with a higher priority preempts
the interrupt thread and tries to shutdown the network interface then it
will loop forever. The kernel will spin in the loop waiting for the
device to become idle and the scheduler will never consider the
interrupt thread because its priority is lower.
Avoid the problem by sleeping for a jiffy giving other tasks,
including the interrupt thread, a chance to run and make progress.
In the original thread it has been suggested to use wait_event() and
properly waiting for the state to occur. DaveM explained that this would
require to add expensive checks in the fast paths of packet processing.
Link: https://lkml.kernel.org/r/1393976987-23555-1-git-send-email-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
[bigeasy: Rewrite commit message, add comment, use
schedule_timeout_uninterruptible()]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a application sends many packets with the same txtime, they may
be transmitted out of order (different from the order in which they
were enqueued).
This happens because when inserting elements into the tree, when the
txtime of two packets are the same, the new packet is inserted at the
left side of the tree, causing the reordering. The only effect of this
change should be that packets with the same txtime will be transmitted
in the order they are enqueued.
The application in question (the AVTP GStreamer plugin, still in
development) is sending video traffic, in which each video frame have
a single presentation time, the problem is that when packetizing,
multiple packets end up with the same txtime.
The receiving side was rejecting packets because they were being
received out of order.
Fixes: 25db26a913 ("net/sched: Introduce the ETF Qdisc")
Reported-by: Ederson de Souza <ederson.desouza@intel.com>
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit eeb84aa0d0 ("net_sched: sch_fq: do not assume EDT
packets are ordered"), all skbs get a non zero time_to_send
in flow_queue_add()
This means @time_next_packet variable in fq_dequeue()
can no longer be zero.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
the following script:
# tc qdisc add dev eth0 clsact
# tc filter add dev eth0 egress protocol ip matchall \
> action mpls push protocol mpls_uc label 0x355aa bos 1
causes corruption of all IP packets transmitted by eth0. On TC egress, we
can't rely on the value of skb->mac_len, because it's 0 and a MPLS 'push'
operation will result in an overwrite of the first 4 octets in the packet
L2 header (e.g. the Destination Address if eth0 is an Ethernet); the same
error pattern is present also in the MPLS 'pop' operation. Fix this error
in act_mpls data plane, computing 'mac_len' as the difference between the
network header and the mac header (when not at TC ingress), and use it in
MPLS 'push'/'pop' core functions.
v2: unbreak 'make htmldocs' because of missing documentation of 'mac_len'
in skb_mpls_pop(), reported by kbuild test robot
CC: Lorenzo Bianconi <lorenzo@kernel.org>
Fixes: 2a2ea50870 ("net: sched: add mpls manipulation actions to TC")
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Acked-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For the sake of tcp_poll(), there are few places where we fetch
sk->sk_wmem_queued while this field can change from IRQ or other cpu.
We need to add READ_ONCE() annotations, and also make sure write
sides use corresponding WRITE_ONCE() to avoid store-tearing.
sk_wmem_queued_add() helper is added so that we can in
the future convert to ADD_ONCE() or equivalent if/when
available.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sock_rcvlowat() or int_sk_rcvlowat() might be called without the socket
lock for example from tcp_poll().
Use READ_ONCE() to document the fact that other cpus might change
sk->sk_rcvlowat under us and avoid KCSAN splats.
Use WRITE_ONCE() on write sides too.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
If tcf_register_action failed, mirred_device_notifier
should be unregistered.
Fixes: 3b87956ea6 ("net sched: fix race in mirred device removal")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
