Commit Graph

1144 Commits

Author SHA1 Message Date
Eric Dumazet
d45cf1e7d7 ipv6: reject malicious packets in ipv6_gso_segment()
syzbot was able to craft a packet with very long IPv6 extension headers
leading to an overflow of skb->transport_header.

This 16bit field has a limited range.

Add skb_reset_transport_header_careful() helper and use it
from ipv6_gso_segment()

WARNING: CPU: 0 PID: 5871 at ./include/linux/skbuff.h:3032 skb_reset_transport_header include/linux/skbuff.h:3032 [inline]
WARNING: CPU: 0 PID: 5871 at ./include/linux/skbuff.h:3032 ipv6_gso_segment+0x15e2/0x21e0 net/ipv6/ip6_offload.c:151
Modules linked in:
CPU: 0 UID: 0 PID: 5871 Comm: syz-executor211 Not tainted 6.16.0-rc6-syzkaller-g7abc678e3084 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
 RIP: 0010:skb_reset_transport_header include/linux/skbuff.h:3032 [inline]
 RIP: 0010:ipv6_gso_segment+0x15e2/0x21e0 net/ipv6/ip6_offload.c:151
Call Trace:
 <TASK>
  skb_mac_gso_segment+0x31c/0x640 net/core/gso.c:53
  nsh_gso_segment+0x54a/0xe10 net/nsh/nsh.c:110
  skb_mac_gso_segment+0x31c/0x640 net/core/gso.c:53
  __skb_gso_segment+0x342/0x510 net/core/gso.c:124
  skb_gso_segment include/net/gso.h:83 [inline]
  validate_xmit_skb+0x857/0x11b0 net/core/dev.c:3950
  validate_xmit_skb_list+0x84/0x120 net/core/dev.c:4000
  sch_direct_xmit+0xd3/0x4b0 net/sched/sch_generic.c:329
  __dev_xmit_skb net/core/dev.c:4102 [inline]
  __dev_queue_xmit+0x17b6/0x3a70 net/core/dev.c:4679

Fixes: d1da932ed4 ("ipv6: Separate ipv6 offload support")
Reported-by: syzbot+af43e647fd835acc02df@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/688a1a05.050a0220.5d226.0008.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Dawid Osuchowski <dawid.osuchowski@linux.intel.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250730131738.3385939-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-01 14:40:53 -07:00
Michal Luczaj
25489a4f55 net: splice: Drop unused @gfp
Since its introduction in commit 2e910b9532 ("net: Add a function to
splice pages into an skbuff for MSG_SPLICE_PAGES"), skb_splice_from_iter()
never used the @gfp argument. Remove it and adapt callers.

No functional change intended.

Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Link: https://patch.msgid.link/20250702-splice-drop-unused-v3-2-55f68b60d2b7@rbox.co
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-08 08:37:15 -07:00
Mina Almasry
4672aec56d netmem: fix skb_frag_address_safe with unreadable skbs
skb_frag_address_safe() needs a check that the
skb_frag_page exists check similar to skb_frag_address().

Cc: ap420073@gmail.com

Signed-off-by: Mina Almasry <almasrymina@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250619175239.3039329-1-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-21 07:35:01 -07:00
Dragos Tatulea
1cbb49f85b net: Add skb_can_coalesce for netmem
Allow drivers that have moved over to netmem to do fragment coalescing.

Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Link: https://patch.msgid.link/20250616141441.1243044-3-mbloch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-17 18:34:11 -07:00
Eric Biggers
c93f75b2d7 net: remove skb_copy_and_hash_datagram_iter()
Now that skb_copy_and_hash_datagram_iter() is no longer used, remove it.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://patch.msgid.link/20250519175012.36581-11-ebiggers@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-21 15:40:17 -07:00
Eric Biggers
ea6342d989 net: add skb_copy_and_crc32c_datagram_iter()
Since skb_copy_and_hash_datagram_iter() is used only with CRC32C, the
crypto_ahash abstraction provides no value.  Add
skb_copy_and_crc32c_datagram_iter() which just calls crc32c() directly.

This is faster and simpler.  It also doesn't have the weird dependency
issue where skb_copy_and_hash_datagram_iter() depends on
CONFIG_CRYPTO_HASH=y without that being expressed explicitly in the
kconfig (presumably because it was too heavyweight for NET to select).
The new function is conditional on the hidden boolean symbol NET_CRC32C,
which selects CRC32.  So it gets compiled only when something that
actually needs CRC32C packet checksums is enabled, it has no implicit
dependency, and it doesn't depend on the heavyweight crypto layer.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://patch.msgid.link/20250519175012.36581-9-ebiggers@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-21 15:40:17 -07:00
Eric Biggers
70c96c7cb9 net: fold __skb_checksum() into skb_checksum()
Now that the only remaining caller of __skb_checksum() is
skb_checksum(), fold __skb_checksum() into skb_checksum().  This makes
struct skb_checksum_ops unnecessary, so remove that too and simply do
the "regular" net checksum.  It also makes the wrapper functions
csum_partial_ext() and csum_block_add_ext() unnecessary, so remove those
too and just use the underlying functions.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://patch.msgid.link/20250519175012.36581-7-ebiggers@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-21 15:40:16 -07:00
Eric Biggers
a5bd029c73 net: add skb_crc32c()
Add skb_crc32c(), which calculates the CRC32C of a sk_buff.  It will
replace __skb_checksum(), which unnecessarily supports arbitrary
checksums.  Compared to __skb_checksum(), skb_crc32c():

   - Uses the correct type for CRC32C values (u32, not __wsum).

   - Does not require the caller to provide a skb_checksum_ops struct.

   - Is faster because it does not use indirect calls and does not use
     the very slow crc32c_combine().

According to commit 2817a336d4 ("net: skb_checksum: allow custom
update/combine for walking skb") which added __skb_checksum(), the
original motivation for the abstraction layer was to avoid code
duplication for CRC32C and other checksums in the future.  However:

   - No additional checksums showed up after CRC32C.  __skb_checksum()
     is only used with the "regular" net checksum and CRC32C.

   - Indirect calls are expensive.  Commit 2544af0344 ("net: avoid
     indirect calls in L4 checksum calculation") worked around this
     using the INDIRECT_CALL_1 macro. But that only avoided the indirect
     call for the net checksum, and at the cost of an extra branch.

   - The checksums use different types (__wsum and u32), causing casts
     to be needed.

   - It made the checksums of fragments be combined (rather than
     chained) for both checksums, despite this being highly
     counterproductive for CRC32C due to how slow crc32c_combine() is.
     This can clearly be seen in commit 4c2f245496 ("sctp: linearize
     early if it's not GSO") which tried to work around this performance
     bug.  With a dedicated function for each checksum, we can instead
     just use the proper strategy for each checksum.

As shown by the following tables, the new function skb_crc32c() is
faster than __skb_checksum(), with the improvement varying greatly from
5% to 2500% depending on the case.  The largest improvements come from
fragmented packets, mainly due to eliminating the inefficient
crc32c_combine().  But linear packets are improved too, especially
shorter ones, mainly due to eliminating indirect calls.  These
benchmarks were done on AMD Zen 5.  On that CPU, Linux uses IBRS instead
of retpoline; an even greater improvement might be seen with retpoline:

    Linear sk_buffs

        Length in bytes    __skb_checksum cycles    skb_crc32c cycles
        ===============    =====================    =================
                     64                       43                   18
                    256                       94                   77
                   1420                      204                  161
                  16384                     1735                 1642

    Nonlinear sk_buffs (even split between head and one fragment)

        Length in bytes    __skb_checksum cycles    skb_crc32c cycles
        ===============    =====================    =================
                     64                      579                   22
                    256                      829                   77
                   1420                     1506                  194
                  16384                     4365                 1682

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://patch.msgid.link/20250519175012.36581-3-ebiggers@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-21 15:39:58 -07:00
Mina Almasry
bd61848900 net: devmem: Implement TX path
Augment dmabuf binding to be able to handle TX. Additional to all the RX
binding, we also create tx_vec needed for the TX path.

Provide API for sendmsg to be able to send dmabufs bound to this device:

- Provide a new dmabuf_tx_cmsg which includes the dmabuf to send from.
- MSG_ZEROCOPY with SCM_DEVMEM_DMABUF cmsg indicates send from dma-buf.

Devmem is uncopyable, so piggyback off the existing MSG_ZEROCOPY
implementation, while disabling instances where MSG_ZEROCOPY falls back
to copying.

We additionally pipe the binding down to the new
zerocopy_fill_skb_from_devmem which fills a TX skb with net_iov netmems
instead of the traditional page netmems.

We also special case skb_frag_dma_map to return the dma-address of these
dmabuf net_iovs instead of attempting to map pages.

The TX path may release the dmabuf in a context where we cannot wait.
This happens when the user unbinds a TX dmabuf while there are still
references to its netmems in the TX path. In that case, the netmems will
be put_netmem'd from a context where we can't unmap the dmabuf, Resolve
this by making __net_devmem_dmabuf_binding_free schedule_work'd.

Based on work by Stanislav Fomichev <sdf@fomichev.me>. A lot of the meat
of the implementation came from devmem TCP RFC v1[1], which included the
TX path, but Stan did all the rebasing on top of netmem/net_iov.

Cc: Stanislav Fomichev <sdf@fomichev.me>
Signed-off-by: Kaiyuan Zhang <kaiyuanz@google.com>
Signed-off-by: Mina Almasry <almasrymina@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250508004830.4100853-5-almasrymina@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-05-13 11:12:48 +02:00
Jakub Kicinski
9daaf19786 wireless features, notably
* stack
    - free SKBTX_WIFI_STATUS flag
    - fixes for VLAN multicast in multi-link
    - improve codel parameters (revert some old twiddling)
  * ath12k
    - Enable AHB support for IPQ5332.
    - Add monitor interface support to QCN9274.
    - Add MLO support to WCN7850.
    - Add 802.11d scan offload support to WCN7850.
  * ath11k
    - Restore hibernation support
  * iwlwifi
    - EMLSR on two 5 GHz links
  * mwifiex
    - cleanups/refactoring
 
 along with many other small features/cleanups
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Merge tag 'wireless-next-2025-05-06' of https://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next

Johannes Berg says:

====================
wireless features, notably

 * stack
   - free SKBTX_WIFI_STATUS flag
   - fixes for VLAN multicast in multi-link
   - improve codel parameters (revert some old twiddling)
 * ath12k
   - Enable AHB support for IPQ5332.
   - Add monitor interface support to QCN9274.
   - Add MLO support to WCN7850.
   - Add 802.11d scan offload support to WCN7850.
 * ath11k
   - Restore hibernation support
 * iwlwifi
   - EMLSR on two 5 GHz links
 * mwifiex
   - cleanups/refactoring

along with many other small features/cleanups

* tag 'wireless-next-2025-05-06' of https://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next: (177 commits)
  Revert "wifi: iwlwifi: clean up config macro"
  wifi: iwlwifi: move phy_filters to fw_runtime
  wifi: iwlwifi: pcie: make sure to lock rxq->read
  wifi: iwlwifi: add definitions for iwl_mac_power_cmd version 2
  wifi: iwlwifi: clean up config macro
  wifi: iwlwifi: mld: simplify iwl_mld_rx_fill_status()
  wifi: iwlwifi: mld: rx: simplify channel handling
  wifi: iwlwifi: clean up band in RX metadata
  wifi: iwlwifi: mld: skip unknown FW channel load values
  wifi: iwlwifi: define API for external FSEQ images
  wifi: iwlwifi: mld: allow EMLSR on separated 5 GHz subbands
  wifi: iwlwifi: mld: use cfg80211_chandef_get_width()
  wifi: iwlwifi: mld: fix iwl_mld_emlsr_disallowed_with_link() return
  wifi: iwlwifi: mld: clarify variable type
  wifi: iwlwifi: pcie: add support for the reset handshake in MSI
  wifi: mac80211_hwsim: Prevent tsf from setting if beacon is disabled
  wifi: mac80211: restructure tx profile retrieval for MLO MBSSID
  wifi: nl80211: add link id of transmitted profile for MLO MBSSID
  wifi: ieee80211: Add helpers to fetch EMLSR delay and timeout values
  wifi: mac80211: update ML STA with EML capabilities
  ...

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

Link: https://patch.msgid.link/20250506174656.119970-3-johannes@sipsolutions.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-06 19:04:42 -07:00
Johannes Berg
76a853f86c wifi: free SKBTX_WIFI_STATUS skb tx_flags flag
Jason mentioned at netdevconf that we've run out of tx_flags in
the skb_shinfo(). Gain one bit back by removing the wifi bit.

We can do that because the only userspace application for it
(hostapd) doesn't change the setting on the socket, it just
uses different sockets, and normally doesn't even use this any
more, sending the frames over nl80211 instead.

Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Link: https://patch.msgid.link/20250313134942.52ff54a140ec.If390bbdc46904cf451256ba989d7a056c457af6e@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2025-04-23 15:09:25 +02:00
Antonio Quartulli
17240749f2 skb: implement skb_send_sock_locked_with_flags()
When sending an skb over a socket using skb_send_sock_locked(),
it is currently not possible to specify any flag to be set in
msghdr->msg_flags.

However, we may want to pass flags the user may have specified,
like MSG_NOSIGNAL.

Extend __skb_send_sock() with a new argument 'flags' and add a
new interface named skb_send_sock_locked_with_flags().

Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <horms@kernel.org>
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
Link: https://patch.msgid.link/20250415-b4-ovpn-v26-12-577f6097b964@openvpn.net
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-04-17 12:30:03 +02:00
Michal Luczaj
420aabef3a net: Drop unused @sk of __skb_try_recv_from_queue()
__skb_try_recv_from_queue() deals with a queue, @sk is not used
since commit  e427cad6ee ("net: datagram: drop 'destructor'
argument from several helpers"). Remove sk from function parameters,
adapt callers.

No functional change intended.

Signed-off-by: Michal Luczaj <mhal@rbox.co>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Link: https://patch.msgid.link/20250407-cleanup-drop-param-sk-v1-1-cd076979afac@rbox.co
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-08 18:23:51 -07:00
Pauli Virtanen
983e0e4e87 net-timestamp: COMPLETION timestamp on packet tx completion
Add SOF_TIMESTAMPING_TX_COMPLETION, for requesting a software timestamp
when hardware reports a packet completed.

Completion tstamp is useful for Bluetooth, as hardware timestamps do not
exist in the HCI specification except for ISO packets, and the hardware
has a queue where packets may wait.  In this case the software SND
timestamp only reflects the kernel-side part of the total latency
(usually small) and queue length (usually 0 unless HW buffers
congested), whereas the completion report time is more informative of
the true latency.

It may also be useful in other cases where HW TX timestamps cannot be
obtained and user wants to estimate an upper bound to when the TX
probably happened.

Signed-off-by: Pauli Virtanen <pav@iki.fi>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2025-03-25 12:48:05 -04:00
Yue Haibing
24faa63bce net: skbuff: Remove unused skb_add_data()
Since commit a4ea4c4776 ("rxrpc: Don't use a ring buffer for call Tx
queue") this function is not used anymore.

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250312063450.183652-1-yuehaibing@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-03-18 13:04:12 +01:00
Ilpo Järvinen
023af5a72a gso: AccECN support
Handling the CWR flag differs between RFC 3168 ECN and AccECN.
With RFC 3168 ECN aware TSO (NETIF_F_TSO_ECN) CWR flag is cleared
starting from 2nd segment which is incompatible how AccECN handles
the CWR flag. Such super-segments are indicated by SKB_GSO_TCP_ECN.
With AccECN, CWR flag (or more accurately, the ACE field that also
includes ECE & AE flags) changes only when new packet(s) with CE
mark arrives so the flag should not be changed within a super-skb.
The new skb/feature flags are necessary to prevent such TSO engines
corrupting AccECN ACE counters by clearing the CWR flag (if the
CWR handling feature cannot be turned off).

If NIC is completely unaware of RFC3168 ECN (doesn't support
NETIF_F_TSO_ECN) or its TSO engine can be set to not touch CWR flag
despite supporting also NETIF_F_TSO_ECN, TSO could be safely used
with AccECN on such NIC. This should be evaluated per NIC basis
(not done in this patch series for any NICs).

For the cases, where TSO cannot keep its hands off the CWR flag,
a GSO fallback is provided by this patch.

Signed-off-by: Ilpo Järvinen <ij@kernel.org>
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2025-03-17 13:54:50 +00:00
Alexander Lobakin
859d6acd94 net: skbuff: introduce napi_skb_cache_get_bulk()
Add a function to get an array of skbs from the NAPI percpu cache.
It's supposed to be a drop-in replacement for
kmem_cache_alloc_bulk(skbuff_head_cache, GFP_ATOMIC) and
xdp_alloc_skb_bulk(GFP_ATOMIC). The difference (apart from the
requirement to call it only from the BH) is that it tries to use
as many NAPI cache entries for skbs as possible, and allocate new
ones only if needed.

The logic is as follows:

* there is enough skbs in the cache: decache them and return to the
  caller;
* not enough: try refilling the cache first. If there is now enough
  skbs, return;
* still not enough: try allocating skbs directly to the output array
  with %GFP_ZERO, maybe we'll be able to get some. If there's now
  enough, return;
* still not enough: return as many as we were able to obtain.

Most of times, if called from the NAPI polling loop, the first one will
be true, sometimes (rarely) the second one. The third and the fourth --
only under heavy memory pressure.
It can save significant amounts of CPU cycles if there are GRO cycles
and/or Tx completion cycles (anything that descends to
napi_skb_cache_put()) happening on this CPU.

Tested-by: Daniel Xu <dxu@dxuuu.xyz>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-02-27 14:03:14 +01:00
Willem de Bruijn
e6116fc605 net: skb: free up one bit in tx_flags
The linked series wants to add skb tx completion timestamps.
That needs a bit in skb_shared_info.tx_flags, but all are in use.

A per-skb bit is only needed for features that are configured on a
per packet basis. Per socket features can be read from sk->sk_tsflags.

Per packet tsflags can be set in sendmsg using cmsg, but only those in
SOF_TIMESTAMPING_TX_RECORD_MASK.

Per packet tsflags can also be set without cmsg by sandwiching a
send inbetween two setsockopts:

    val |= SOF_TIMESTAMPING_$FEATURE;
    setsockopt(fd, SOL_SOCKET, SO_TIMESTAMPING, &val, sizeof(val));
    write(fd, buf, sz);
    val &= ~SOF_TIMESTAMPING_$FEATURE;
    setsockopt(fd, SOL_SOCKET, SO_TIMESTAMPING, &val, sizeof(val));

Changing a datapath test from skb_shinfo(skb)->tx_flags to
skb->sk->sk_tsflags can change behavior in that case, as the tx_flags
is written before the second setsockopt updates sk_tsflags.

Therefore, only bits can be reclaimed that cannot be set by cmsg and
are also highly unlikely to be used to target individual packets
otherwise.

Free up the bit currently used for SKBTX_HW_TSTAMP_USE_CYCLES. This
selects between clock and free running counter source for HW TX
timestamps. It is probable that all packets of the same socket will
always use the same source.

Link: https://lore.kernel.org/netdev/cover.1739988644.git.pav@iki.fi/
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Reviewed-by: Gerhard Engleder <gerhard@engleder-embedded.com>
Link: https://patch.msgid.link/20250225023416.2088705-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-26 19:01:08 -08:00
Nicolas Dichtel
c52fd4f083 net: remove '__' from __skb_flow_get_ports()
Only one version of skb_flow_get_ports() exists after the previous commit,
so let's remove the useless '__'.

Suggested-by: Simon Horman <horms@kernel.org>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Link: https://patch.msgid.link/20250221110941.2041629-3-nicolas.dichtel@6wind.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-24 14:27:53 -08:00
Nicolas Dichtel
89ac4a59ca skbuff: kill skb_flow_get_ports()
Since commit a815bde56b ("net, bonding: Refactor bond_xmit_hash for use
with xdp_buff"), this function is not used anymore.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250221110941.2041629-2-nicolas.dichtel@6wind.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-24 14:27:53 -08:00
Jason Xing
2deaf7f42b bpf: Add BPF_SOCK_OPS_TSTAMP_SND_HW_CB callback
Support hw SCM_TSTAMP_SND case for bpf timestamping.

Add a new sock_ops callback, BPF_SOCK_OPS_TSTAMP_SND_HW_CB. This
callback will occur at the same timestamping point as the user
space's hardware SCM_TSTAMP_SND. The BPF program can use it to
get the same SCM_TSTAMP_SND timestamp without modifying the
user-space application.

To avoid increasing the code complexity, replace SKBTX_HW_TSTAMP
with SKBTX_HW_TSTAMP_NOBPF instead of changing numerous callers
from driver side using SKBTX_HW_TSTAMP. The new definition of
SKBTX_HW_TSTAMP means the combination tests of socket timestamping
and bpf timestamping. After this patch, drivers can work under the
bpf timestamping.

Considering some drivers don't assign the skb with hardware
timestamp, this patch does the assignment and then BPF program
can acquire the hwstamp from skb directly.

Signed-off-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250220072940.99994-9-kerneljasonxing@gmail.com
2025-02-20 14:29:36 -08:00
Jason Xing
ecebb17ad8 bpf: Add BPF_SOCK_OPS_TSTAMP_SND_SW_CB callback
Support sw SCM_TSTAMP_SND case for bpf timestamping.

Add a new sock_ops callback, BPF_SOCK_OPS_TSTAMP_SND_SW_CB. This
callback will occur at the same timestamping point as the user
space's software SCM_TSTAMP_SND. The BPF program can use it to
get the same SCM_TSTAMP_SND timestamp without modifying the
user-space application.

Based on this patch, BPF program will get the software
timestamp when the driver is ready to send the skb. In the
sebsequent patch, the hardware timestamp will be supported.

Signed-off-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250220072940.99994-8-kerneljasonxing@gmail.com
2025-02-20 14:29:30 -08:00
Jason Xing
6b98ec7e88 bpf: Add BPF_SOCK_OPS_TSTAMP_SCHED_CB callback
Support SCM_TSTAMP_SCHED case for bpf timestamping.

Add a new sock_ops callback, BPF_SOCK_OPS_TSTAMP_SCHED_CB. This
callback will occur at the same timestamping point as the user
space's SCM_TSTAMP_SCHED. The BPF program can use it to get the
same SCM_TSTAMP_SCHED timestamp without modifying the user-space
application.

A new SKBTX_BPF flag is added to mark skb_shinfo(skb)->tx_flags,
ensuring that the new BPF timestamping and the current user
space's SO_TIMESTAMPING do not interfere with each other.

Signed-off-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250220072940.99994-7-kerneljasonxing@gmail.com
2025-02-20 14:29:24 -08:00
Alexander Lobakin
68ddc8ae17 xdp: add generic xdp_buff_add_frag()
The code piece which would attach a frag to &xdp_buff is almost
identical across the drivers supporting XDP multi-buffer on Rx.
Make it a generic elegant "oneliner".
Also, I see lots of drivers calculating frags_truesize as
`xdp->frame_sz * nr_frags`. I can't say this is fully correct, since
frags might be backed by chunks of different sizes, especially with
stuff like the header split. Even page_pool_alloc() can give you two
different truesizes on two subsequent requests to allocate the same
buffer size. Add a field to &skb_shared_info (unionized as there's no
free slot currently on x86_64) to track the "true" truesize. It can
be used later when updating the skb.

Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://patch.msgid.link/20241218174435.1445282-3-aleksander.lobakin@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-19 19:51:13 -08:00
Alexander Lobakin
0dffdb3b33 skbuff: allow 2-4-argument skb_frag_dma_map()
skb_frag_dma_map(dev, frag, 0, skb_frag_size(frag), DMA_TO_DEVICE)
is repeated across dozens of drivers and really wants a shorthand.
Add a macro which will count args and handle all possible number
from 2 to 5. Semantics:

skb_frag_dma_map(dev, frag) ->
__skb_frag_dma_map(dev, frag, 0, skb_frag_size(frag), DMA_TO_DEVICE)

skb_frag_dma_map(dev, frag, offset) ->
__skb_frag_dma_map(dev, frag, offset, skb_frag_size(frag) - offset,
		   DMA_TO_DEVICE)

skb_frag_dma_map(dev, frag, offset, size) ->
__skb_frag_dma_map(dev, frag, offset, size, DMA_TO_DEVICE)

skb_frag_dma_map(dev, frag, offset, size, dir) ->
__skb_frag_dma_map(dev, frag, offset, size, dir)

No object code size changes for the existing callers. Users passing
less arguments also won't have bigger size comparing to the full
equivalent call.

Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://patch.msgid.link/20241211172649.761483-11-aleksander.lobakin@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-12 18:23:08 -08:00
Jakub Kicinski
3f330db306 net: reformat kdoc return statements
kernel-doc -Wall warns about missing Return: statement for non-void
functions. We have a number of kdocs in our headers which are missing
the colon, IOW they use
 * Return some value
or
 * Returns some value

Having the colon makes some sense, it should help kdoc parser avoid
false positives. So add them. This is mostly done with a sed script,
and removing the unnecessary cases (mostly the comments which aren't
kdoc).

Acked-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Acked-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Reviewed-by: Edward Cree <ecree.xilinx@gmail.com>
Acked-by: Alexandra Winter <wintera@linux.ibm.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Link: https://patch.msgid.link/20241205165914.1071102-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-09 14:44:59 -08:00
Alexander Lobakin
7cd1107f48 bpf, xdp: constify some bpf_prog * function arguments
In lots of places, bpf_prog pointer is used only for tracing or other
stuff that doesn't modify the structure itself. Same for net_device.
Address at least some of them and add `const` attributes there. The
object code didn't change, but that may prevent unwanted data
modifications and also allow more helpers to have const arguments.

Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-05 18:41:06 -08:00
Breno Leitao
12079a59ce net: Implement fault injection forcing skb reallocation
Introduce a fault injection mechanism to force skb reallocation. The
primary goal is to catch bugs related to pointer invalidation after
potential skb reallocation.

The fault injection mechanism aims to identify scenarios where callers
retain pointers to various headers in the skb but fail to reload these
pointers after calling a function that may reallocate the data. This
type of bug can lead to memory corruption or crashes if the old,
now-invalid pointers are used.

By forcing reallocation through fault injection, we can stress-test code
paths and ensure proper pointer management after potential skb
reallocations.

Add a hook for fault injection in the following functions:

 * pskb_trim_rcsum()
 * pskb_may_pull_reason()
 * pskb_trim()

As the other fault injection mechanism, protect it under a debug Kconfig
called CONFIG_FAIL_SKB_REALLOC.

This patch was *heavily* inspired by Jakub's proposal from:
https://lore.kernel.org/all/20240719174140.47a868e6@kernel.org/

CC: Akinobu Mita <akinobu.mita@gmail.com>
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Guillaume Nault <gnault@redhat.com>
Link: https://patch.msgid.link/20241107-fault_v6-v6-1-1b82cb6ecacd@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-11-12 12:05:33 +01:00
Yunsheng Lin
65941f10ca mm: move the page fragment allocator from page_alloc into its own file
Inspired by [1], move the page fragment allocator from page_alloc
into its own c file and header file, as we are about to make more
change for it to replace another page_frag implementation in
sock.c

As this patchset is going to replace 'struct page_frag' with
'struct page_frag_cache' in sched.h, including page_frag_cache.h
in sched.h has a compiler error caused by interdependence between
mm_types.h and mm.h for asm-offsets.c, see [2]. So avoid the compiler
error by moving 'struct page_frag_cache' to mm_types_task.h as
suggested by Alexander, see [3].

1. https://lore.kernel.org/all/20230411160902.4134381-3-dhowells@redhat.com/
2. https://lore.kernel.org/all/15623dac-9358-4597-b3ee-3694a5956920@gmail.com/
3. https://lore.kernel.org/all/CAKgT0UdH1yD=LSCXFJ=YM_aiA4OomD-2wXykO42bizaWMt_HOA@mail.gmail.com/
CC: David Howells <dhowells@redhat.com>
CC: Linux-MM <linux-mm@kvack.org>
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Link: https://patch.msgid.link/20241028115343.3405838-3-linyunsheng@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-11 10:56:26 -08:00
Eric Dumazet
3b6167e9bf net: add debug check in skb_reset_mac_header()
Make sure (skb->data - skb->head) can fit in skb->mac_header

This needs CONFIG_DEBUG_NET=y.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Link: https://patch.msgid.link/20241105174403.850330-8-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-06 17:29:15 -08:00
Eric Dumazet
305ae87daf net: add debug check in skb_reset_network_header()
Make sure (skb->data - skb->head) can fit in skb->network_header

This needs CONFIG_DEBUG_NET=y.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Link: https://patch.msgid.link/20241105174403.850330-7-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-06 17:29:15 -08:00
Eric Dumazet
ae50ea52bd net: add debug check in skb_reset_transport_header()
Make sure (skb->data - skb->head) can fit in skb->transport_header

This needs CONFIG_DEBUG_NET=y.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Link: https://patch.msgid.link/20241105174403.850330-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-06 17:29:14 -08:00
Eric Dumazet
78a0cb2f45 net: add debug check in skb_reset_inner_mac_header()
Make sure (skb->data - skb->head) can fit in skb->inner_mac_header

This needs CONFIG_DEBUG_NET=y.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Link: https://patch.msgid.link/20241105174403.850330-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-06 17:29:14 -08:00
Eric Dumazet
1732e4bedb net: add debug check in skb_reset_inner_network_header()
Make sure (skb->data - skb->head) can fit in skb->inner_network_header

This needs CONFIG_DEBUG_NET=y.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Link: https://patch.msgid.link/20241105174403.850330-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-06 17:29:14 -08:00
Eric Dumazet
cfe8394e06 net: add debug check in skb_reset_inner_transport_header()
Make sure (skb->data - skb->head) can fit in skb->inner_transport_header

This needs CONFIG_DEBUG_NET=y.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Link: https://patch.msgid.link/20241105174403.850330-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-06 17:29:14 -08:00
Eric Dumazet
1e4033b53d net: skb_reset_mac_len() must check if mac_header was set
Recent discussions show that skb_reset_mac_len() should be more careful.

We expect the MAC header being set.

If not, clear skb->mac_len and fire a warning for CONFIG_DEBUG_NET=y builds.

If after investigations we find that not having a MAC header was okay,
we can remove the warning.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/netdev/CANn89iJZGH+yEfJxfPWa3Hm7jxb-aeY2Up4HufmLMnVuQXt38A@mail.gmail.com/T/
Cc: En-Wei Wu <en-wei.wu@canonical.com>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Link: https://patch.msgid.link/20241105174403.850330-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-06 17:29:14 -08:00
Menglong Dong
454bbde8f0 net: skb: add pskb_network_may_pull_reason() helper
Introduce the function pskb_network_may_pull_reason() and make
pskb_network_may_pull() a simple inline call to it. The drop reasons of
it just come from pskb_may_pull_reason.

Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-10-13 11:33:08 +01:00
Mina Almasry
65249feb6b net: add support for skbs with unreadable frags
For device memory TCP, we expect the skb headers to be available in host
memory for access, and we expect the skb frags to be in device memory
and unaccessible to the host. We expect there to be no mixing and
matching of device memory frags (unaccessible) with host memory frags
(accessible) in the same skb.

Add a skb->devmem flag which indicates whether the frags in this skb
are device memory frags or not.

__skb_fill_netmem_desc() now checks frags added to skbs for net_iov,
and marks the skb as skb->devmem accordingly.

Add checks through the network stack to avoid accessing the frags of
devmem skbs and avoid coalescing devmem skbs with non devmem skbs.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Kaiyuan Zhang <kaiyuanz@google.com>
Signed-off-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://patch.msgid.link/20240910171458.219195-9-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-11 20:44:31 -07:00
Mina Almasry
9f6b619edf net: support non paged skb frags
Make skb_frag_page() fail in the case where the frag is not backed
by a page, and fix its relevant callers to handle this case.

Signed-off-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://patch.msgid.link/20240910171458.219195-8-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-11 20:44:31 -07:00
Jakub Kicinski
ea403549da ipsec-next-2024-09-10
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Merge tag 'ipsec-next-2024-09-10' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next

Steffen Klassert says:

====================
pull request (net-next): ipsec-next 2024-09-10

1) Remove an unneeded WARN_ON on packet offload.
   From Patrisious Haddad.

2) Add a copy from skb_seq_state to buffer function.
   This is needed for the upcomming IPTFS patchset.
   From Christian Hopps.

3) Spelling fix in xfrm.h.
   From Simon Horman.

4) Speed up xfrm policy insertions.
   From Florian Westphal.

5) Add and revert a patch to support xfrm interfaces
   for packet offload. This patch was just half cooked.

6) Extend usage of the new xfrm_policy_is_dead_or_sk helper.
   From Florian Westphal.

7) Update comments on sdb and xfrm_policy.
   From Florian Westphal.

8) Fix a null pointer dereference in the new policy insertion
   code From Florian Westphal.

9) Fix an uninitialized variable in the new policy insertion
   code. From Nathan Chancellor.

* tag 'ipsec-next-2024-09-10' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next:
  xfrm: policy: Restore dir assignments in xfrm_hash_rebuild()
  xfrm: policy: fix null dereference
  Revert "xfrm: add SA information to the offloaded packet"
  xfrm: minor update to sdb and xfrm_policy comments
  xfrm: policy: use recently added helper in more places
  xfrm: add SA information to the offloaded packet
  xfrm: policy: remove remaining use of inexact list
  xfrm: switch migrate to xfrm_policy_lookup_bytype
  xfrm: policy: don't iterate inexact policies twice at insert time
  selftests: add xfrm policy insertion speed test script
  xfrm: Correct spelling in xfrm.h
  net: add copy from skb_seq_state to buffer function
  xfrm: Remove documentation WARN_ON to limit return values for offloaded SA
====================

Link: https://patch.msgid.link/20240910065507.2436394-1-steffen.klassert@secunet.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-10 19:00:47 -07:00
Christian Hopps
6ad8bc92a4 net: add copy from skb_seq_state to buffer function
Add an skb helper function to copy a range of bytes from within
an existing skb_seq_state.

Signed-off-by: Christian Hopps <chopps@labn.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2024-08-20 08:11:48 +02:00
Breno Leitao
c9c0ee5f20 net: skbuff: Skip early return in skb_unref when debugging
This patch modifies the skb_unref function to skip the early return
optimization when CONFIG_DEBUG_NET is enabled. The change ensures that
the reference count decrement always occurs in debug builds, allowing
for more thorough checking of SKB reference counting.

Previously, when the SKB's reference count was 1 and CONFIG_DEBUG_NET
was not set, the function would return early after a memory barrier
(smp_rmb()) without decrementing the reference count. This optimization
assumes it's safe to proceed with freeing the SKB without the overhead
of an atomic decrement from 1 to 0.

With this change:
- In non-debug builds (CONFIG_DEBUG_NET not set), behavior remains
  unchanged, preserving the performance optimization.
- In debug builds (CONFIG_DEBUG_NET set), the reference count is always
  decremented, even when it's 1, allowing for consistent behavior and
  potentially catching subtle SKB management bugs.

This modification enhances debugging capabilities for networking code
without impacting performance in production kernels. It helps kernel
developers identify and diagnose issues related to SKB management and
reference counting in the network stack.

Cc: Chris Mason <clm@fb.com>
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20240729104741.370327-1-leitao@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-08-01 11:07:38 +02:00
Linus Torvalds
fbc90c042c - 875fa64577da ("mm/hugetlb_vmemmap: fix race with speculative PFN
walkers") is known to cause a performance regression
   (https://lore.kernel.org/all/3acefad9-96e5-4681-8014-827d6be71c7a@linux.ibm.com/T/#mfa809800a7862fb5bdf834c6f71a3a5113eb83ff).
   Yu has a fix which I'll send along later via the hotfixes branch.
 
 - In the series "mm: Avoid possible overflows in dirty throttling" Jan
   Kara addresses a couple of issues in the writeback throttling code.
   These fixes are also targetted at -stable kernels.
 
 - Ryusuke Konishi's series "nilfs2: fix potential issues related to
   reserved inodes" does that.  This should actually be in the
   mm-nonmm-stable tree, along with the many other nilfs2 patches.  My bad.
 
 - More folio conversions from Kefeng Wang in the series "mm: convert to
   folio_alloc_mpol()"
 
 - Kemeng Shi has sent some cleanups to the writeback code in the series
   "Add helper functions to remove repeated code and improve readability of
   cgroup writeback"
 
 - Kairui Song has made the swap code a little smaller and a little
   faster in the series "mm/swap: clean up and optimize swap cache index".
 
 - In the series "mm/memory: cleanly support zeropage in
   vm_insert_page*(), vm_map_pages*() and vmf_insert_mixed()" David
   Hildenbrand has reworked the rather sketchy handling of the use of the
   zeropage in MAP_SHARED mappings.  I don't see any runtime effects here -
   more a cleanup/understandability/maintainablity thing.
 
 - Dev Jain has improved selftests/mm/va_high_addr_switch.c's handling of
   higher addresses, for aarch64.  The (poorly named) series is
   "Restructure va_high_addr_switch".
 
 - The core TLB handling code gets some cleanups and possible slight
   optimizations in Bang Li's series "Add update_mmu_tlb_range() to
   simplify code".
 
 - Jane Chu has improved the handling of our
   fake-an-unrecoverable-memory-error testing feature MADV_HWPOISON in the
   series "Enhance soft hwpoison handling and injection".
 
 - Jeff Johnson has sent a billion patches everywhere to add
   MODULE_DESCRIPTION() to everything.  Some landed in this pull.
 
 - In the series "mm: cleanup MIGRATE_SYNC_NO_COPY mode", Kefeng Wang has
   simplified migration's use of hardware-offload memory copying.
 
 - Yosry Ahmed performs more folio API conversions in his series "mm:
   zswap: trivial folio conversions".
 
 - In the series "large folios swap-in: handle refault cases first",
   Chuanhua Han inches us forward in the handling of large pages in the
   swap code.  This is a cleanup and optimization, working toward the end
   objective of full support of large folio swapin/out.
 
 - In the series "mm,swap: cleanup VMA based swap readahead window
   calculation", Huang Ying has contributed some cleanups and a possible
   fixlet to his VMA based swap readahead code.
 
 - In the series "add mTHP support for anonymous shmem" Baolin Wang has
   taught anonymous shmem mappings to use multisize THP.  By default this
   is a no-op - users must opt in vis sysfs controls.  Dramatic
   improvements in pagefault latency are realized.
 
 - David Hildenbrand has some cleanups to our remaining use of
   page_mapcount() in the series "fs/proc: move page_mapcount() to
   fs/proc/internal.h".
 
 - David also has some highmem accounting cleanups in the series
   "mm/highmem: don't track highmem pages manually".
 
 - Build-time fixes and cleanups from John Hubbard in the series
   "cleanups, fixes, and progress towards avoiding "make headers"".
 
 - Cleanups and consolidation of the core pagemap handling from Barry
   Song in the series "mm: introduce pmd|pte_needs_soft_dirty_wp helpers
   and utilize them".
 
 - Lance Yang's series "Reclaim lazyfree THP without splitting" has
   reduced the latency of the reclaim of pmd-mapped THPs under fairly
   common circumstances.  A 10x speedup is seen in a microbenchmark.
 
   It does this by punting to aother CPU but I guess that's a win unless
   all CPUs are pegged.
 
 - hugetlb_cgroup cleanups from Xiu Jianfeng in the series
   "mm/hugetlb_cgroup: rework on cftypes".
 
 - Miaohe Lin's series "Some cleanups for memory-failure" does just that
   thing.
 
 - Is anyone reading this stuff?  If so, email me!
 
 - Someone other than SeongJae has developed a DAMON feature in Honggyu
   Kim's series "DAMON based tiered memory management for CXL memory".
   This adds DAMON features which may be used to help determine the
   efficiency of our placement of CXL/PCIe attached DRAM.
 
 - DAMON user API centralization and simplificatio work in SeongJae
   Park's series "mm/damon: introduce DAMON parameters online commit
   function".
 
 - In the series "mm: page_type, zsmalloc and page_mapcount_reset()"
   David Hildenbrand does some maintenance work on zsmalloc - partially
   modernizing its use of pageframe fields.
 
 - Kefeng Wang provides more folio conversions in the series "mm: remove
   page_maybe_dma_pinned() and page_mkclean()".
 
 - More cleanup from David Hildenbrand, this time in the series
   "mm/memory_hotplug: use PageOffline() instead of PageReserved() for
   !ZONE_DEVICE".  It "enlightens memory hotplug more about PageOffline()
   pages" and permits the removal of some virtio-mem hacks.
 
 - Barry Song's series "mm: clarify folio_add_new_anon_rmap() and
   __folio_add_anon_rmap()" is a cleanup to the anon folio handling in
   preparation for mTHP (multisize THP) swapin.
 
 - Kefeng Wang's series "mm: improve clear and copy user folio"
   implements more folio conversions, this time in the area of large folio
   userspace copying.
 
 - The series "Docs/mm/damon/maintaier-profile: document a mailing tool
   and community meetup series" tells people how to get better involved
   with other DAMON developers.  From SeongJae Park.
 
 - A large series ("kmsan: Enable on s390") from Ilya Leoshkevich does
   that.
 
 - David Hildenbrand sends along more cleanups, this time against the
   migration code.  The series is "mm/migrate: move NUMA hinting fault
   folio isolation + checks under PTL".
 
 - Jan Kara has found quite a lot of strangenesses and minor errors in
   the readahead code.  He addresses this in the series "mm: Fix various
   readahead quirks".
 
 - SeongJae Park's series "selftests/damon: test DAMOS tried regions and
   {min,max}_nr_regions" adds features and addresses errors in DAMON's self
   testing code.
 
 - Gavin Shan has found a userspace-triggerable WARN in the pagecache
   code.  The series "mm/filemap: Limit page cache size to that supported
   by xarray" addresses this.  The series is marked cc:stable.
 
 - Chengming Zhou's series "mm/ksm: cmp_and_merge_page() optimizations
   and cleanup" cleans up and slightly optimizes KSM.
 
 - Roman Gushchin has separated the memcg-v1 and memcg-v2 code - lots of
   code motion.  The series (which also makes the memcg-v1 code
   Kconfigurable) are
 
   "mm: memcg: separate legacy cgroup v1 code and put under config
   option" and
   "mm: memcg: put cgroup v1-specific memcg data under CONFIG_MEMCG_V1"
 
 - Dan Schatzberg's series "Add swappiness argument to memory.reclaim"
   adds an additional feature to this cgroup-v2 control file.
 
 - The series "Userspace controls soft-offline pages" from Jiaqi Yan
   permits userspace to stop the kernel's automatic treatment of excessive
   correctable memory errors.  In order to permit userspace to monitor and
   handle this situation.
 
 - Kefeng Wang's series "mm: migrate: support poison recover from migrate
   folio" teaches the kernel to appropriately handle migration from
   poisoned source folios rather than simply panicing.
 
 - SeongJae Park's series "Docs/damon: minor fixups and improvements"
   does those things.
 
 - In the series "mm/zsmalloc: change back to per-size_class lock"
   Chengming Zhou improves zsmalloc's scalability and memory utilization.
 
 - Vivek Kasireddy's series "mm/gup: Introduce memfd_pin_folios() for
   pinning memfd folios" makes the GUP code use FOLL_PIN rather than bare
   refcount increments.  So these paes can first be moved aside if they
   reside in the movable zone or a CMA block.
 
 - Andrii Nakryiko has added a binary ioctl()-based API to /proc/pid/maps
   for much faster reading of vma information.  The series is "query VMAs
   from /proc/<pid>/maps".
 
 - In the series "mm: introduce per-order mTHP split counters" Lance Yang
   improves the kernel's presentation of developer information related to
   multisize THP splitting.
 
 - Michael Ellerman has developed the series "Reimplement huge pages
   without hugepd on powerpc (8xx, e500, book3s/64)".  This permits
   userspace to use all available huge page sizes.
 
 - In the series "revert unconditional slab and page allocator fault
   injection calls" Vlastimil Babka removes a performance-affecting and not
   very useful feature from slab fault injection.
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Merge tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - In the series "mm: Avoid possible overflows in dirty throttling" Jan
   Kara addresses a couple of issues in the writeback throttling code.
   These fixes are also targetted at -stable kernels.

 - Ryusuke Konishi's series "nilfs2: fix potential issues related to
   reserved inodes" does that. This should actually be in the
   mm-nonmm-stable tree, along with the many other nilfs2 patches. My
   bad.

 - More folio conversions from Kefeng Wang in the series "mm: convert to
   folio_alloc_mpol()"

 - Kemeng Shi has sent some cleanups to the writeback code in the series
   "Add helper functions to remove repeated code and improve readability
   of cgroup writeback"

 - Kairui Song has made the swap code a little smaller and a little
   faster in the series "mm/swap: clean up and optimize swap cache
   index".

 - In the series "mm/memory: cleanly support zeropage in
   vm_insert_page*(), vm_map_pages*() and vmf_insert_mixed()" David
   Hildenbrand has reworked the rather sketchy handling of the use of
   the zeropage in MAP_SHARED mappings. I don't see any runtime effects
   here - more a cleanup/understandability/maintainablity thing.

 - Dev Jain has improved selftests/mm/va_high_addr_switch.c's handling
   of higher addresses, for aarch64. The (poorly named) series is
   "Restructure va_high_addr_switch".

 - The core TLB handling code gets some cleanups and possible slight
   optimizations in Bang Li's series "Add update_mmu_tlb_range() to
   simplify code".

 - Jane Chu has improved the handling of our
   fake-an-unrecoverable-memory-error testing feature MADV_HWPOISON in
   the series "Enhance soft hwpoison handling and injection".

 - Jeff Johnson has sent a billion patches everywhere to add
   MODULE_DESCRIPTION() to everything. Some landed in this pull.

 - In the series "mm: cleanup MIGRATE_SYNC_NO_COPY mode", Kefeng Wang
   has simplified migration's use of hardware-offload memory copying.

 - Yosry Ahmed performs more folio API conversions in his series "mm:
   zswap: trivial folio conversions".

 - In the series "large folios swap-in: handle refault cases first",
   Chuanhua Han inches us forward in the handling of large pages in the
   swap code. This is a cleanup and optimization, working toward the end
   objective of full support of large folio swapin/out.

 - In the series "mm,swap: cleanup VMA based swap readahead window
   calculation", Huang Ying has contributed some cleanups and a possible
   fixlet to his VMA based swap readahead code.

 - In the series "add mTHP support for anonymous shmem" Baolin Wang has
   taught anonymous shmem mappings to use multisize THP. By default this
   is a no-op - users must opt in vis sysfs controls. Dramatic
   improvements in pagefault latency are realized.

 - David Hildenbrand has some cleanups to our remaining use of
   page_mapcount() in the series "fs/proc: move page_mapcount() to
   fs/proc/internal.h".

 - David also has some highmem accounting cleanups in the series
   "mm/highmem: don't track highmem pages manually".

 - Build-time fixes and cleanups from John Hubbard in the series
   "cleanups, fixes, and progress towards avoiding "make headers"".

 - Cleanups and consolidation of the core pagemap handling from Barry
   Song in the series "mm: introduce pmd|pte_needs_soft_dirty_wp helpers
   and utilize them".

 - Lance Yang's series "Reclaim lazyfree THP without splitting" has
   reduced the latency of the reclaim of pmd-mapped THPs under fairly
   common circumstances. A 10x speedup is seen in a microbenchmark.

   It does this by punting to aother CPU but I guess that's a win unless
   all CPUs are pegged.

 - hugetlb_cgroup cleanups from Xiu Jianfeng in the series
   "mm/hugetlb_cgroup: rework on cftypes".

 - Miaohe Lin's series "Some cleanups for memory-failure" does just that
   thing.

 - Someone other than SeongJae has developed a DAMON feature in Honggyu
   Kim's series "DAMON based tiered memory management for CXL memory".
   This adds DAMON features which may be used to help determine the
   efficiency of our placement of CXL/PCIe attached DRAM.

 - DAMON user API centralization and simplificatio work in SeongJae
   Park's series "mm/damon: introduce DAMON parameters online commit
   function".

 - In the series "mm: page_type, zsmalloc and page_mapcount_reset()"
   David Hildenbrand does some maintenance work on zsmalloc - partially
   modernizing its use of pageframe fields.

 - Kefeng Wang provides more folio conversions in the series "mm: remove
   page_maybe_dma_pinned() and page_mkclean()".

 - More cleanup from David Hildenbrand, this time in the series
   "mm/memory_hotplug: use PageOffline() instead of PageReserved() for
   !ZONE_DEVICE". It "enlightens memory hotplug more about PageOffline()
   pages" and permits the removal of some virtio-mem hacks.

 - Barry Song's series "mm: clarify folio_add_new_anon_rmap() and
   __folio_add_anon_rmap()" is a cleanup to the anon folio handling in
   preparation for mTHP (multisize THP) swapin.

 - Kefeng Wang's series "mm: improve clear and copy user folio"
   implements more folio conversions, this time in the area of large
   folio userspace copying.

 - The series "Docs/mm/damon/maintaier-profile: document a mailing tool
   and community meetup series" tells people how to get better involved
   with other DAMON developers. From SeongJae Park.

 - A large series ("kmsan: Enable on s390") from Ilya Leoshkevich does
   that.

 - David Hildenbrand sends along more cleanups, this time against the
   migration code. The series is "mm/migrate: move NUMA hinting fault
   folio isolation + checks under PTL".

 - Jan Kara has found quite a lot of strangenesses and minor errors in
   the readahead code. He addresses this in the series "mm: Fix various
   readahead quirks".

 - SeongJae Park's series "selftests/damon: test DAMOS tried regions and
   {min,max}_nr_regions" adds features and addresses errors in DAMON's
   self testing code.

 - Gavin Shan has found a userspace-triggerable WARN in the pagecache
   code. The series "mm/filemap: Limit page cache size to that supported
   by xarray" addresses this. The series is marked cc:stable.

 - Chengming Zhou's series "mm/ksm: cmp_and_merge_page() optimizations
   and cleanup" cleans up and slightly optimizes KSM.

 - Roman Gushchin has separated the memcg-v1 and memcg-v2 code - lots of
   code motion. The series (which also makes the memcg-v1 code
   Kconfigurable) are "mm: memcg: separate legacy cgroup v1 code and put
   under config option" and "mm: memcg: put cgroup v1-specific memcg
   data under CONFIG_MEMCG_V1"

 - Dan Schatzberg's series "Add swappiness argument to memory.reclaim"
   adds an additional feature to this cgroup-v2 control file.

 - The series "Userspace controls soft-offline pages" from Jiaqi Yan
   permits userspace to stop the kernel's automatic treatment of
   excessive correctable memory errors. In order to permit userspace to
   monitor and handle this situation.

 - Kefeng Wang's series "mm: migrate: support poison recover from
   migrate folio" teaches the kernel to appropriately handle migration
   from poisoned source folios rather than simply panicing.

 - SeongJae Park's series "Docs/damon: minor fixups and improvements"
   does those things.

 - In the series "mm/zsmalloc: change back to per-size_class lock"
   Chengming Zhou improves zsmalloc's scalability and memory
   utilization.

 - Vivek Kasireddy's series "mm/gup: Introduce memfd_pin_folios() for
   pinning memfd folios" makes the GUP code use FOLL_PIN rather than
   bare refcount increments. So these paes can first be moved aside if
   they reside in the movable zone or a CMA block.

 - Andrii Nakryiko has added a binary ioctl()-based API to
   /proc/pid/maps for much faster reading of vma information. The series
   is "query VMAs from /proc/<pid>/maps".

 - In the series "mm: introduce per-order mTHP split counters" Lance
   Yang improves the kernel's presentation of developer information
   related to multisize THP splitting.

 - Michael Ellerman has developed the series "Reimplement huge pages
   without hugepd on powerpc (8xx, e500, book3s/64)". This permits
   userspace to use all available huge page sizes.

 - In the series "revert unconditional slab and page allocator fault
   injection calls" Vlastimil Babka removes a performance-affecting and
   not very useful feature from slab fault injection.

* tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (411 commits)
  mm/mglru: fix ineffective protection calculation
  mm/zswap: fix a white space issue
  mm/hugetlb: fix kernel NULL pointer dereference when migrating hugetlb folio
  mm/hugetlb: fix possible recursive locking detected warning
  mm/gup: clear the LRU flag of a page before adding to LRU batch
  mm/numa_balancing: teach mpol_to_str about the balancing mode
  mm: memcg1: convert charge move flags to unsigned long long
  alloc_tag: fix page_ext_get/page_ext_put sequence during page splitting
  lib: reuse page_ext_data() to obtain codetag_ref
  lib: add missing newline character in the warning message
  mm/mglru: fix overshooting shrinker memory
  mm/mglru: fix div-by-zero in vmpressure_calc_level()
  mm/kmemleak: replace strncpy() with strscpy()
  mm, page_alloc: put should_fail_alloc_page() back behing CONFIG_FAIL_PAGE_ALLOC
  mm, slab: put should_failslab() back behind CONFIG_SHOULD_FAILSLAB
  mm: ignore data-race in __swap_writepage
  hugetlbfs: ensure generic_hugetlb_get_unmapped_area() returns higher address than mmap_min_addr
  mm: shmem: rename mTHP shmem counters
  mm: swap_state: use folio_alloc_mpol() in __read_swap_cache_async()
  mm/migrate: putback split folios when numa hint migration fails
  ...
2024-07-21 17:15:46 -07:00
Suren Baghdasaryan
3b0ba54d5f mm: add comments for allocation helpers explaining why they are macros
A number of allocation helper functions were converted into macros to
account them at the call sites.  Add a comment for each converted
allocation helper explaining why it has to be a macro and why we typecast
the return value wherever required.  The patch also moves
acpi_os_acquire_object() closer to other allocation helpers to group them
together under the same comment.  The patch has no functional changes.

Link: https://lkml.kernel.org/r/20240703174225.3891393-1-surenb@google.com
Fixes: 2c321f3f70 ("mm: change inlined allocation helpers to account at the call site")
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christian König <christian.koenig@amd.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.cz>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Thorsten Blum <thorsten.blum@toblux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-12 15:52:20 -07:00
Pavel Begunkov
060f4ba6e4 io_uring/net: move charging socket out of zc io_uring
Currently, io_uring's io_sg_from_iter() duplicates the part of
__zerocopy_sg_from_iter() charging pages to the socket. It'd be too easy
to miss while changing it in net/, the chunk is not the most
straightforward for outside users and full of internal implementation
details. io_uring is not a good place to keep it, deduplicate it by
moving out of the callback into __zerocopy_sg_from_iter().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-07-02 12:06:50 +02:00
Yan Zhai
ba8de796ba net: introduce sk_skb_reason_drop function
Long used destructors kfree_skb and kfree_skb_reason do not pass
receiving socket to packet drop tracepoints trace_kfree_skb.
This makes it hard to track packet drops of a certain netns (container)
or a socket (user application).

The naming of these destructors are also not consistent with most sk/skb
operating functions, i.e. functions named "sk_xxx" or "skb_xxx".
Introduce a new functions sk_skb_reason_drop as drop-in replacement for
kfree_skb_reason on local receiving path. Callers can now pass receiving
sockets to the tracepoints.

kfree_skb and kfree_skb_reason are still usable but they are now just
inline helpers that call sk_skb_reason_drop.

Note it is not feasible to do the same to consume_skb. Packets not
dropped can flow through multiple receive handlers, and have multiple
receiving sockets. Leave it untouched for now.

Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yan Zhai <yan@cloudflare.com>
Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-19 12:44:22 +01:00
Florian Westphal
d1dab4f71d net: add and use __skb_get_hash_symmetric_net
Similar to previous patch: apply same logic for
__skb_get_hash_symmetric and let callers pass the netns to the dissector
core.

Existing function is turned into a wrapper to avoid adjusting all
callers, nft_hash.c uses new function.

Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240608221057.16070-3-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-12 14:33:38 -07:00
Florian Westphal
b975d3ee59 net: add and use skb_get_hash_net
Years ago flow dissector gained ability to delegate flow dissection
to a bpf program, scoped per netns.

Unfortunately, skb_get_hash() only gets an sk_buff argument instead
of both net+skb.  This means the flow dissector needs to obtain the
netns pointer from somewhere else.

The netns is derived from skb->dev, and if that is not available, from
skb->sk.  If neither is set, we hit a (benign) WARN_ON_ONCE().

Trying both dev and sk covers most cases, but not all, as recently
reported by Christoph Paasch.

In case of nf-generated tcp reset, both sk and dev are NULL:

WARNING: .. net/core/flow_dissector.c:1104
 skb_flow_dissect_flow_keys include/linux/skbuff.h:1536 [inline]
 skb_get_hash include/linux/skbuff.h:1578 [inline]
 nft_trace_init+0x7d/0x120 net/netfilter/nf_tables_trace.c:320
 nft_do_chain+0xb26/0xb90 net/netfilter/nf_tables_core.c:268
 nft_do_chain_ipv4+0x7a/0xa0 net/netfilter/nft_chain_filter.c:23
 nf_hook_slow+0x57/0x160 net/netfilter/core.c:626
 __ip_local_out+0x21d/0x260 net/ipv4/ip_output.c:118
 ip_local_out+0x26/0x1e0 net/ipv4/ip_output.c:127
 nf_send_reset+0x58c/0x700 net/ipv4/netfilter/nf_reject_ipv4.c:308
 nft_reject_ipv4_eval+0x53/0x90 net/ipv4/netfilter/nft_reject_ipv4.c:30
 [..]

syzkaller did something like this:
table inet filter {
  chain input {
    type filter hook input priority filter; policy accept;
    meta nftrace set 1
    tcp dport 42 reject with tcp reset
   }
   chain output {
    type filter hook output priority filter; policy accept;
    # empty chain is enough
   }
}

... then sends a tcp packet to port 42.

Initial attempt to simply set skb->dev from nf_reject_ipv4 doesn't cover
all cases: skbs generated via ipv4 igmp_send_report trigger similar splat.

Moreover, Pablo Neira found that nft_hash.c uses __skb_get_hash_symmetric()
which would trigger same warn splat for such skbs.

Lets allow callers to pass the current netns explicitly.
The nf_trace infrastructure is adjusted to use the new helper.

__skb_get_hash_symmetric is handled in the next patch.

Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/494
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240608221057.16070-2-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-12 14:33:38 -07:00
Jakub Kicinski
4b3529edbb bpf-next-for-netdev
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2024-05-28

We've added 23 non-merge commits during the last 11 day(s) which contain
a total of 45 files changed, 696 insertions(+), 277 deletions(-).

The main changes are:

1) Rename skb's mono_delivery_time to tstamp_type for extensibility
   and add SKB_CLOCK_TAI type support to bpf_skb_set_tstamp(),
   from Abhishek Chauhan.

2) Add netfilter CT zone ID and direction to bpf_ct_opts so that arbitrary
   CT zones can be used from XDP/tc BPF netfilter CT helper functions,
   from Brad Cowie.

3) Several tweaks to the instruction-set.rst IETF doc to address
   the Last Call review comments, from Dave Thaler.

4) Small batch of riscv64 BPF JIT optimizations in order to emit more
   compressed instructions to the JITed image for better icache efficiency,
   from Xiao Wang.

5) Sort bpftool C dump output from BTF, aiming to simplify vmlinux.h
   diffing and forcing more natural type definitions ordering,
   from Mykyta Yatsenko.

6) Use DEV_STATS_INC() macro in BPF redirect helpers to silence
   a syzbot/KCSAN race report for the tx_errors counter,
   from Jiang Yunshui.

7) Un-constify bpf_func_info in bpftool to fix compilation with LLVM 17+
   which started treating const structs as constants and thus breaking
   full BTF program name resolution, from Ivan Babrou.

8) Fix up BPF program numbers in test_sockmap selftest in order to reduce
   some of the test-internal array sizes, from Geliang Tang.

9) Small cleanup in Makefile.btf script to use test-ge check for v1.25-only
   pahole, from Alan Maguire.

10) Fix bpftool's make dependencies for vmlinux.h in order to avoid needless
    rebuilds in some corner cases, from Artem Savkov.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (23 commits)
  bpf, net: Use DEV_STAT_INC()
  bpf, docs: Fix instruction.rst indentation
  bpf, docs: Clarify call local offset
  bpf, docs: Add table captions
  bpf, docs: clarify sign extension of 64-bit use of 32-bit imm
  bpf, docs: Use RFC 2119 language for ISA requirements
  bpf, docs: Move sentence about returning R0 to abi.rst
  bpf: constify member bpf_sysctl_kern:: Table
  riscv, bpf: Try RVC for reg move within BPF_CMPXCHG JIT
  riscv, bpf: Use STACK_ALIGN macro for size rounding up
  riscv, bpf: Optimize zextw insn with Zba extension
  selftests/bpf: Handle forwarding of UDP CLOCK_TAI packets
  net: Add additional bit to support clockid_t timestamp type
  net: Rename mono_delivery_time to tstamp_type for scalabilty
  selftests/bpf: Update tests for new ct zone opts for nf_conntrack kfuncs
  net: netfilter: Make ct zone opts configurable for bpf ct helpers
  selftests/bpf: Fix prog numbers in test_sockmap
  bpf: Remove unused variable "prev_state"
  bpftool: Un-const bpf_func_info to fix it for llvm 17 and newer
  bpf: Fix order of args in call to bpf_map_kvcalloc
  ...
====================

Link: https://lore.kernel.org/r/20240528105924.30905-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-28 07:27:29 -07:00
Abhishek Chauhan
1693c5db6a net: Add additional bit to support clockid_t timestamp type
tstamp_type is now set based on actual clockid_t compressed
into 2 bits.

To make the design scalable for future needs this commit bring in
the change to extend the tstamp_type:1 to tstamp_type:2 to support
other clockid_t timestamp.

We now support CLOCK_TAI as part of tstamp_type as part of this
commit with existing support CLOCK_MONOTONIC and CLOCK_REALTIME.

Signed-off-by: Abhishek Chauhan <quic_abchauha@quicinc.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240509211834.3235191-3-quic_abchauha@quicinc.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-05-23 14:14:36 -07:00