Pavel Begunkov says:
====================
io_uring zerocopy send
The patchset implements io_uring zerocopy send. It works with both registered
and normal buffers, mixing is allowed but not recommended. Apart from usual
request completions, just as with MSG_ZEROCOPY, io_uring separately notifies
the userspace when buffers are freed and can be reused (see API design below),
which is delivered into io_uring's Completion Queue. Those "buffer-free"
notifications are not necessarily per request, but the userspace has control
over it and should explicitly attaching a number of requests to a single
notification. The series also adds some internal optimisations when used with
registered buffers like removing page referencing.
From the kernel networking perspective there are two main changes. The first
one is passing ubuf_info into the network layer from io_uring (inside of an
in kernel struct msghdr). This allows extra optimisations, e.g. ubuf_info
caching on the io_uring side, but also helps to avoid cross-referencing
and synchronisation problems. The second part is an optional optimisation
removing page referencing for requests with registered buffers.
Benchmarking UDP with an optimised version of the selftest (see [1]), which
sends a bunch of requests, waits for completions and repeats. "+ flush" column
posts one additional "buffer-free" notification per request, and just "zc"
doesn't post buffer notifications at all.
NIC (requests / second):
IO size | non-zc | zc | zc + flush
4000 | 495134 | 606420 (+22%) | 558971 (+12%)
1500 | 551808 | 577116 (+4.5%) | 565803 (+2.5%)
1000 | 584677 | 592088 (+1.2%) | 560885 (-4%)
600 | 596292 | 598550 (+0.4%) | 555366 (-6.7%)
dummy (requests / second):
IO size | non-zc | zc | zc + flush
8000 | 1299916 | 2396600 (+84%) | 2224219 (+71%)
4000 | 1869230 | 2344146 (+25%) | 2170069 (+16%)
1200 | 2071617 | 2361960 (+14%) | 2203052 (+6%)
600 | 2106794 | 2381527 (+13%) | 2195295 (+4%)
Previously it also brought a massive performance speedup compared to the
msg_zerocopy tool (see [3]), which is probably not super interesting. There
is also an additional bunch of refcounting optimisations that was omitted from
the series for simplicity and as they don't change the picture drastically,
they will be sent as follow up, as well as flushing optimisations closing the
performance gap b/w two last columns.
For TCP on localhost (with hacks enabling localhost zerocopy) and including
additional overhead for receive:
IO size | non-zc | zc
1200 | 4174 | 4148
4096 | 7597 | 11228
Using a real NIC 1200 bytes, zc is worse than non-zc ~5-10%, maybe the
omitted optimisations will somewhat help, should look better for 4000,
but couldn't test properly because of setup problems.
Links:
liburing (benchmark + tests):
[1] https://github.com/isilence/liburing/tree/zc_v4
kernel repo:
[2] https://github.com/isilence/linux/tree/zc_v4
RFC v1:
[3] https://lore.kernel.org/io-uring/cover.1638282789.git.asml.silence@gmail.com/
RFC v2:
https://lore.kernel.org/io-uring/cover.1640029579.git.asml.silence@gmail.com/
Net patches based:
git@github.com:isilence/linux.git zc_v4-net-base
or
https://github.com/isilence/linux/tree/zc_v4-net-base
API design overview:
The series introduces an io_uring concept of notifactors. From the userspace
perspective it's an entity to which it can bind one or more requests and then
requesting to flush it. Flushing a notifier makes it impossible to attach new
requests to it, and instructs the notifier to post a completion once all
requests attached to it are completed and the kernel doesn't need the buffers
anymore.
Notifications are stored in notification slots, which should be registered as
an array in io_uring. Each slot stores only one notifier at any particular
moment. Flushing removes it from the slot and the slot automatically replaces
it with a new notifier. All operations with notifiers are done by specifying
an index of a slot it's currently in.
When registering a notification the userspace specifies a u64 tag for each
slot, which will be copied in notification completion entries as
cqe::user_data. cqe::res is 0 and cqe::flags is equal to wrap around u32
sequence number counting notifiers of a slot.
====================
Link: https://lore.kernel.org/r/cover.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Teach ipv6/udp how to use external ubuf_info provided in msghdr and
also prepare it for managed frags by sprinkling
skb_zcopy_downgrade_managed() when it could mix managed and not managed
frags.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Even when zerocopy transmission is requested and possible,
__ip_append_data() will still copy a small chunk of data just because it
allocated some extra linear space (e.g. 128 bytes). It wastes CPU cycles
on copy and iter manipulations and also misalignes potentially aligned
data. Avoid such copies. And as a bonus we can allocate smaller skb.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
While reading sysctl_tcp_syncookies, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a third knob, '2', which extends the
accept_untracked_na option to learn a neighbor only if the src ip is
in the same subnet as an address configured on the interface that
received the neighbor advertisement. This is similar to the arp_accept
configuration for ipv4.
Signed-off-by: Jaehee Park <jhpark1013@gmail.com>
Suggested-by: Roopa Prabhu <roopa@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit e21145a987 ("ipv4: namespacify ip_early_demux sysctl knob") made
it possible to enable/disable early_demux on a per-netns basis. Then, we
introduced two knobs, tcp_early_demux and udp_early_demux, to switch it for
TCP/UDP in commit dddb64bcb3 ("net: Add sysctl to toggle early demux for
tcp and udp"). However, the .proc_handler() was wrong and actually
disabled us from changing the behaviour in each netns.
We can execute early_demux if net.ipv4.ip_early_demux is on and each proto
.early_demux() handler is not NULL. When we toggle (tcp|udp)_early_demux,
the change itself is saved in each netns variable, but the .early_demux()
handler is a global variable, so the handler is switched based on the
init_net's sysctl variable. Thus, netns (tcp|udp)_early_demux knobs have
nothing to do with the logic. Whether we CAN execute proto .early_demux()
is always decided by init_net's sysctl knob, and whether we DO it or not is
by each netns ip_early_demux knob.
This patch namespacifies (tcp|udp)_early_demux again. For now, the users
of the .early_demux() handler are TCP and UDP only, and they are called
directly to avoid retpoline. So, we can remove the .early_demux() handler
from inet6?_protos and need not dereference them in ip6?_rcv_finish_core().
If another proto needs .early_demux(), we can restore it at that time.
Fixes: dddb64bcb3 ("net: Add sysctl to toggle early demux for tcp and udp")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20220713175207.7727-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
While reading sysctl_ip_no_pmtu_disc, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The SRv6 End.B6 and End.B6.Encaps behaviors rely on functions
seg6_do_srh_{encap,inline}() to, respectively: i) encapsulate the
packet within an outer IPv6 header with the specified Segment Routing
Header (SRH); ii) insert the specified SRH directly after the IPv6
header of the packet.
This patch removes the initialization of the IPv6 header payload length
from the input_action_end_b6{_encap}() functions, as it is now handled
properly by seg6_do_srh_{encap,inline}() to avoid corruption of the skb
checksum.
Fixes: 140f04c33b ("ipv6: sr: implement several seg6local actions")
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Support for SRH encapsulation and insertion was introduced with
commit 6c8702c60b ("ipv6: sr: add support for SRH encapsulation and
injection with lwtunnels"), through the seg6_do_srh_encap() and
seg6_do_srh_inline() functions, respectively.
The former encapsulates the packet in an outer IPv6 header along with
the SRH, while the latter inserts the SRH between the IPv6 header and
the payload. Then, the headers are initialized/updated according to the
operating mode (i.e., encap/inline).
Finally, the skb checksum is calculated to reflect the changes applied
to the headers.
The IPv6 payload length ('payload_len') is not initialized
within seg6_do_srh_{inline,encap}() but is deferred in seg6_do_srh(), i.e.
the caller of seg6_do_srh_{inline,encap}().
However, this operation invalidates the skb checksum, since the
'payload_len' is updated only after the checksum is evaluated.
To solve this issue, the initialization of the IPv6 payload length is
moved from seg6_do_srh() directly into the seg6_do_srh_{inline,encap}()
functions and before the skb checksum update takes place.
Fixes: 6c8702c60b ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Reported-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/all/20220705190727.69d532417be7438b15404ee1@uniroma2.it
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The IPv6 multicast routing code previously implemented only the dump
variant of RTM_GETROUTE. Implement single MFC item retrieval by copying
and adapting the respective IPv4 code.
Tested against FRRouting's IPv6 PIM stack.
Signed-off-by: David Lamparter <equinox@diac24.net>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Cc: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
While reading nexthop_compat_mode, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.
Fixes: 4f80116d3d ("net: ipv4: add sysctl for nexthop api compatibility mode")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While reading sysctl_icmp_echo_enable_probe, it can be changed
concurrently. Thus, we need to add READ_ONCE() to its readers.
Fixes: d329ea5bd8 ("icmp: add response to RFC 8335 PROBE messages")
Fixes: 1fd07f33c3 ("ipv6: ICMPV6: add response to ICMPV6 RFC 8335 PROBE messages")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current code allows to inherit the TTL (hop_limit) from the
payload when skb->protocol is ETH_P_IP or ETH_P_IPV6.
However when the payload is VLAN encapsulated (e.g because the tunnel
is of type GRETAP), then this inheriting does not work, because the
visible skb->protocol is of type ETH_P_8021Q or ETH_P_8021AD.
Instead of skb->protocol, use skb_protocol().
Signed-off-by: Matthias May <matthias.may@westermo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the payload is a VLAN encapsulated IPv6/IPv6 frame, we can
skip the 802.1q/802.1ad ethertypes and jump to the actual protocol.
This way we treat IPv4/IPv6 frames as IP instead of as "other".
Signed-off-by: Matthias May <matthias.may@westermo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current code always forces a dscp of 0 for all non-IP frames.
However when setting a specific TOS with the command
ip link add name tep0 type ip6gretap local fdd1:ced0:5d88:3fce::1
remote fdd1:ced0:5d88:3fce::2 tos 0xa0
one would expect all GRE encapsulated frames to have a TOS of 0xA0.
and not only when the payload is IPv4/IPv6.
Signed-off-by: Matthias May <matthias.may@westermo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If we set XFRM security policy by calling setsockopt with option
IPV6_XFRM_POLICY, the policy will be stored in 'sock_policy' in 'sock'
struct. However tcp_v6_send_response doesn't look up dst_entry with the
actual socket but looks up with tcp control socket. This may cause a
problem that a RST packet is sent without ESP encryption & peer's TCP
socket can't receive it.
This patch will make the function look up dest_entry with actual socket,
if the socket has XFRM policy(sock_policy), so that the TCP response
packet via this function can be encrypted, & aligned on the encrypted
TCP socket.
Tested: We encountered this problem when a TCP socket which is encrypted
in ESP transport mode encryption, receives challenge ACK at SYN_SENT
state. After receiving challenge ACK, TCP needs to send RST to
establish the socket at next SYN try. But the RST was not encrypted &
peer TCP socket still remains on ESTABLISHED state.
So we verified this with test step as below.
[Test step]
1. Making a TCP state mismatch between client(IDLE) & server(ESTABLISHED).
2. Client tries a new connection on the same TCP ports(src & dst).
3. Server will return challenge ACK instead of SYN,ACK.
4. Client will send RST to server to clear the SOCKET.
5. Client will retransmit SYN to server on the same TCP ports.
[Expected result]
The TCP connection should be established.
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Sehee Lee <seheele@google.com>
Signed-off-by: Sewook Seo <sewookseo@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf-next 2022-07-09
We've added 94 non-merge commits during the last 19 day(s) which contain
a total of 125 files changed, 5141 insertions(+), 6701 deletions(-).
The main changes are:
1) Add new way for performing BTF type queries to BPF, from Daniel Müller.
2) Add inlining of calls to bpf_loop() helper when its function callback is
statically known, from Eduard Zingerman.
3) Implement BPF TCP CC framework usability improvements, from Jörn-Thorben Hinz.
4) Add LSM flavor for attaching per-cgroup BPF programs to existing LSM
hooks, from Stanislav Fomichev.
5) Remove all deprecated libbpf APIs in prep for 1.0 release, from Andrii Nakryiko.
6) Add benchmarks around local_storage to BPF selftests, from Dave Marchevsky.
7) AF_XDP sample removal (given move to libxdp) and various improvements around AF_XDP
selftests, from Magnus Karlsson & Maciej Fijalkowski.
8) Add bpftool improvements for memcg probing and bash completion, from Quentin Monnet.
9) Add arm64 JIT support for BPF-2-BPF coupled with tail calls, from Jakub Sitnicki.
10) Sockmap optimizations around throughput of UDP transmissions which have been
improved by 61%, from Cong Wang.
11) Rework perf's BPF prologue code to remove deprecated functions, from Jiri Olsa.
12) Fix sockmap teardown path to avoid sleepable sk_psock_stop, from John Fastabend.
13) Fix libbpf's cleanup around legacy kprobe/uprobe on error case, from Chuang Wang.
14) Fix libbpf's bpf_helpers.h to work with gcc for the case of its sec/pragma
macro, from James Hilliard.
15) Fix libbpf's pt_regs macros for riscv to use a0 for RC register, from Yixun Lan.
16) Fix bpftool to show the name of type BPF_OBJ_LINK, from Yafang Shao.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (94 commits)
selftests/bpf: Fix xdp_synproxy build failure if CONFIG_NF_CONNTRACK=m/n
bpf: Correctly propagate errors up from bpf_core_composites_match
libbpf: Disable SEC pragma macro on GCC
bpf: Check attach_func_proto more carefully in check_return_code
selftests/bpf: Add test involving restrict type qualifier
bpftool: Add support for KIND_RESTRICT to gen min_core_btf command
MAINTAINERS: Add entry for AF_XDP selftests files
selftests, xsk: Rename AF_XDP testing app
bpf, docs: Remove deprecated xsk libbpf APIs description
selftests/bpf: Add benchmark for local_storage RCU Tasks Trace usage
libbpf, riscv: Use a0 for RC register
libbpf: Remove unnecessary usdt_rel_ip assignments
selftests/bpf: Fix few more compiler warnings
selftests/bpf: Fix bogus uninitialized variable warning
bpftool: Remove zlib feature test from Makefile
libbpf: Cleanup the legacy uprobe_event on failed add/attach_event()
libbpf: Fix wrong variable used in perf_event_uprobe_open_legacy()
libbpf: Cleanup the legacy kprobe_event on failed add/attach_event()
selftests/bpf: Add type match test against kernel's task_struct
selftests/bpf: Add nested type to type based tests
...
====================
Link: https://lore.kernel.org/r/20220708233145.32365-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
drivers/net/ethernet/microchip/sparx5/sparx5_switchdev.c
9c5de246c1 ("net: sparx5: mdb add/del handle non-sparx5 devices")
fbb89d02e3 ("net: sparx5: Allow mdb entries to both CPU and ports")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
commit ed6cd6a178 ("net, neigh: Set lower cap for neigh_managed_work rearming")
fixed a case when DELAY_PROBE_TIME is configured to 0, the processing of the
system work queue hog CPU to 100%, and further more we should introduce
a new option used by periodic probe
Signed-off-by: Yuwei Wang <wangyuweihx@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
There is no need to store the result of the addition back to variable count
after the addition. The store is redundant, replace += with just +
Cleans up clang scan build warning:
warning: Although the value stored to 'count' is used in the enclosing
expression, the value is never actually read from 'count'
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220628145406.183527-1-colin.i.king@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
As of commit 5801f064e3 ("net: ipv6: unexport __init-annotated seg6_hmac_init()"),
EXPORT_SYMBOL and __init is a bad combination because the .init.text
section is freed up after the initialization. Hence, modules cannot
use symbols annotated __init. The access to a freed symbol may end up
with kernel panic.
This remove the EXPORT_SYMBOL to fix modpost warning:
WARNING: modpost: vmlinux.o(___ksymtab+seg6_hmac_net_init+0x0): Section mismatch in reference from the variable __ksymtab_seg6_hmac_net_init to the function .init.text:seg6_hmac_net_init()
The symbol seg6_hmac_net_init is exported and annotated __init
Fix this by removing the __init annotation of seg6_hmac_net_init or drop the export.
Fixes: bf355b8d2c ("ipv6: sr: add core files for SR HMAC support")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20220628033134.21088-1-yuehaibing@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When kcalloc fails, ipip6_tunnel_get_prl() should return -ENOMEM.
Move the position of label "out" to return correctly.
Addresses-Coverity: ("Unused value")
Fixes: 300aaeeaab ("[IPV6] SIT: Add SIOCGETPRL ioctl to get/dump PRL.")
Signed-off-by: katrinzhou <katrinzhou@tencent.com>
Reviewed-by: Eric Dumazet<edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220628035030.1039171-1-zys.zljxml@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The addrconf_verify_rtnl() function uses a big if/elseif/elseif/... block
to categorize each address by what type of attention it needs. An
about-to-expire (RFC 4941) temporary address is one such category, but the
previous elseif branch catches addresses that have already run out their
prefered_lft. This means that if addrconf_verify_rtnl() fails to run in
the necessary time window (i.e. REGEN_ADVANCE time units before the end of
the prefered_lft), the temporary address will never be regenerated, and no
temporary addresses will be available until each one's valid_lft runs out
and manage_tempaddrs() begins anew.
Fix this by moving the entire temporary address regeneration case out of
that block. That block is supposed to implement the "destructive" part of
an address's lifecycle, and regenerating a fresh temporary address is not,
semantically speaking, actually tied to any particular lifecycle stage.
The age test is also changed from `age >= prefered_lft - regen_advance`
to `age + regen_advance >= prefered_lft` instead, to ensure no underflow
occurs if the system administrator increases the regen_advance to a value
greater than the already-set prefered_lft.
Note that this does not fix the problem of addrconf_verify_rtnl() sometimes
not running in time, resulting in the race condition described in RFC 4941
section 3.4 - it only ensures that the address is regenerated. Fixing THAT
problem may require either using jiffies instead of seconds for all time
arithmetic here, or always rounding up when regen_advance is converted to
seconds.
Signed-off-by: Sam Edwards <CFSworks@gmail.com>
Link: https://lore.kernel.org/r/20220623181103.7033-1-CFSworks@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When routes corresponding to addresses are restored by
fixup_permanent_addr(), the dst_nopolicy parameter was not set.
The typical use case is a user that configures an address on a down
interface and then put this interface up.
Let's take care of this flag in addrconf_f6i_alloc(), so that every callers
benefit ont it.
CC: stable@kernel.org
CC: David Forster <dforster@brocade.com>
Fixes: df789fe752 ("ipv6: Provide ipv6 version of "disable_policy" sysctl")
Reported-by: Siwar Zitouni <siwar.zitouni@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220623120015.32640-1-nicolas.dichtel@6wind.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mrt_lock is only held in write mode, from process context only.
We can switch to a mere spinlock, and avoid blocking BH.
Also, vif_dev_read() is always called under standard rcu_read_lock().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We can use standard rcu_read_lock(), to get rid
of last read_lock(&mrt_lock) call points.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We no longer need to acquire mrt_lock() in mr_dump,
using rcu_read_lock() is enough.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Like ipmr_get_route(), we can use standard RCU here.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ip6_mr_forward() uses standard RCU protection already.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rcu_read_lock() protection is good enough.
ip6mr_cache_unresolved() uses a dedicated spinlock (mfc_unres_lock)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rcu_read_lock() protection is more than enough.
vif_dev_read() supports either mrt_lock or rcu_read_lock().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ip6mr_cache_report() first argument can be marked const, and we change
the caller convention about which lock needs to be held.
Instead of read_lock(&mrt_lock), we can use rcu_read_lock().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We will soon use RCU instead of rwlock in ipmr & ip6mr
This preliminary patch adds proper rcu verbs to read/write
(struct vif_device)->dev
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
pim6_rcv() is called under rcu_read_lock(), there is
no need to use dev_hold()/dev_put() pair.
IPv4 side was handled in commit 55747a0a73
("ipmr: __pim_rcv() is called under rcu_read_lock")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
saddr and daddr are set but not used.
Fixes: ba44f8182e ("raw: use more conventional iterators")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Link: https://lore.kernel.org/r/20220622032303.159394-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Currently both splice() and sockmap use ->read_sock() to
read skb from receive queue, but for sockmap we only read
one entire skb at a time, so ->read_sock() is too conservative
to use. Introduce a new proto_ops ->read_skb() which supports
this sematic, with this we can finally pass the ownership of
skb to recv actors.
For non-TCP protocols, all ->read_sock() can be simply
converted to ->read_skb().
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220615162014.89193-3-xiyou.wangcong@gmail.com
hlist_nulls_add_head_rcu() and hlist_nulls_for_each_entry() have dedicated
macros for sk.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using rwlock in networking code is extremely risky.
writers can starve if enough readers are constantly
grabing the rwlock.
I thought rwlock were at fault and sent this patch:
https://lkml.org/lkml/2022/6/17/272
But Peter and Linus essentially told me rwlock had to be unfair.
We need to get rid of rwlock in networking code.
Without this fix, following script triggers soft lockups:
for i in {1..48}
do
ping -f -n -q 127.0.0.1 &
sleep 0.1
done
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to prepare the following patch,
I change raw v4 & v6 code to use more conventional
iterators.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Each protocol having a ->memory_allocated pointer gets a corresponding
per-cpu reserve, that following patches will use.
Instead of having reserved bytes per socket,
we want to have per-cpu reserves.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit 40867d74c3 ("net: Add l3mdev index to flow struct and avoid oif
reset for port devices") adds a new entry (flowi_l3mdev) in the common
flow struct used for indicating the l3mdev index for later rule and
table matching.
The l3mdev_update_flow() has been adapted to properly set the
flowi_l3mdev based on the flowi_oif/flowi_iif. In fact, when a valid
flowi_iif is supplied to the l3mdev_update_flow(), this function can
update the flowi_l3mdev entry only if it has not yet been set (i.e., the
flowi_l3mdev entry is equal to 0).
The SRv6 End.DT6 behavior in VRF mode leverages a VRF device in order to
force the routing lookup into the associated routing table. This routing
operation is performed by seg6_lookup_any_nextop() preparing a flowi6
data structure used by ip6_route_input_lookup() which, in turn,
(indirectly) invokes l3mdev_update_flow().
However, seg6_lookup_any_nexthop() does not initialize the new
flowi_l3mdev entry which is filled with random garbage data. This
prevents l3mdev_update_flow() from properly updating the flowi_l3mdev
with the VRF index, and thus SRv6 End.DT6 (VRF mode)/DT46 behaviors are
broken.
This patch correctly initializes the flowi6 instance allocated and used
by seg6_lookup_any_nexhtop(). Specifically, the entire flowi6 instance
is wiped out: in case new entries are added to flowi/flowi6 (as happened
with the flowi_l3mdev entry), we should no longer have incorrectly
initialized values. As a result of this operation, the value of
flowi_l3mdev is also set to 0.
The proposed fix can be tested easily. Starting from the commit
referenced in the Fixes, selftests [1],[2] indicate that the SRv6
End.DT6 (VRF mode)/DT46 behaviors no longer work correctly. By applying
this patch, those behaviors are back to work properly again.
[1] - tools/testing/selftests/net/srv6_end_dt46_l3vpn_test.sh
[2] - tools/testing/selftests/net/srv6_end_dt6_l3vpn_test.sh
Fixes: 40867d74c3 ("net: Add l3mdev index to flow struct and avoid oif reset for port devices")
Reported-by: Anton Makarov <am@3a-alliance.com>
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220608091917.20345-1-andrea.mayer@uniroma2.it
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
