From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- arch/arm/lib/backtrace-clang.S | 230 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 230 insertions(+) create mode 100644 arch/arm/lib/backtrace-clang.S (limited to 'arch/arm/lib/backtrace-clang.S') diff --git a/arch/arm/lib/backtrace-clang.S b/arch/arm/lib/backtrace-clang.S new file mode 100644 index 000000000..290c52a60 --- /dev/null +++ b/arch/arm/lib/backtrace-clang.S @@ -0,0 +1,230 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * linux/arch/arm/lib/backtrace-clang.S + * + * Copyright (C) 2019 Nathan Huckleberry + * + */ +#include +#include +#include + .text + +/* fp is 0 or stack frame */ + +#define frame r4 +#define sv_fp r5 +#define sv_pc r6 +#define mask r7 +#define sv_lr r8 +#define loglvl r9 + +ENTRY(c_backtrace) + +#if !defined(CONFIG_FRAME_POINTER) || !defined(CONFIG_PRINTK) + ret lr +ENDPROC(c_backtrace) +#else + + +/* + * Clang does not store pc or sp in function prologues so we don't know exactly + * where the function starts. + * + * We can treat the current frame's lr as the saved pc and the preceding + * frame's lr as the current frame's lr, but we can't trace the most recent + * call. Inserting a false stack frame allows us to reference the function + * called last in the stacktrace. + * + * If the call instruction was a bl we can look at the callers branch + * instruction to calculate the saved pc. We can recover the pc in most cases, + * but in cases such as calling function pointers we cannot. In this case, + * default to using the lr. This will be some address in the function, but will + * not be the function start. + * + * Unfortunately due to the stack frame layout we can't dump r0 - r3, but these + * are less frequently saved. + * + * Stack frame layout: + * + * saved lr + * frame=> saved fp + * optionally saved caller registers (r4 - r10) + * optionally saved arguments (r0 - r3) + * + * + * + * Functions start with the following code sequence: + * corrected pc => stmfd sp!, {..., fp, lr} + * add fp, sp, #x + * stmfd sp!, {r0 - r3} (optional) + * + * + * + * + * + * + * The diagram below shows an example stack setup for dump_stack. + * + * The frame for c_backtrace has pointers to the code of dump_stack. This is + * why the frame of c_backtrace is used to for the pc calculation of + * dump_stack. This is why we must move back a frame to print dump_stack. + * + * The stored locals for dump_stack are in dump_stack's frame. This means that + * to fully print dump_stack's frame we need both the frame for dump_stack (for + * locals) and the frame that was called by dump_stack (for pc). + * + * To print locals we must know where the function start is. If we read the + * function prologue opcodes we can determine which variables are stored in the + * stack frame. + * + * To find the function start of dump_stack we can look at the stored LR of + * show_stack. It points at the instruction directly after the bl dump_stack. + * We can then read the offset from the bl opcode to determine where the branch + * takes us. The address calculated must be the start of dump_stack. + * + * c_backtrace frame dump_stack: + * {[LR] } ============| ... + * {[FP] } =======| | bl c_backtrace + * | |=> ... + * {[R4-R10]} | + * {[R0-R3] } | show_stack: + * dump_stack frame | ... + * {[LR] } =============| bl dump_stack + * {[FP] } <=======| |=> ... + * {[R4-R10]} + * {[R0-R3] } + */ + + stmfd sp!, {r4 - r9, fp, lr} @ Save an extra register + @ to ensure 8 byte alignment + movs frame, r0 @ if frame pointer is zero + beq no_frame @ we have no stack frames + mov loglvl, r2 + tst r1, #0x10 @ 26 or 32-bit mode? + moveq mask, #0xfc000003 + movne mask, #0 @ mask for 32-bit + +/* + * Switches the current frame to be the frame for dump_stack. + */ + add frame, sp, #24 @ switch to false frame +for_each_frame: tst frame, mask @ Check for address exceptions + bne no_frame + +/* + * sv_fp is the stack frame with the locals for the current considered + * function. + * + * sv_pc is the saved lr frame the frame above. This is a pointer to a code + * address within the current considered function, but it is not the function + * start. This value gets updated to be the function start later if it is + * possible. + */ +1001: ldr sv_pc, [frame, #4] @ get saved 'pc' +1002: ldr sv_fp, [frame, #0] @ get saved fp + + teq sv_fp, mask @ make sure next frame exists + beq no_frame + +/* + * sv_lr is the lr from the function that called the current function. This is + * a pointer to a code address in the current function's caller. sv_lr-4 is + * the instruction used to call the current function. + * + * This sv_lr can be used to calculate the function start if the function was + * called using a bl instruction. If the function start can be recovered sv_pc + * is overwritten with the function start. + * + * If the current function was called using a function pointer we cannot + * recover the function start and instead continue with sv_pc as an arbitrary + * value within the current function. If this is the case we cannot print + * registers for the current function, but the stacktrace is still printed + * properly. + */ +1003: ldr sv_lr, [sv_fp, #4] @ get saved lr from next frame + +1004: ldr r0, [sv_lr, #-4] @ get call instruction + ldr r3, .Lopcode+4 + and r2, r3, r0 @ is this a bl call + teq r2, r3 + bne finished_setup @ give up if it's not + and r0, #0xffffff @ get call offset 24-bit int + lsl r0, r0, #8 @ sign extend offset + asr r0, r0, #8 + ldr sv_pc, [sv_fp, #4] @ get lr address + add sv_pc, sv_pc, #-4 @ get call instruction address + add sv_pc, sv_pc, #8 @ take care of prefetch + add sv_pc, sv_pc, r0, lsl #2@ find function start + +finished_setup: + + bic sv_pc, sv_pc, mask @ mask PC/LR for the mode + +/* + * Print the function (sv_pc) and where it was called from (sv_lr). + */ + mov r0, sv_pc + + mov r1, sv_lr + mov r2, frame + bic r1, r1, mask @ mask PC/LR for the mode + mov r3, loglvl + bl dump_backtrace_entry + +/* + * Test if the function start is a stmfd instruction to determine which + * registers were stored in the function prologue. + * + * If we could not recover the sv_pc because we were called through a function + * pointer the comparison will fail and no registers will print. Unwinding will + * continue as if there had been no registers stored in this frame. + */ +1005: ldr r1, [sv_pc, #0] @ if stmfd sp!, {..., fp, lr} + ldr r3, .Lopcode @ instruction exists, + teq r3, r1, lsr #11 + ldr r0, [frame] @ locals are stored in + @ the preceding frame + subeq r0, r0, #4 + mov r2, loglvl + bleq dump_backtrace_stm @ dump saved registers + +/* + * If we are out of frames or if the next frame is invalid. + */ + teq sv_fp, #0 @ zero saved fp means + beq no_frame @ no further frames + + cmp sv_fp, frame @ next frame must be + mov frame, sv_fp @ above the current frame +#ifdef CONFIG_IRQSTACKS + @ + @ Kernel stacks may be discontiguous in memory. If the next + @ frame is below the previous frame, accept it as long as it + @ lives in kernel memory. + @ + cmpls sv_fp, #PAGE_OFFSET +#endif + bhi for_each_frame + +1006: adr r0, .Lbad + mov r1, loglvl + mov r2, frame + bl _printk +no_frame: ldmfd sp!, {r4 - r9, fp, pc} +ENDPROC(c_backtrace) + .pushsection __ex_table,"a" + .align 3 + .long 1001b, 1006b + .long 1002b, 1006b + .long 1003b, 1006b + .long 1004b, finished_setup + .long 1005b, 1006b + .popsection + +.Lbad: .asciz "%sBacktrace aborted due to bad frame pointer <%p>\n" + .align +.Lopcode: .word 0xe92d4800 >> 11 @ stmfd sp!, {... fp, lr} + .word 0x0b000000 @ bl if these bits are set + +#endif -- cgit v1.2.3