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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)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/arm64/kernel/entry-ftrace.S
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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(). ...
Diffstat (limited to 'arch/arm64/kernel/entry-ftrace.S')
-rw-r--r--arch/arm64/kernel/entry-ftrace.S292
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diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S
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@@ -0,0 +1,292 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * arch/arm64/kernel/entry-ftrace.S
+ *
+ * Copyright (C) 2013 Linaro Limited
+ * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
+ */
+
+#include <linux/linkage.h>
+#include <linux/cfi_types.h>
+#include <asm/asm-offsets.h>
+#include <asm/assembler.h>
+#include <asm/ftrace.h>
+#include <asm/insn.h>
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS
+/*
+ * Due to -fpatchable-function-entry=2, the compiler has placed two NOPs before
+ * the regular function prologue. For an enabled callsite, ftrace_init_nop() and
+ * ftrace_make_call() have patched those NOPs to:
+ *
+ * MOV X9, LR
+ * BL ftrace_caller
+ *
+ * Each instrumented function follows the AAPCS, so here x0-x8 and x18-x30 are
+ * live (x18 holds the Shadow Call Stack pointer), and x9-x17 are safe to
+ * clobber.
+ *
+ * We save the callsite's context into a struct ftrace_regs before invoking any
+ * ftrace callbacks. So that we can get a sensible backtrace, we create frame
+ * records for the callsite and the ftrace entry assembly. This is not
+ * sufficient for reliable stacktrace: until we create the callsite stack
+ * record, its caller is missing from the LR and existing chain of frame
+ * records.
+ */
+SYM_CODE_START(ftrace_caller)
+ bti c
+
+ /* Save original SP */
+ mov x10, sp
+
+ /* Make room for ftrace regs, plus two frame records */
+ sub sp, sp, #(FREGS_SIZE + 32)
+
+ /* Save function arguments */
+ stp x0, x1, [sp, #FREGS_X0]
+ stp x2, x3, [sp, #FREGS_X2]
+ stp x4, x5, [sp, #FREGS_X4]
+ stp x6, x7, [sp, #FREGS_X6]
+ str x8, [sp, #FREGS_X8]
+
+ /* Save the callsite's FP, LR, SP */
+ str x29, [sp, #FREGS_FP]
+ str x9, [sp, #FREGS_LR]
+ str x10, [sp, #FREGS_SP]
+
+ /* Save the PC after the ftrace callsite */
+ str x30, [sp, #FREGS_PC]
+
+ /* Create a frame record for the callsite above the ftrace regs */
+ stp x29, x9, [sp, #FREGS_SIZE + 16]
+ add x29, sp, #FREGS_SIZE + 16
+
+ /* Create our frame record above the ftrace regs */
+ stp x29, x30, [sp, #FREGS_SIZE]
+ add x29, sp, #FREGS_SIZE
+
+ /* Prepare arguments for the the tracer func */
+ sub x0, x30, #AARCH64_INSN_SIZE // ip (callsite's BL insn)
+ mov x1, x9 // parent_ip (callsite's LR)
+ mov x3, sp // regs
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS
+ /*
+ * The literal pointer to the ops is at an 8-byte aligned boundary
+ * which is either 12 or 16 bytes before the BL instruction in the call
+ * site. See ftrace_call_adjust() for details.
+ *
+ * Therefore here the LR points at `literal + 16` or `literal + 20`,
+ * and we can find the address of the literal in either case by
+ * aligning to an 8-byte boundary and subtracting 16. We do the
+ * alignment first as this allows us to fold the subtraction into the
+ * LDR.
+ */
+ bic x2, x30, 0x7
+ ldr x2, [x2, #-16] // op
+
+ ldr x4, [x2, #FTRACE_OPS_FUNC] // op->func
+ blr x4 // op->func(ip, parent_ip, op, regs)
+
+#else
+ ldr_l x2, function_trace_op // op
+
+SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL)
+ bl ftrace_stub // func(ip, parent_ip, op, regs)
+#endif
+
+/*
+ * At the callsite x0-x8 and x19-x30 were live. Any C code will have preserved
+ * x19-x29 per the AAPCS, and we created frame records upon entry, so we need
+ * to restore x0-x8, x29, and x30.
+ */
+ /* Restore function arguments */
+ ldp x0, x1, [sp, #FREGS_X0]
+ ldp x2, x3, [sp, #FREGS_X2]
+ ldp x4, x5, [sp, #FREGS_X4]
+ ldp x6, x7, [sp, #FREGS_X6]
+ ldr x8, [sp, #FREGS_X8]
+
+ /* Restore the callsite's FP, LR, PC */
+ ldr x29, [sp, #FREGS_FP]
+ ldr x30, [sp, #FREGS_LR]
+ ldr x9, [sp, #FREGS_PC]
+
+ /* Restore the callsite's SP */
+ add sp, sp, #FREGS_SIZE + 32
+
+ ret x9
+SYM_CODE_END(ftrace_caller)
+
+#else /* CONFIG_DYNAMIC_FTRACE_WITH_ARGS */
+
+/*
+ * Gcc with -pg will put the following code in the beginning of each function:
+ * mov x0, x30
+ * bl _mcount
+ * [function's body ...]
+ * "bl _mcount" may be replaced to "bl ftrace_caller" or NOP if dynamic
+ * ftrace is enabled.
+ *
+ * Please note that x0 as an argument will not be used here because we can
+ * get lr(x30) of instrumented function at any time by winding up call stack
+ * as long as the kernel is compiled without -fomit-frame-pointer.
+ * (or CONFIG_FRAME_POINTER, this is forced on arm64)
+ *
+ * stack layout after mcount_enter in _mcount():
+ *
+ * current sp/fp => 0:+-----+
+ * in _mcount() | x29 | -> instrumented function's fp
+ * +-----+
+ * | x30 | -> _mcount()'s lr (= instrumented function's pc)
+ * old sp => +16:+-----+
+ * when instrumented | |
+ * function calls | ... |
+ * _mcount() | |
+ * | |
+ * instrumented => +xx:+-----+
+ * function's fp | x29 | -> parent's fp
+ * +-----+
+ * | x30 | -> instrumented function's lr (= parent's pc)
+ * +-----+
+ * | ... |
+ */
+
+ .macro mcount_enter
+ stp x29, x30, [sp, #-16]!
+ mov x29, sp
+ .endm
+
+ .macro mcount_exit
+ ldp x29, x30, [sp], #16
+ ret
+ .endm
+
+ .macro mcount_adjust_addr rd, rn
+ sub \rd, \rn, #AARCH64_INSN_SIZE
+ .endm
+
+ /* for instrumented function's parent */
+ .macro mcount_get_parent_fp reg
+ ldr \reg, [x29]
+ ldr \reg, [\reg]
+ .endm
+
+ /* for instrumented function */
+ .macro mcount_get_pc0 reg
+ mcount_adjust_addr \reg, x30
+ .endm
+
+ .macro mcount_get_pc reg
+ ldr \reg, [x29, #8]
+ mcount_adjust_addr \reg, \reg
+ .endm
+
+ .macro mcount_get_lr reg
+ ldr \reg, [x29]
+ ldr \reg, [\reg, #8]
+ .endm
+
+ .macro mcount_get_lr_addr reg
+ ldr \reg, [x29]
+ add \reg, \reg, #8
+ .endm
+
+/*
+ * _mcount() is used to build the kernel with -pg option, but all the branch
+ * instructions to _mcount() are replaced to NOP initially at kernel start up,
+ * and later on, NOP to branch to ftrace_caller() when enabled or branch to
+ * NOP when disabled per-function base.
+ */
+SYM_FUNC_START(_mcount)
+ ret
+SYM_FUNC_END(_mcount)
+EXPORT_SYMBOL(_mcount)
+NOKPROBE(_mcount)
+
+/*
+ * void ftrace_caller(unsigned long return_address)
+ * @return_address: return address to instrumented function
+ *
+ * This function is a counterpart of _mcount() in 'static' ftrace, and
+ * makes calls to:
+ * - tracer function to probe instrumented function's entry,
+ * - ftrace_graph_caller to set up an exit hook
+ */
+SYM_FUNC_START(ftrace_caller)
+ mcount_enter
+
+ mcount_get_pc0 x0 // function's pc
+ mcount_get_lr x1 // function's lr
+
+SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) // tracer(pc, lr);
+ nop // This will be replaced with "bl xxx"
+ // where xxx can be any kind of tracer.
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL) // ftrace_graph_caller();
+ nop // If enabled, this will be replaced
+ // "b ftrace_graph_caller"
+#endif
+
+ mcount_exit
+SYM_FUNC_END(ftrace_caller)
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+/*
+ * void ftrace_graph_caller(void)
+ *
+ * Called from _mcount() or ftrace_caller() when function_graph tracer is
+ * selected.
+ * This function w/ prepare_ftrace_return() fakes link register's value on
+ * the call stack in order to intercept instrumented function's return path
+ * and run return_to_handler() later on its exit.
+ */
+SYM_FUNC_START(ftrace_graph_caller)
+ mcount_get_pc x0 // function's pc
+ mcount_get_lr_addr x1 // pointer to function's saved lr
+ mcount_get_parent_fp x2 // parent's fp
+ bl prepare_ftrace_return // prepare_ftrace_return(pc, &lr, fp)
+
+ mcount_exit
+SYM_FUNC_END(ftrace_graph_caller)
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+#endif /* CONFIG_DYNAMIC_FTRACE_WITH_ARGS */
+
+SYM_TYPED_FUNC_START(ftrace_stub)
+ ret
+SYM_FUNC_END(ftrace_stub)
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+SYM_TYPED_FUNC_START(ftrace_stub_graph)
+ ret
+SYM_FUNC_END(ftrace_stub_graph)
+
+/*
+ * void return_to_handler(void)
+ *
+ * Run ftrace_return_to_handler() before going back to parent.
+ * @fp is checked against the value passed by ftrace_graph_caller().
+ */
+SYM_CODE_START(return_to_handler)
+ /* save return value regs */
+ sub sp, sp, #64
+ stp x0, x1, [sp]
+ stp x2, x3, [sp, #16]
+ stp x4, x5, [sp, #32]
+ stp x6, x7, [sp, #48]
+
+ mov x0, x29 // parent's fp
+ bl ftrace_return_to_handler// addr = ftrace_return_to_hander(fp);
+ mov x30, x0 // restore the original return address
+
+ /* restore return value regs */
+ ldp x0, x1, [sp]
+ ldp x2, x3, [sp, #16]
+ ldp x4, x5, [sp, #32]
+ ldp x6, x7, [sp, #48]
+ add sp, sp, #64
+
+ ret
+SYM_CODE_END(return_to_handler)
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */