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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
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
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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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+.. SPDX-License-Identifier: GPL-2.0
+
+=========================================
+s390 (IBM Z) Ultravisor and Protected VMs
+=========================================
+
+Summary
+-------
+Protected virtual machines (PVM) are KVM VMs that do not allow KVM to
+access VM state like guest memory or guest registers. Instead, the
+PVMs are mostly managed by a new entity called Ultravisor (UV). The UV
+provides an API that can be used by PVMs and KVM to request management
+actions.
+
+Each guest starts in non-protected mode and then may make a request to
+transition into protected mode. On transition, KVM registers the guest
+and its VCPUs with the Ultravisor and prepares everything for running
+it.
+
+The Ultravisor will secure and decrypt the guest's boot memory
+(i.e. kernel/initrd). It will safeguard state changes like VCPU
+starts/stops and injected interrupts while the guest is running.
+
+As access to the guest's state, such as the SIE state description, is
+normally needed to be able to run a VM, some changes have been made in
+the behavior of the SIE instruction. A new format 4 state description
+has been introduced, where some fields have different meanings for a
+PVM. SIE exits are minimized as much as possible to improve speed and
+reduce exposed guest state.
+
+
+Interrupt injection
+-------------------
+Interrupt injection is safeguarded by the Ultravisor. As KVM doesn't
+have access to the VCPUs' lowcores, injection is handled via the
+format 4 state description.
+
+Machine check, external, IO and restart interruptions each can be
+injected on SIE entry via a bit in the interrupt injection control
+field (offset 0x54). If the guest cpu is not enabled for the interrupt
+at the time of injection, a validity interception is recognized. The
+format 4 state description contains fields in the interception data
+block where data associated with the interrupt can be transported.
+
+Program and Service Call exceptions have another layer of
+safeguarding; they can only be injected for instructions that have
+been intercepted into KVM. The exceptions need to be a valid outcome
+of an instruction emulation by KVM, e.g. we can never inject a
+addressing exception as they are reported by SIE since KVM has no
+access to the guest memory.
+
+
+Mask notification interceptions
+-------------------------------
+KVM cannot intercept lctl(g) and lpsw(e) anymore in order to be
+notified when a PVM enables a certain class of interrupt. As a
+replacement, two new interception codes have been introduced: One
+indicating that the contents of CRs 0, 6, or 14 have been changed,
+indicating different interruption subclasses; and one indicating that
+PSW bit 13 has been changed, indicating that a machine check
+intervention was requested and those are now enabled.
+
+Instruction emulation
+---------------------
+With the format 4 state description for PVMs, the SIE instruction already
+interprets more instructions than it does with format 2. It is not able
+to interpret every instruction, but needs to hand some tasks to KVM;
+therefore, the SIE and the ultravisor safeguard emulation inputs and outputs.
+
+The control structures associated with SIE provide the Secure
+Instruction Data Area (SIDA), the Interception Parameters (IP) and the
+Secure Interception General Register Save Area. Guest GRs and most of
+the instruction data, such as I/O data structures, are filtered.
+Instruction data is copied to and from the SIDA when needed. Guest
+GRs are put into / retrieved from the Secure Interception General
+Register Save Area.
+
+Only GR values needed to emulate an instruction will be copied into this
+save area and the real register numbers will be hidden.
+
+The Interception Parameters state description field still contains
+the bytes of the instruction text, but with pre-set register values
+instead of the actual ones. I.e. each instruction always uses the same
+instruction text, in order not to leak guest instruction text.
+This also implies that the register content that a guest had in r<n>
+may be in r<m> from the hypervisor's point of view.
+
+The Secure Instruction Data Area contains instruction storage
+data. Instruction data, i.e. data being referenced by an instruction
+like the SCCB for sclp, is moved via the SIDA. When an instruction is
+intercepted, the SIE will only allow data and program interrupts for
+this instruction to be moved to the guest via the two data areas
+discussed before. Other data is either ignored or results in validity
+interceptions.
+
+
+Instruction emulation interceptions
+-----------------------------------
+There are two types of SIE secure instruction intercepts: the normal
+and the notification type. Normal secure instruction intercepts will
+make the guest pending for instruction completion of the intercepted
+instruction type, i.e. on SIE entry it is attempted to complete
+emulation of the instruction with the data provided by KVM. That might
+be a program exception or instruction completion.
+
+The notification type intercepts inform KVM about guest environment
+changes due to guest instruction interpretation. Such an interception
+is recognized, for example, for the store prefix instruction to provide
+the new lowcore location. On SIE reentry, any KVM data in the data areas
+is ignored and execution continues as if the guest instruction had
+completed. For that reason KVM is not allowed to inject a program
+interrupt.
+
+Links
+-----
+`KVM Forum 2019 presentation <https://static.sched.com/hosted_files/kvmforum2019/3b/ibm_protected_vms_s390x.pdf>`_