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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
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+============
+LITMUS TESTS
+============
+
+CoRR+poonceonce+Once.litmus
+ Test of read-read coherence, that is, whether or not two
+ successive reads from the same variable are ordered.
+
+CoRW+poonceonce+Once.litmus
+ Test of read-write coherence, that is, whether or not a read
+ from a given variable followed by a write to that same variable
+ are ordered.
+
+CoWR+poonceonce+Once.litmus
+ Test of write-read coherence, that is, whether or not a write
+ to a given variable followed by a read from that same variable
+ are ordered.
+
+CoWW+poonceonce.litmus
+ Test of write-write coherence, that is, whether or not two
+ successive writes to the same variable are ordered.
+
+IRIW+fencembonceonces+OnceOnce.litmus
+ Test of independent reads from independent writes with smp_mb()
+ between each pairs of reads. In other words, is smp_mb()
+ sufficient to cause two different reading processes to agree on
+ the order of a pair of writes, where each write is to a different
+ variable by a different process? This litmus test is forbidden
+ by LKMM's propagation rule.
+
+IRIW+poonceonces+OnceOnce.litmus
+ Test of independent reads from independent writes with nothing
+ between each pairs of reads. In other words, is anything at all
+ needed to cause two different reading processes to agree on the
+ order of a pair of writes, where each write is to a different
+ variable by a different process?
+
+ISA2+pooncelock+pooncelock+pombonce.litmus
+ Tests whether the ordering provided by a lock-protected S
+ litmus test is visible to an external process whose accesses are
+ separated by smp_mb(). This addition of an external process to
+ S is otherwise known as ISA2.
+
+ISA2+poonceonces.litmus
+ As below, but with store-release replaced with WRITE_ONCE()
+ and load-acquire replaced with READ_ONCE().
+
+ISA2+pooncerelease+poacquirerelease+poacquireonce.litmus
+ Can a release-acquire chain order a prior store against
+ a later load?
+
+LB+fencembonceonce+ctrlonceonce.litmus
+ Does a control dependency and an smp_mb() suffice for the
+ load-buffering litmus test, where each process reads from one
+ of two variables then writes to the other?
+
+LB+poacquireonce+pooncerelease.litmus
+ Does a release-acquire pair suffice for the load-buffering
+ litmus test, where each process reads from one of two variables then
+ writes to the other?
+
+LB+poonceonces.litmus
+ As above, but with store-release replaced with WRITE_ONCE()
+ and load-acquire replaced with READ_ONCE().
+
+LB+unlocklockonceonce+poacquireonce.litmus
+ Does a unlock+lock pair provides ordering guarantee between a
+ load and a store?
+
+MP+onceassign+derefonce.litmus
+ As below, but with rcu_assign_pointer() and an rcu_dereference().
+
+MP+polockmbonce+poacquiresilsil.litmus
+ Protect the access with a lock and an smp_mb__after_spinlock()
+ in one process, and use an acquire load followed by a pair of
+ spin_is_locked() calls in the other process.
+
+MP+polockonce+poacquiresilsil.litmus
+ Protect the access with a lock in one process, and use an
+ acquire load followed by a pair of spin_is_locked() calls
+ in the other process.
+
+MP+polocks.litmus
+ As below, but with the second access of the writer process
+ and the first access of reader process protected by a lock.
+
+MP+poonceonces.litmus
+ As below, but without the smp_rmb() and smp_wmb().
+
+MP+pooncerelease+poacquireonce.litmus
+ As below, but with a release-acquire chain.
+
+MP+porevlocks.litmus
+ As below, but with the first access of the writer process
+ and the second access of reader process protected by a lock.
+
+MP+unlocklockonceonce+fencermbonceonce.litmus
+ Does a unlock+lock pair provides ordering guarantee between a
+ store and another store?
+
+MP+fencewmbonceonce+fencermbonceonce.litmus
+ Does a smp_wmb() (between the stores) and an smp_rmb() (between
+ the loads) suffice for the message-passing litmus test, where one
+ process writes data and then a flag, and the other process reads
+ the flag and then the data. (This is similar to the ISA2 tests,
+ but with two processes instead of three.)
+
+R+fencembonceonces.litmus
+ This is the fully ordered (via smp_mb()) version of one of
+ the classic counterintuitive litmus tests that illustrates the
+ effects of store propagation delays.
+
+R+poonceonces.litmus
+ As above, but without the smp_mb() invocations.
+
+SB+fencembonceonces.litmus
+ This is the fully ordered (again, via smp_mb() version of store
+ buffering, which forms the core of Dekker's mutual-exclusion
+ algorithm.
+
+SB+poonceonces.litmus
+ As above, but without the smp_mb() invocations.
+
+SB+rfionceonce-poonceonces.litmus
+ This litmus test demonstrates that LKMM is not fully multicopy
+ atomic. (Neither is it other multicopy atomic.) This litmus test
+ also demonstrates the "locations" debugging aid, which designates
+ additional registers and locations to be printed out in the dump
+ of final states in the herd7 output. Without the "locations"
+ statement, only those registers and locations mentioned in the
+ "exists" clause will be printed.
+
+S+poonceonces.litmus
+ As below, but without the smp_wmb() and acquire load.
+
+S+fencewmbonceonce+poacquireonce.litmus
+ Can a smp_wmb(), instead of a release, and an acquire order
+ a prior store against a subsequent store?
+
+WRC+poonceonces+Once.litmus
+WRC+pooncerelease+fencermbonceonce+Once.litmus
+ These two are members of an extension of the MP litmus-test
+ class in which the first write is moved to a separate process.
+ The second is forbidden because smp_store_release() is
+ A-cumulative in LKMM.
+
+Z6.0+pooncelock+pooncelock+pombonce.litmus
+ Is the ordering provided by a spin_unlock() and a subsequent
+ spin_lock() sufficient to make ordering apparent to accesses
+ by a process not holding the lock?
+
+Z6.0+pooncelock+poonceLock+pombonce.litmus
+ As above, but with smp_mb__after_spinlock() immediately
+ following the spin_lock().
+
+Z6.0+pooncerelease+poacquirerelease+fencembonceonce.litmus
+ Is the ordering provided by a release-acquire chain sufficient
+ to make ordering apparent to accesses by a process that does
+ not participate in that release-acquire chain?
+
+A great many more litmus tests are available here:
+
+ https://github.com/paulmckrcu/litmus
+
+==================
+LITMUS TEST NAMING
+==================
+
+Litmus tests are usually named based on their contents, which means that
+looking at the name tells you what the litmus test does. The naming
+scheme covers litmus tests having a single cycle that passes through
+each process exactly once, so litmus tests not fitting this description
+are named on an ad-hoc basis.
+
+The structure of a litmus-test name is the litmus-test class, a plus
+sign ("+"), and one string for each process, separated by plus signs.
+The end of the name is ".litmus".
+
+The litmus-test classes may be found in the infamous test6.pdf:
+https://www.cl.cam.ac.uk/~pes20/ppc-supplemental/test6.pdf
+Each class defines the pattern of accesses and of the variables accessed.
+For example, if the one process writes to a pair of variables, and
+the other process reads from these same variables, the corresponding
+litmus-test class is "MP" (message passing), which may be found on the
+left-hand end of the second row of tests on page one of test6.pdf.
+
+The strings used to identify the actions carried out by each process are
+complex due to a desire to have short(er) names. Thus, there is a tool to
+generate these strings from a given litmus test's actions. For example,
+consider the processes from SB+rfionceonce-poonceonces.litmus:
+
+ P0(int *x, int *y)
+ {
+ int r1;
+ int r2;
+
+ WRITE_ONCE(*x, 1);
+ r1 = READ_ONCE(*x);
+ r2 = READ_ONCE(*y);
+ }
+
+ P1(int *x, int *y)
+ {
+ int r3;
+ int r4;
+
+ WRITE_ONCE(*y, 1);
+ r3 = READ_ONCE(*y);
+ r4 = READ_ONCE(*x);
+ }
+
+The next step is to construct a space-separated list of descriptors,
+interleaving descriptions of the relation between a pair of consecutive
+accesses with descriptions of the second access in the pair.
+
+P0()'s WRITE_ONCE() is read by its first READ_ONCE(), which is a
+reads-from link (rf) and internal to the P0() process. This is
+"rfi", which is an abbreviation for "reads-from internal". Because
+some of the tools string these abbreviations together with space
+characters separating processes, the first character is capitalized,
+resulting in "Rfi".
+
+P0()'s second access is a READ_ONCE(), as opposed to (for example)
+smp_load_acquire(), so next is "Once". Thus far, we have "Rfi Once".
+
+P0()'s third access is also a READ_ONCE(), but to y rather than x.
+This is related to P0()'s second access by program order ("po"),
+to a different variable ("d"), and both accesses are reads ("RR").
+The resulting descriptor is "PodRR". Because P0()'s third access is
+READ_ONCE(), we add another "Once" descriptor.
+
+A from-read ("fre") relation links P0()'s third to P1()'s first
+access, and the resulting descriptor is "Fre". P1()'s first access is
+WRITE_ONCE(), which as before gives the descriptor "Once". The string
+thus far is thus "Rfi Once PodRR Once Fre Once".
+
+The remainder of P1() is similar to P0(), which means we add
+"Rfi Once PodRR Once". Another fre links P1()'s last access to
+P0()'s first access, which is WRITE_ONCE(), so we add "Fre Once".
+The full string is thus:
+
+ Rfi Once PodRR Once Fre Once Rfi Once PodRR Once Fre Once
+
+This string can be given to the "norm7" and "classify7" tools to
+produce the name:
+
+ $ norm7 -bell linux-kernel.bell \
+ Rfi Once PodRR Once Fre Once Rfi Once PodRR Once Fre Once | \
+ sed -e 's/:.*//g'
+ SB+rfionceonce-poonceonces
+
+Adding the ".litmus" suffix: SB+rfionceonce-poonceonces.litmus
+
+The descriptors that describe connections between consecutive accesses
+within the cycle through a given litmus test can be provided by the herd7
+tool (Rfi, Po, Fre, and so on) or by the linux-kernel.bell file (Once,
+Release, Acquire, and so on).
+
+To see the full list of descriptors, execute the following command:
+
+ $ diyone7 -bell linux-kernel.bell -show edges